(function (global, factory) {
	typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
	typeof define === 'function' && define.amd ? define(factory) :
	(global.shuffle = factory());
}(this, (function () { 'use strict';

// Polyfill for creating CustomEvents on IE9/10/11

// code pulled from:
// https://github.com/d4tocchini/customevent-polyfill
// https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent#Polyfill

try {
    var ce = new window.CustomEvent('test');
    ce.preventDefault();
    if (ce.defaultPrevented !== true) {
        // IE has problems with .preventDefault() on custom events
        // http://stackoverflow.com/questions/23349191
        throw new Error('Could not prevent default');
    }
} catch(e) {
  var CustomEvent$1 = function(event, params) {
    var evt, origPrevent;
    params = params || {
      bubbles: false,
      cancelable: false,
      detail: undefined
    };

    evt = document.createEvent("CustomEvent");
    evt.initCustomEvent(event, params.bubbles, params.cancelable, params.detail);
    origPrevent = evt.preventDefault;
    evt.preventDefault = function () {
      origPrevent.call(this);
      try {
        Object.defineProperty(this, 'defaultPrevented', {
          get: function () {
            return true;
          }
        });
      } catch(e) {
        this.defaultPrevented = true;
      }
    };
    return evt;
  };

  CustomEvent$1.prototype = window.Event.prototype;
  window.CustomEvent = CustomEvent$1; // expose definition to window
}

var proto = Element.prototype;
var vendor = proto.matches
  || proto.matchesSelector
  || proto.webkitMatchesSelector
  || proto.mozMatchesSelector
  || proto.msMatchesSelector
  || proto.oMatchesSelector;

var index = match;

/**
 * Match `el` to `selector`.
 *
 * @param {Element} el
 * @param {String} selector
 * @return {Boolean}
 * @api public
 */

function match(el, selector) {
  if (vendor) return vendor.call(el, selector);
  var nodes = el.parentNode.querySelectorAll(selector);
  for (var i = 0; i < nodes.length; i++) {
    if (nodes[i] == el) return true;
  }
  return false;
}

var commonjsGlobal = typeof window !== 'undefined' ? window : typeof global !== 'undefined' ? global : typeof self !== 'undefined' ? self : {};





function createCommonjsModule(fn, module) {
	return module = { exports: {} }, fn(module, module.exports), module.exports;
}

var index$1 = createCommonjsModule(function (module) {
'use strict';

// there's 3 implementations written in increasing order of efficiency

// 1 - no Set type is defined
function uniqNoSet(arr) {
	var ret = [];

	for (var i = 0; i < arr.length; i++) {
		if (ret.indexOf(arr[i]) === -1) {
			ret.push(arr[i]);
		}
	}

	return ret;
}

// 2 - a simple Set type is defined
function uniqSet(arr) {
	var seen = new Set();
	return arr.filter(function (el) {
		if (!seen.has(el)) {
			seen.add(el);
			return true;
		}

		return false;
	});
}

// 3 - a standard Set type is defined and it has a forEach method
function uniqSetWithForEach(arr) {
	var ret = [];

	(new Set(arr)).forEach(function (el) {
		ret.push(el);
	});

	return ret;
}

// V8 currently has a broken implementation
// https://github.com/joyent/node/issues/8449
function doesForEachActuallyWork() {
	var ret = false;

	(new Set([true])).forEach(function (el) {
		ret = el;
	});

	return ret === true;
}

if ('Set' in commonjsGlobal) {
	if (typeof Set.prototype.forEach === 'function' && doesForEachActuallyWork()) {
		module.exports = uniqSetWithForEach;
	} else {
		module.exports = uniqSet;
	}
} else {
	module.exports = uniqNoSet;
}
});

var immutable = extend;

var hasOwnProperty = Object.prototype.hasOwnProperty;

function extend() {
    var target = {};

    for (var i = 0; i < arguments.length; i++) {
        var source = arguments[i];

        for (var key in source) {
            if (hasOwnProperty.call(source, key)) {
                target[key] = source[key];
            }
        }
    }

    return target
}

var index$2 = throttle;

/**
 * Returns a new function that, when invoked, invokes `func` at most once per `wait` milliseconds.
 *
 * @param {Function} func Function to wrap.
 * @param {Number} wait Number of milliseconds that must elapse between `func` invocations.
 * @return {Function} A new function that wraps the `func` function passed in.
 */

function throttle (func, wait) {
  var ctx, args, rtn, timeoutID; // caching
  var last = 0;

  return function throttled () {
    ctx = this;
    args = arguments;
    var delta = new Date() - last;
    if (!timeoutID)
      if (delta >= wait) call();
      else timeoutID = setTimeout(call, wait - delta);
    return rtn;
  };

  function call () {
    timeoutID = 0;
    last = +new Date();
    rtn = func.apply(ctx, args);
    ctx = null;
    args = null;
  }
}

var index$3 = function parallel(fns, context, callback) {
  if (!callback) {
    if (typeof context === 'function') {
      callback = context;
      context = null;
    } else {
      callback = noop;
    }
  }

  var pending = fns && fns.length;
  if (!pending) return callback(null, []);

  var finished = false;
  var results = new Array(pending);

  fns.forEach(context ? function (fn, i) {
    fn.call(context, maybeDone(i));
  } : function (fn, i) {
    fn(maybeDone(i));
  });

  function maybeDone(i) {
    return function (err, result) {
      if (finished) return;

      if (err) {
        callback(err, results);
        finished = true;
        return
      }

      results[i] = result;

      if (!--pending) callback(null, results);
    }
  }
};

function noop() {}

/**
 * Always returns a numeric value, given a value. Logic from jQuery's `isNumeric`.
 * @param {*} value Possibly numeric value.
 * @return {number} `value` or zero if `value` isn't numeric.
 */
function getNumber(value) {
  return parseFloat(value) || 0;
}

var classCallCheck = function (instance, Constructor) {
  if (!(instance instanceof Constructor)) {
    throw new TypeError("Cannot call a class as a function");
  }
};

var createClass = function () {
  function defineProperties(target, props) {
    for (var i = 0; i < props.length; i++) {
      var descriptor = props[i];
      descriptor.enumerable = descriptor.enumerable || false;
      descriptor.configurable = true;
      if ("value" in descriptor) descriptor.writable = true;
      Object.defineProperty(target, descriptor.key, descriptor);
    }
  }

  return function (Constructor, protoProps, staticProps) {
    if (protoProps) defineProperties(Constructor.prototype, protoProps);
    if (staticProps) defineProperties(Constructor, staticProps);
    return Constructor;
  };
}();

var Point = function () {

  /**
   * Represents a coordinate pair.
   * @param {number} [x=0] X.
   * @param {number} [y=0] Y.
   */
  function Point(x, y) {
    classCallCheck(this, Point);

    this.x = getNumber(x);
    this.y = getNumber(y);
  }

  /**
   * Whether two points are equal.
   * @param {Point} a Point A.
   * @param {Point} b Point B.
   * @return {boolean}
   */


  createClass(Point, null, [{
    key: 'equals',
    value: function equals(a, b) {
      return a.x === b.x && a.y === b.y;
    }
  }]);
  return Point;
}();

var Classes = {
  BASE: 'shuffle',
  SHUFFLE_ITEM: 'shuffle-item',
  VISIBLE: 'shuffle-item--visible',
  HIDDEN: 'shuffle-item--hidden'
};

var id$1 = 0;

var ShuffleItem = function () {
  function ShuffleItem(element) {
    classCallCheck(this, ShuffleItem);

    id$1 += 1;
    this.id = id$1;
    this.element = element;
    this.isVisible = true;
  }

  createClass(ShuffleItem, [{
    key: 'show',
    value: function show() {
      this.isVisible = true;
      this.element.classList.remove(Classes.HIDDEN);
      this.element.classList.add(Classes.VISIBLE);
    }
  }, {
    key: 'hide',
    value: function hide() {
      this.isVisible = false;
      this.element.classList.remove(Classes.VISIBLE);
      this.element.classList.add(Classes.HIDDEN);
    }
  }, {
    key: 'init',
    value: function init() {
      this.addClasses([Classes.SHUFFLE_ITEM, Classes.VISIBLE]);
      this.applyCss(ShuffleItem.Css.INITIAL);
      this.scale = ShuffleItem.Scale.VISIBLE;
      this.point = new Point();
    }
  }, {
    key: 'addClasses',
    value: function addClasses(classes) {
      var _this = this;

      classes.forEach(function (className) {
        _this.element.classList.add(className);
      });
    }
  }, {
    key: 'removeClasses',
    value: function removeClasses(classes) {
      var _this2 = this;

      classes.forEach(function (className) {
        _this2.element.classList.remove(className);
      });
    }
  }, {
    key: 'applyCss',
    value: function applyCss(obj) {
      var _this3 = this;

      Object.keys(obj).forEach(function (key) {
        _this3.element.style[key] = obj[key];
      });
    }
  }, {
    key: 'dispose',
    value: function dispose() {
      this.removeClasses([Classes.HIDDEN, Classes.VISIBLE, Classes.SHUFFLE_ITEM]);

      this.element.removeAttribute('style');
      this.element = null;
    }
  }]);
  return ShuffleItem;
}();

ShuffleItem.Css = {
  INITIAL: {
    position: 'absolute',
    top: 0,
    left: 0,
    visibility: 'visible',
    'will-change': 'transform'
  },
  VISIBLE: {
    before: {
      opacity: 1,
      visibility: 'visible'
    },
    after: {}
  },
  HIDDEN: {
    before: {
      opacity: 0
    },
    after: {
      visibility: 'hidden'
    }
  }
};

ShuffleItem.Scale = {
  VISIBLE: 1,
  HIDDEN: 0.001
};

var element = document.body || document.documentElement;
var e$1 = document.createElement('div');
e$1.style.cssText = 'width:10px;padding:2px;box-sizing:border-box;';
element.appendChild(e$1);

var width = window.getComputedStyle(e$1, null).width;
var ret = width === '10px';

element.removeChild(e$1);

/**
 * Retrieve the computed style for an element, parsed as a float.
 * @param {Element} element Element to get style for.
 * @param {string} style Style property.
 * @param {CSSStyleDeclaration} [styles] Optionally include clean styles to
 *     use instead of asking for them again.
 * @return {number} The parsed computed value or zero if that fails because IE
 *     will return 'auto' when the element doesn't have margins instead of
 *     the computed style.
 */
function getNumberStyle(element, style) {
  var styles = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : window.getComputedStyle(element, null);

  var value = getNumber(styles[style]);

  // Support IE<=11 and W3C spec.
  if (!ret && style === 'width') {
    value += getNumber(styles.paddingLeft) + getNumber(styles.paddingRight) + getNumber(styles.borderLeftWidth) + getNumber(styles.borderRightWidth);
  } else if (!ret && style === 'height') {
    value += getNumber(styles.paddingTop) + getNumber(styles.paddingBottom) + getNumber(styles.borderTopWidth) + getNumber(styles.borderBottomWidth);
  }

  return value;
}

/**
 * Fisher-Yates shuffle.
 * http://stackoverflow.com/a/962890/373422
 * https://bost.ocks.org/mike/shuffle/
 * @param {Array} array Array to shuffle.
 * @return {Array} Randomly sorted array.
 */
function randomize(array) {
  var n = array.length;

  while (n) {
    n -= 1;
    var i = Math.floor(Math.random() * (n + 1));
    var temp = array[i];
    array[i] = array[n];
    array[n] = temp;
  }

  return array;
}

var defaults$1 = {
  // Use array.reverse() to reverse the results
  reverse: false,

  // Sorting function
  by: null,

  // If true, this will skip the sorting and return a randomized order in the array
  randomize: false,

  // Determines which property of each item in the array is passed to the
  // sorting method.
  key: 'element'
};

// You can return `undefined` from the `by` function to revert to DOM order.
function sorter(arr, options) {
  var opts = immutable(defaults$1, options);
  var original = [].slice.call(arr);
  var revert = false;

  if (!arr.length) {
    return [];
  }

  if (opts.randomize) {
    return randomize(arr);
  }

  // Sort the elements by the opts.by function.
  // If we don't have opts.by, default to DOM order
  if (typeof opts.by === 'function') {
    arr.sort(function (a, b) {
      // Exit early if we already know we want to revert
      if (revert) {
        return 0;
      }

      var valA = opts.by(a[opts.key]);
      var valB = opts.by(b[opts.key]);

      // If both values are undefined, use the DOM order
      if (valA === undefined && valB === undefined) {
        revert = true;
        return 0;
      }

      if (valA < valB || valA === 'sortFirst' || valB === 'sortLast') {
        return -1;
      }

      if (valA > valB || valA === 'sortLast' || valB === 'sortFirst') {
        return 1;
      }

      return 0;
    });
  }

  // Revert to the original array if necessary
  if (revert) {
    return original;
  }

  if (opts.reverse) {
    arr.reverse();
  }

  return arr;
}

var transitions = {};
var eventName = 'transitionend';
var count = 0;

function uniqueId() {
  count += 1;
  return eventName + count;
}

function cancelTransitionEnd(id) {
  if (transitions[id]) {
    transitions[id].element.removeEventListener(eventName, transitions[id].listener);
    transitions[id] = null;
    return true;
  }

  return false;
}

function onTransitionEnd(element, callback) {
  var id = uniqueId();
  var listener = function listener(evt) {
    if (evt.currentTarget === evt.target) {
      cancelTransitionEnd(id);
      callback(evt);
    }
  };

  element.addEventListener(eventName, listener);

  transitions[id] = { element: element, listener: listener };

  return id;
}

function arrayMax(array) {
  return Math.max.apply(Math, array); // eslint-disable-line prefer-spread
}

function arrayMin(array) {
  return Math.min.apply(Math, array); // eslint-disable-line prefer-spread
}

/**
 * Determine the number of columns an items spans.
 * @param {number} itemWidth Width of the item.
 * @param {number} columnWidth Width of the column (includes gutter).
 * @param {number} columns Total number of columns
 * @param {number} threshold A buffer value for the size of the column to fit.
 * @return {number}
 */
function getColumnSpan(itemWidth, columnWidth, columns, threshold) {
  var columnSpan = itemWidth / columnWidth;

  // If the difference between the rounded column span number and the
  // calculated column span number is really small, round the number to
  // make it fit.
  if (Math.abs(Math.round(columnSpan) - columnSpan) < threshold) {
    // e.g. columnSpan = 4.0089945390298745
    columnSpan = Math.round(columnSpan);
  }

  // Ensure the column span is not more than the amount of columns in the whole layout.
  return Math.min(Math.ceil(columnSpan), columns);
}

/**
 * Retrieves the column set to use for placement.
 * @param {number} columnSpan The number of columns this current item spans.
 * @param {number} columns The total columns in the grid.
 * @return {Array.<number>} An array of numbers represeting the column set.
 */
function getAvailablePositions(positions, columnSpan, columns) {
  // The item spans only one column.
  if (columnSpan === 1) {
    return positions;
  }

  // The item spans more than one column, figure out how many different
  // places it could fit horizontally.
  // The group count is the number of places within the positions this block
  // could fit, ignoring the current positions of items.
  // Imagine a 2 column brick as the second item in a 4 column grid with
  // 10px height each. Find the places it would fit:
  // [20, 10, 10, 0]
  //  |   |   |
  //  *   *   *
  //
  // Then take the places which fit and get the bigger of the two:
  // max([20, 10]), max([10, 10]), max([10, 0]) = [20, 10, 0]
  //
  // Next, find the first smallest number (the short column).
  // [20, 10, 0]
  //          |
  //          *
  //
  // And that's where it should be placed!
  //
  // Another example where the second column's item extends past the first:
  // [10, 20, 10, 0] => [20, 20, 10] => 10
  var available = [];

  // For how many possible positions for this item there are.
  for (var i = 0; i <= columns - columnSpan; i++) {
    // Find the bigger value for each place it could fit.
    available.push(arrayMax(positions.slice(i, i + columnSpan)));
  }

  return available;
}

/**
 * Find index of short column, the first from the left where this item will go.
 *
 * @param {Array.<number>} positions The array to search for the smallest number.
 * @param {number} buffer Optional buffer which is very useful when the height
 *     is a percentage of the width.
 * @return {number} Index of the short column.
 */
function getShortColumn(positions, buffer) {
  var minPosition = arrayMin(positions);
  for (var i = 0, len = positions.length; i < len; i++) {
    if (positions[i] >= minPosition - buffer && positions[i] <= minPosition + buffer) {
      return i;
    }
  }

  return 0;
}

/**
 * Determine the location of the next item, based on its size.
 * @param {Object} itemSize Object with width and height.
 * @param {Array.<number>} positions Positions of the other current items.
 * @param {number} gridSize The column width or row height.
 * @param {number} total The total number of columns or rows.
 * @param {number} threshold Buffer value for the column to fit.
 * @param {number} buffer Vertical buffer for the height of items.
 * @return {Point}
 */
function getItemPosition(_ref) {
  var itemSize = _ref.itemSize,
      positions = _ref.positions,
      gridSize = _ref.gridSize,
      total = _ref.total,
      threshold = _ref.threshold,
      buffer = _ref.buffer;

  var span = getColumnSpan(itemSize.width, gridSize, total, threshold);
  var setY = getAvailablePositions(positions, span, total);
  var shortColumnIndex = getShortColumn(setY, buffer);

  // Position the item
  var point = new Point(Math.round(gridSize * shortColumnIndex), Math.round(setY[shortColumnIndex]));

  // Update the columns array with the new values for each column.
  // e.g. before the update the columns could be [250, 0, 0, 0] for an item
  // which spans 2 columns. After it would be [250, itemHeight, itemHeight, 0].
  var setHeight = setY[shortColumnIndex] + itemSize.height;
  for (var i = 0; i < span; i++) {
    positions[shortColumnIndex + i] = setHeight;
  }

  return point;
}

function toArray$$1(arrayLike) {
  return Array.prototype.slice.call(arrayLike);
}

function arrayIncludes(array, obj) {
  return array.indexOf(obj) > -1;
}

// Used for unique instance variables
var id = 0;

var Shuffle = function () {

  /**
   * Categorize, sort, and filter a responsive grid of items.
   *
   * @param {Element} element An element which is the parent container for the grid items.
   * @param {Object} [options=Shuffle.options] Options object.
   * @constructor
   */
  function Shuffle(element) {
    var options = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
    classCallCheck(this, Shuffle);

    this.options = immutable(Shuffle.options, options);

    this.useSizer = false;
    this.lastSort = {};
    this.group = Shuffle.ALL_ITEMS;
    this.lastFilter = Shuffle.ALL_ITEMS;
    this.isEnabled = true;
    this.isDestroyed = false;
    this.isInitialized = false;
    this._transitions = [];
    this.isTransitioning = false;
    this._queue = [];

    var el = this._getElementOption(element);

    if (!el) {
      throw new TypeError('Shuffle needs to be initialized with an element.');
    }

    this.element = el;
    this.id = 'shuffle_' + id;
    id += 1;

    this._init();
    this.isInitialized = true;
  }

  createClass(Shuffle, [{
    key: '_init',
    value: function _init() {
      this.items = this._getItems();

      this.options.sizer = this._getElementOption(this.options.sizer);

      if (this.options.sizer) {
        this.useSizer = true;
      }

      // Add class and invalidate styles
      this.element.classList.add(Shuffle.Classes.BASE);

      // Set initial css for each item
      this._initItems();

      // Bind resize events
      this._onResize = this._getResizeFunction();
      window.addEventListener('resize', this._onResize);

      // Get container css all in one request. Causes reflow
      var containerCss = window.getComputedStyle(this.element, null);
      var containerWidth = Shuffle.getSize(this.element).width;

      // Add styles to the container if it doesn't have them.
      this._validateStyles(containerCss);

      // We already got the container's width above, no need to cause another
      // reflow getting it again... Calculate the number of columns there will be
      this._setColumns(containerWidth);

      // Kick off!
      this.filter(this.options.group, this.options.initialSort);

      // The shuffle items haven't had transitions set on them yet so the user
      // doesn't see the first layout. Set them now that the first layout is done.
      // First, however, a synchronous layout must be caused for the previous
      // styles to be applied without transitions.
      this.element.offsetWidth; // eslint-disable-line no-unused-expressions
      this._setTransitions();
      this.element.style.transition = 'height ' + this.options.speed + 'ms ' + this.options.easing;
    }

    /**
     * Returns a throttled and proxied function for the resize handler.
     * @return {Function}
     * @private
     */

  }, {
    key: '_getResizeFunction',
    value: function _getResizeFunction() {
      var resizeFunction = this._handleResize.bind(this);
      return this.options.throttle ? this.options.throttle(resizeFunction, this.options.throttleTime) : resizeFunction;
    }

    /**
     * Retrieve an element from an option.
     * @param {string|jQuery|Element} option The option to check.
     * @return {?Element} The plain element or null.
     * @private
     */

  }, {
    key: '_getElementOption',
    value: function _getElementOption(option) {
      // If column width is a string, treat is as a selector and search for the
      // sizer element within the outermost container
      if (typeof option === 'string') {
        return this.element.querySelector(option);

        // Check for an element
      } else if (option && option.nodeType && option.nodeType === 1) {
        return option;

        // Check for jQuery object
      } else if (option && option.jquery) {
        return option[0];
      }

      return null;
    }

    /**
     * Ensures the shuffle container has the css styles it needs applied to it.
     * @param {Object} styles Key value pairs for position and overflow.
     * @private
     */

  }, {
    key: '_validateStyles',
    value: function _validateStyles(styles) {
      // Position cannot be static.
      if (styles.position === 'static') {
        this.element.style.position = 'relative';
      }

      // Overflow has to be hidden.
      if (styles.overflow !== 'hidden') {
        this.element.style.overflow = 'hidden';
      }
    }

    /**
     * Filter the elements by a category.
     * @param {string} [category] Category to filter by. If it's given, the last
     *     category will be used to filter the items.
     * @param {Array} [collection] Optionally filter a collection. Defaults to
     *     all the items.
     * @return {!{visible: Array, hidden: Array}}
     * @private
     */

  }, {
    key: '_filter',
    value: function _filter() {
      var category = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : this.lastFilter;
      var collection = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : this.items;

      var set$$1 = this._getFilteredSets(category, collection);

      // Individually add/remove hidden/visible classes
      this._toggleFilterClasses(set$$1);

      // Save the last filter in case elements are appended.
      this.lastFilter = category;

      // This is saved mainly because providing a filter function (like searching)
      // will overwrite the `lastFilter` property every time its called.
      if (typeof category === 'string') {
        this.group = category;
      }

      return set$$1;
    }

    /**
     * Returns an object containing the visible and hidden elements.
     * @param {string|Function} category Category or function to filter by.
     * @param {Array.<Element>} items A collection of items to filter.
     * @return {!{visible: Array, hidden: Array}}
     * @private
     */

  }, {
    key: '_getFilteredSets',
    value: function _getFilteredSets(category, items) {
      var _this = this;

      var visible = [];
      var hidden = [];

      // category === 'all', add visible class to everything
      if (category === Shuffle.ALL_ITEMS) {
        visible = items;

        // Loop through each item and use provided function to determine
        // whether to hide it or not.
      } else {
        items.forEach(function (item) {
          if (_this._doesPassFilter(category, item.element)) {
            visible.push(item);
          } else {
            hidden.push(item);
          }
        });
      }

      return {
        visible: visible,
        hidden: hidden
      };
    }

    /**
     * Test an item to see if it passes a category.
     * @param {string|Function} category Category or function to filter by.
     * @param {Element} element An element to test.
     * @return {boolean} Whether it passes the category/filter.
     * @private
     */

  }, {
    key: '_doesPassFilter',
    value: function _doesPassFilter(category, element) {
      if (typeof category === 'function') {
        return category.call(element, element, this);
      }

      // Check each element's data-groups attribute against the given category.
      var attr = element.getAttribute('data-' + Shuffle.FILTER_ATTRIBUTE_KEY);
      var keys = this.options.delimeter ? attr.split(this.options.delimeter) : JSON.parse(attr);

      function testCategory(category) {
        return arrayIncludes(keys, category);
      }

      if (Array.isArray(category)) {
        if (this.options.filterMode === Shuffle.FilterMode.ANY) {
          return category.some(testCategory);
        }
        return category.every(testCategory);
      }

      return arrayIncludes(keys, category);
    }

    /**
     * Toggles the visible and hidden class names.
     * @param {{visible, hidden}} Object with visible and hidden arrays.
     * @private
     */

  }, {
    key: '_toggleFilterClasses',
    value: function _toggleFilterClasses(_ref) {
      var visible = _ref.visible,
          hidden = _ref.hidden;

      visible.forEach(function (item) {
        item.show();
      });

      hidden.forEach(function (item) {
        item.hide();
      });
    }

    /**
     * Set the initial css for each item
     * @param {Array.<ShuffleItem>} [items] Optionally specifiy at set to initialize.
     * @private
     */

  }, {
    key: '_initItems',
    value: function _initItems() {
      var items = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : this.items;

      items.forEach(function (item) {
        item.init();
      });
    }

    /**
     * Remove element reference and styles.
     * @private
     */

  }, {
    key: '_disposeItems',
    value: function _disposeItems() {
      var items = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : this.items;

      items.forEach(function (item) {
        item.dispose();
      });
    }

    /**
     * Updates the visible item count.
     * @private
     */

  }, {
    key: '_updateItemCount',
    value: function _updateItemCount() {
      this.visibleItems = this._getFilteredItems().length;
    }

    /**
     * Sets css transform transition on a group of elements. This is not executed
     * at the same time as `item.init` so that transitions don't occur upon
     * initialization of Shuffle.
     * @param {Array.<ShuffleItem>} items Shuffle items to set transitions on.
     * @private
     */

  }, {
    key: '_setTransitions',
    value: function _setTransitions() {
      var items = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : this.items;

      var speed = this.options.speed;
      var easing = this.options.easing;

      var str = this.options.useTransforms ? 'transform ' + speed + 'ms ' + easing + ', opacity ' + speed + 'ms ' + easing : 'top ' + speed + 'ms ' + easing + ', left ' + speed + 'ms ' + easing + ', opacity ' + speed + 'ms ' + easing;

      items.forEach(function (item) {
        item.element.style.transition = str;
      });
    }
  }, {
    key: '_getItems',
    value: function _getItems() {
      var _this2 = this;

      return toArray$$1(this.element.children).filter(function (el) {
        return index(el, _this2.options.itemSelector);
      }).map(function (el) {
        return new ShuffleItem(el);
      });
    }

    /**
     * When new elements are added to the shuffle container, update the array of
     * items because that is the order `_layout` calls them.
     */

  }, {
    key: '_updateItemsOrder',
    value: function _updateItemsOrder() {
      var children = this.element.children;
      this.items = sorter(this.items, {
        by: function by(element) {
          return Array.prototype.indexOf.call(children, element);
        }
      });
    }
  }, {
    key: '_getFilteredItems',
    value: function _getFilteredItems() {
      return this.items.filter(function (item) {
        return item.isVisible;
      });
    }
  }, {
    key: '_getConcealedItems',
    value: function _getConcealedItems() {
      return this.items.filter(function (item) {
        return !item.isVisible;
      });
    }

    /**
     * Returns the column size, based on column width and sizer options.
     * @param {number} containerWidth Size of the parent container.
     * @param {number} gutterSize Size of the gutters.
     * @return {number}
     * @private
     */

  }, {
    key: '_getColumnSize',
    value: function _getColumnSize(containerWidth, gutterSize) {
      var size = void 0;

      // If the columnWidth property is a function, then the grid is fluid
      if (typeof this.options.columnWidth === 'function') {
        size = this.options.columnWidth(containerWidth);

        // columnWidth option isn't a function, are they using a sizing element?
      } else if (this.useSizer) {
        size = Shuffle.getSize(this.options.sizer).width;

        // if not, how about the explicitly set option?
      } else if (this.options.columnWidth) {
        size = this.options.columnWidth;

        // or use the size of the first item
      } else if (this.items.length > 0) {
        size = Shuffle.getSize(this.items[0].element, true).width;

        // if there's no items, use size of container
      } else {
        size = containerWidth;
      }

      // Don't let them set a column width of zero.
      if (size === 0) {
        size = containerWidth;
      }

      return size + gutterSize;
    }

    /**
     * Returns the gutter size, based on gutter width and sizer options.
     * @param {number} containerWidth Size of the parent container.
     * @return {number}
     * @private
     */

  }, {
    key: '_getGutterSize',
    value: function _getGutterSize(containerWidth) {
      var size = void 0;
      if (typeof this.options.gutterWidth === 'function') {
        size = this.options.gutterWidth(containerWidth);
      } else if (this.useSizer) {
        size = getNumberStyle(this.options.sizer, 'marginLeft');
      } else {
        size = this.options.gutterWidth;
      }

      return size;
    }

    /**
     * Calculate the number of columns to be used. Gets css if using sizer element.
     * @param {number} [containerWidth] Optionally specify a container width if
     *    it's already available.
     */

  }, {
    key: '_setColumns',
    value: function _setColumns() {
      var containerWidth = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : Shuffle.getSize(this.element).width;

      var gutter = this._getGutterSize(containerWidth);
      var columnWidth = this._getColumnSize(containerWidth, gutter);
      var calculatedColumns = (containerWidth + gutter) / columnWidth;

      // Widths given from getStyles are not precise enough...
      if (Math.abs(Math.round(calculatedColumns) - calculatedColumns) < this.options.columnThreshold) {
        // e.g. calculatedColumns = 11.998876
        calculatedColumns = Math.round(calculatedColumns);
      }

      this.cols = Math.max(Math.floor(calculatedColumns), 1);
      this.containerWidth = containerWidth;
      this.colWidth = columnWidth;
    }

    /**
     * Adjust the height of the grid
     */

  }, {
    key: '_setContainerSize',
    value: function _setContainerSize() {
      this.element.style.height = this._getContainerSize() + 'px';
    }

    /**
     * Based on the column heights, it returns the biggest one.
     * @return {number}
     * @private
     */

  }, {
    key: '_getContainerSize',
    value: function _getContainerSize() {
      return arrayMax(this.positions);
    }

    /**
     * Get the clamped stagger amount.
     * @param {number} index Index of the item to be staggered.
     * @return {number}
     */

  }, {
    key: '_getStaggerAmount',
    value: function _getStaggerAmount(index$$1) {
      return Math.min(index$$1 * this.options.staggerAmount, this.options.staggerAmountMax);
    }

    /**
     * @return {boolean} Whether the event was prevented or not.
     */

  }, {
    key: '_dispatch',
    value: function _dispatch(name) {
      var details = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};

      if (this.isDestroyed) {
        return false;
      }

      details.shuffle = this;
      return !this.element.dispatchEvent(new CustomEvent(name, {
        bubbles: true,
        cancelable: false,
        detail: details
      }));
    }

    /**
     * Zeros out the y columns array, which is used to determine item placement.
     * @private
     */

  }, {
    key: '_resetCols',
    value: function _resetCols() {
      var i = this.cols;
      this.positions = [];
      while (i) {
        i -= 1;
        this.positions.push(0);
      }
    }

    /**
     * Loops through each item that should be shown and calculates the x, y position.
     * @param {Array.<ShuffleItem>} items Array of items that will be shown/layed
     *     out in order in their array.
     */

  }, {
    key: '_layout',
    value: function _layout(items) {
      var _this3 = this;

      var count = 0;
      items.forEach(function (item) {
        var currPos = item.point;
        var currScale = item.scale;
        var itemSize = Shuffle.getSize(item.element, true);
        var pos = _this3._getItemPosition(itemSize);

        function callback() {
          item.element.style.transitionDelay = '';
          item.applyCss(ShuffleItem.Css.VISIBLE.after);
        }

        // If the item will not change its position, do not add it to the render
        // queue. Transitions don't fire when setting a property to the same value.
        if (Point.equals(currPos, pos) && currScale === ShuffleItem.Scale.VISIBLE) {
          item.applyCss(ShuffleItem.Css.VISIBLE.before);
          callback();
          return;
        }

        item.point = pos;
        item.scale = ShuffleItem.Scale.VISIBLE;

        // Use xtend here to clone the object so that the `before` object isn't
        // modified when the transition delay is added.
        var styles = immutable(ShuffleItem.Css.VISIBLE.before);
        styles.transitionDelay = _this3._getStaggerAmount(count) + 'ms';

        _this3._queue.push({
          item: item,
          styles: styles,
          callback: callback
        });

        count += 1;
      });
    }

    /**
     * Determine the location of the next item, based on its size.
     * @param {{width: number, height: number}} itemSize Object with width and height.
     * @return {Point}
     * @private
     */

  }, {
    key: '_getItemPosition',
    value: function _getItemPosition(itemSize) {
      return getItemPosition({
        itemSize: itemSize,
        positions: this.positions,
        gridSize: this.colWidth,
        total: this.cols,
        threshold: this.options.columnThreshold,
        buffer: this.options.buffer
      });
    }

    /**
     * Hides the elements that don't match our filter.
     * @param {Array.<ShuffleItem>} collection Collection to shrink.
     * @private
     */

  }, {
    key: '_shrink',
    value: function _shrink() {
      var _this4 = this;

      var collection = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : this._getConcealedItems();

      var count = 0;
      collection.forEach(function (item) {
        function callback() {
          item.applyCss(ShuffleItem.Css.HIDDEN.after);
        }

        // Continuing would add a transitionend event listener to the element, but
        // that listener would not execute because the transform and opacity would
        // stay the same.
        // The callback is executed here because it is not guaranteed to be called
        // after the transitionend event because the transitionend could be
        // canceled if another animation starts.
        if (item.scale === ShuffleItem.Scale.HIDDEN) {
          item.applyCss(ShuffleItem.Css.HIDDEN.before);
          callback();
          return;
        }

        item.scale = ShuffleItem.Scale.HIDDEN;

        var styles = immutable(ShuffleItem.Css.HIDDEN.before);
        styles.transitionDelay = _this4._getStaggerAmount(count) + 'ms';

        _this4._queue.push({
          item: item,
          styles: styles,
          callback: callback
        });

        count += 1;
      });
    }

    /**
     * Resize handler.
     * @private
     */

  }, {
    key: '_handleResize',
    value: function _handleResize() {
      // If shuffle is disabled, destroyed, don't do anything
      if (!this.isEnabled || this.isDestroyed) {
        return;
      }

      // Will need to check height in the future if it's layed out horizontaly
      var containerWidth = Shuffle.getSize(this.element).width;

      // containerWidth hasn't changed, don't do anything
      if (containerWidth === this.containerWidth) {
        return;
      }

      this.update();
    }

    /**
     * Returns styles which will be applied to the an item for a transition.
     * @param {Object} obj Transition options.
     * @return {!Object} Transforms for transitions, left/top for animate.
     * @private
     */

  }, {
    key: '_getStylesForTransition',
    value: function _getStylesForTransition(_ref2) {
      var item = _ref2.item,
          styles = _ref2.styles;

      if (!styles.transitionDelay) {
        styles.transitionDelay = '0ms';
      }

      var x = item.point.x;
      var y = item.point.y;

      if (this.options.useTransforms) {
        styles.transform = 'translate(' + x + 'px, ' + y + 'px) scale(' + item.scale + ')';
      } else {
        styles.left = x + 'px';
        styles.top = y + 'px';
      }

      return styles;
    }

    /**
     * Listen for the transition end on an element and execute the itemCallback
     * when it finishes.
     * @param {Element} element Element to listen on.
     * @param {Function} itemCallback Callback for the item.
     * @param {Function} done Callback to notify `parallel` that this one is done.
     */

  }, {
    key: '_whenTransitionDone',
    value: function _whenTransitionDone(element, itemCallback, done) {
      var id = onTransitionEnd(element, function (evt) {
        itemCallback();
        done(null, evt);
      });

      this._transitions.push(id);
    }

    /**
     * Return a function which will set CSS styles and call the `done` function
     * when (if) the transition finishes.
     * @param {Object} opts Transition object.
     * @return {Function} A function to be called with a `done` function.
     */

  }, {
    key: '_getTransitionFunction',
    value: function _getTransitionFunction(opts) {
      var _this5 = this;

      return function (done) {
        opts.item.applyCss(_this5._getStylesForTransition(opts));
        _this5._whenTransitionDone(opts.item.element, opts.callback, done);
      };
    }

    /**
     * Execute the styles gathered in the style queue. This applies styles to elements,
     * triggering transitions.
     * @private
     */

  }, {
    key: '_processQueue',
    value: function _processQueue() {
      if (this.isTransitioning) {
        this._cancelMovement();
      }

      var hasSpeed = this.options.speed > 0;
      var hasQueue = this._queue.length > 0;

      if (hasQueue && hasSpeed && this.isInitialized) {
        this._startTransitions(this._queue);
      } else if (hasQueue) {
        this._styleImmediately(this._queue);
        this._dispatchLayout();

        // A call to layout happened, but none of the newly visible items will
        // change position or the transition duration is zero, which will not trigger
        // the transitionend event.
      } else {
        this._dispatchLayout();
      }

      // Remove everything in the style queue
      this._queue.length = 0;
    }

    /**
     * Wait for each transition to finish, the emit the layout event.
     * @param {Array.<Object>} transitions Array of transition objects.
     */

  }, {
    key: '_startTransitions',
    value: function _startTransitions(transitions) {
      var _this6 = this;

      // Set flag that shuffle is currently in motion.
      this.isTransitioning = true;

      // Create an array of functions to be called.
      var callbacks = transitions.map(function (obj) {
        return _this6._getTransitionFunction(obj);
      });

      index$3(callbacks, this._movementFinished.bind(this));
    }
  }, {
    key: '_cancelMovement',
    value: function _cancelMovement() {
      // Remove the transition end event for each listener.
      this._transitions.forEach(cancelTransitionEnd);

      // Reset the array.
      this._transitions.length = 0;

      // Show it's no longer active.
      this.isTransitioning = false;
    }

    /**
     * Apply styles without a transition.
     * @param {Array.<Object>} objects Array of transition objects.
     * @private
     */

  }, {
    key: '_styleImmediately',
    value: function _styleImmediately(objects) {
      var _this7 = this;

      if (objects.length) {
        var elements = objects.map(function (obj) {
          return obj.item.element;
        });

        Shuffle._skipTransitions(elements, function () {
          objects.forEach(function (obj) {
            obj.item.applyCss(_this7._getStylesForTransition(obj));
            obj.callback();
          });
        });
      }
    }
  }, {
    key: '_movementFinished',
    value: function _movementFinished() {
      this._transitions.length = 0;
      this.isTransitioning = false;
      this._dispatchLayout();
    }
  }, {
    key: '_dispatchLayout',
    value: function _dispatchLayout() {
      this._dispatch(Shuffle.EventType.LAYOUT);
    }

    /**
     * The magic. This is what makes the plugin 'shuffle'
     * @param {string|Function|Array.<string>} [category] Category to filter by.
     *     Can be a function, string, or array of strings.
     * @param {Object} [sortObj] A sort object which can sort the visible set
     */

  }, {
    key: 'filter',
    value: function filter(category, sortObj) {
      if (!this.isEnabled) {
        return;
      }

      if (!category || category && category.length === 0) {
        category = Shuffle.ALL_ITEMS; // eslint-disable-line no-param-reassign
      }

      this._filter(category);

      // Shrink each hidden item
      this._shrink();

      // How many visible elements?
      this._updateItemCount();

      // Update transforms on visible elements so they will animate to their new positions.
      this.sort(sortObj);
    }

    /**
     * Gets the visible elements, sorts them, and passes them to layout.
     * @param {Object} opts the options object for the sorted plugin
     */

  }, {
    key: 'sort',
    value: function sort() {
      var opts = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : this.lastSort;

      if (!this.isEnabled) {
        return;
      }

      this._resetCols();

      var items = this._getFilteredItems();
      items = sorter(items, opts);

      this._layout(items);

      // `_layout` always happens after `_shrink`, so it's safe to process the style
      // queue here with styles from the shrink method.
      this._processQueue();

      // Adjust the height of the container.
      this._setContainerSize();

      this.lastSort = opts;
    }

    /**
     * Reposition everything.
     * @param {boolean} isOnlyLayout If true, column and gutter widths won't be
     *     recalculated.
     */

  }, {
    key: 'update',
    value: function update(isOnlyLayout) {
      if (this.isEnabled) {
        if (!isOnlyLayout) {
          // Get updated colCount
          this._setColumns();
        }

        // Layout items
        this.sort();
      }
    }

    /**
     * Use this instead of `update()` if you don't need the columns and gutters updated
     * Maybe an image inside `shuffle` loaded (and now has a height), which means calculations
     * could be off.
     */

  }, {
    key: 'layout',
    value: function layout() {
      this.update(true);
    }

    /**
     * New items have been appended to shuffle. Mix them in with the current
     * filter or sort status.
     * @param {Array.<Element>} newItems Collection of new items.
     */

  }, {
    key: 'add',
    value: function add(newItems) {
      var items = index$1(newItems).map(function (el) {
        return new ShuffleItem(el);
      });

      // Add classes and set initial positions.
      this._initItems(items);

      // Add transition to each item.
      this._setTransitions(items);

      // Update the list of items.
      this.items = this.items.concat(items);
      this._updateItemsOrder();
      this.filter(this.lastFilter);
    }

    /**
     * Disables shuffle from updating dimensions and layout on resize
     */

  }, {
    key: 'disable',
    value: function disable() {
      this.isEnabled = false;
    }

    /**
     * Enables shuffle again
     * @param {boolean} [isUpdateLayout=true] if undefined, shuffle will update columns and gutters
     */

  }, {
    key: 'enable',
    value: function enable(isUpdateLayout) {
      this.isEnabled = true;
      if (isUpdateLayout !== false) {
        this.update();
      }
    }

    /**
     * Remove 1 or more shuffle items
     * @param {Array.<Element>} elements An array containing one or more
     *     elements in shuffle
     * @return {Shuffle} The shuffle object
     */

  }, {
    key: 'remove',
    value: function remove(elements) {
      var _this8 = this;

      if (!elements.length) {
        return;
      }

      var collection = index$1(elements);

      var oldItems = collection.map(function (element) {
        return _this8.getItemByElement(element);
      }).filter(function (item) {
        return !!item;
      });

      var handleLayout = function handleLayout() {
        _this8.element.removeEventListener(Shuffle.EventType.LAYOUT, handleLayout);
        _this8._disposeItems(oldItems);

        // Remove the collection in the callback
        collection.forEach(function (element) {
          element.parentNode.removeChild(element);
        });

        _this8._dispatch(Shuffle.EventType.REMOVED, { collection: collection });
      };

      // Hide collection first.
      this._toggleFilterClasses({
        visible: [],
        hidden: oldItems
      });

      this._shrink(oldItems);

      this.sort();

      // Update the list of items here because `remove` could be called again
      // with an item that is in the process of being removed.
      this.items = this.items.filter(function (item) {
        return !arrayIncludes(oldItems, item);
      });
      this._updateItemCount();

      this.element.addEventListener(Shuffle.EventType.LAYOUT, handleLayout);
    }

    /**
     * Retrieve a shuffle item by its element.
     * @param {Element} element Element to look for.
     * @return {?ShuffleItem} A shuffle item or null if it's not found.
     */

  }, {
    key: 'getItemByElement',
    value: function getItemByElement(element) {
      for (var i = this.items.length - 1; i >= 0; i--) {
        if (this.items[i].element === element) {
          return this.items[i];
        }
      }

      return null;
    }

    /**
     * Destroys shuffle, removes events, styles, and classes
     */

  }, {
    key: 'destroy',
    value: function destroy() {
      this._cancelMovement();
      window.removeEventListener('resize', this._onResize);

      // Reset container styles
      this.element.classList.remove('shuffle');
      this.element.removeAttribute('style');

      // Reset individual item styles
      this._disposeItems();

      // Null DOM references
      this.items = null;
      this.options.sizer = null;
      this.element = null;
      this._transitions = null;

      // Set a flag so if a debounced resize has been triggered,
      // it can first check if it is actually isDestroyed and not doing anything
      this.isDestroyed = true;
    }

    /**
     * Returns the outer width of an element, optionally including its margins.
     *
     * There are a few different methods for getting the width of an element, none of
     * which work perfectly for all Shuffle's use cases.
     *
     * 1. getBoundingClientRect() `left` and `right` properties.
     *   - Accounts for transform scaled elements, making it useless for Shuffle
     *   elements which have shrunk.
     * 2. The `offsetWidth` property.
     *   - This value stays the same regardless of the elements transform property,
     *   however, it does not return subpixel values.
     * 3. getComputedStyle()
     *   - This works great Chrome, Firefox, Safari, but IE<=11 does not include
     *   padding and border when box-sizing: border-box is set, requiring a feature
     *   test and extra work to add the padding back for IE and other browsers which
     *   follow the W3C spec here.
     *
     * @param {Element} element The element.
     * @param {boolean} [includeMargins] Whether to include margins. Default is false.
     * @return {{width: number, height: number}} The width and height.
     */

  }], [{
    key: 'getSize',
    value: function getSize(element, includeMargins) {
      // Store the styles so that they can be used by others without asking for it again.
      var styles = window.getComputedStyle(element, null);
      var width = getNumberStyle(element, 'width', styles);
      var height = getNumberStyle(element, 'height', styles);

      if (includeMargins) {
        var marginLeft = getNumberStyle(element, 'marginLeft', styles);
        var marginRight = getNumberStyle(element, 'marginRight', styles);
        var marginTop = getNumberStyle(element, 'marginTop', styles);
        var marginBottom = getNumberStyle(element, 'marginBottom', styles);
        width += marginLeft + marginRight;
        height += marginTop + marginBottom;
      }

      return {
        width: width,
        height: height
      };
    }

    /**
     * Change a property or execute a function which will not have a transition
     * @param {Array.<Element>} elements DOM elements that won't be transitioned.
     * @param {Function} callback A function which will be called while transition
     *     is set to 0ms.
     * @private
     */

  }, {
    key: '_skipTransitions',
    value: function _skipTransitions(elements, callback) {
      var zero = '0ms';

      // Save current duration and delay.
      var data = elements.map(function (element) {
        var style = element.style;
        var duration = style.transitionDuration;
        var delay = style.transitionDelay;

        // Set the duration to zero so it happens immediately
        style.transitionDuration = zero;
        style.transitionDelay = zero;

        return {
          duration: duration,
          delay: delay
        };
      });

      callback();

      // Cause reflow.
      elements[0].offsetWidth; // eslint-disable-line no-unused-expressions

      // Put the duration back
      elements.forEach(function (element, i) {
        element.style.transitionDuration = data[i].duration;
        element.style.transitionDelay = data[i].delay;
      });
    }
  }]);
  return Shuffle;
}();

Shuffle.ShuffleItem = ShuffleItem;

Shuffle.ALL_ITEMS = 'all';
Shuffle.FILTER_ATTRIBUTE_KEY = 'groups';

/**
 * @enum {string}
 */
Shuffle.EventType = {
  LAYOUT: 'shuffle:layout',
  REMOVED: 'shuffle:removed'
};

/** @enum {string} */
Shuffle.Classes = Classes;

/**
 * @enum {string}
 */
Shuffle.FilterMode = {
  ANY: 'any',
  ALL: 'all'
};

// Overrideable options
Shuffle.options = {
  // Initial filter group.
  group: Shuffle.ALL_ITEMS,

  // Transition/animation speed (milliseconds).
  speed: 250,

  // CSS easing function to use.
  easing: 'ease',

  // e.g. '.picture-item'.
  itemSelector: '*',

  // Element or selector string. Use an element to determine the size of columns
  // and gutters.
  sizer: null,

  // A static number or function that tells the plugin how wide the gutters
  // between columns are (in pixels).
  gutterWidth: 0,

  // A static number or function that returns a number which tells the plugin
  // how wide the columns are (in pixels).
  columnWidth: 0,

  // If your group is not json, and is comma delimeted, you could set delimeter
  // to ','.
  delimeter: null,

  // Useful for percentage based heights when they might not always be exactly
  // the same (in pixels).
  buffer: 0,

  // Reading the width of elements isn't precise enough and can cause columns to
  // jump between values.
  columnThreshold: 0.01,

  // Shuffle can be isInitialized with a sort object. It is the same object
  // given to the sort method.
  initialSort: null,

  // By default, shuffle will throttle resize events. This can be changed or
  // removed.
  throttle: index$2,

  // How often shuffle can be called on resize (in milliseconds).
  throttleTime: 300,

  // Transition delay offset for each item in milliseconds.
  staggerAmount: 15,

  // Maximum stagger delay in milliseconds.
  staggerAmountMax: 250,

  // Whether to use transforms or absolute positioning.
  useTransforms: true,

  // Affects using an array with filter. e.g. `filter(['one', 'two'])`. With "any",
  // the element passes the test if any of its groups are in the array. With "all",
  // the element only passes if all groups are in the array.
  filterMode: Shuffle.FilterMode.ANY
};

// Expose for testing. Hack at your own risk.
Shuffle.__Point = Point;
Shuffle.__sorter = sorter;
Shuffle.__getColumnSpan = getColumnSpan;
Shuffle.__getAvailablePositions = getAvailablePositions;
Shuffle.__getShortColumn = getShortColumn;

return Shuffle;

})));
//# sourceMappingURL=shuffle.js.map

// TinyColor v1.4.1
// https://github.com/bgrins/TinyColor
// Brian Grinstead, MIT License

(function(Math) {

var trimLeft = /^\s+/,
    trimRight = /\s+$/,
    tinyCounter = 0,
    mathRound = Math.round,
    mathMin = Math.min,
    mathMax = Math.max,
    mathRandom = Math.random;

function tinycolor (color, opts) {

    color = (color) ? color : '';
    opts = opts || { };

    // If input is already a tinycolor, return itself
    if (color instanceof tinycolor) {
       return color;
    }
    // If we are called as a function, call using new instead
    if (!(this instanceof tinycolor)) {
        return new tinycolor(color, opts);
    }

    var rgb = inputToRGB(color);
    this._originalInput = color,
    this._r = rgb.r,
    this._g = rgb.g,
    this._b = rgb.b,
    this._a = rgb.a,
    this._roundA = mathRound(100*this._a) / 100,
    this._format = opts.format || rgb.format;
    this._gradientType = opts.gradientType;

    // Don't let the range of [0,255] come back in [0,1].
    // Potentially lose a little bit of precision here, but will fix issues where
    // .5 gets interpreted as half of the total, instead of half of 1
    // If it was supposed to be 128, this was already taken care of by `inputToRgb`
    if (this._r < 1) { this._r = mathRound(this._r); }
    if (this._g < 1) { this._g = mathRound(this._g); }
    if (this._b < 1) { this._b = mathRound(this._b); }

    this._ok = rgb.ok;
    this._tc_id = tinyCounter++;
}

tinycolor.prototype = {
    isDark: function() {
        return this.getBrightness() < 128;
    },
    isLight: function() {
        return !this.isDark();
    },
    isValid: function() {
        return this._ok;
    },
    getOriginalInput: function() {
      return this._originalInput;
    },
    getFormat: function() {
        return this._format;
    },
    getAlpha: function() {
        return this._a;
    },
    getBrightness: function() {
        //http://www.w3.org/TR/AERT#color-contrast
        var rgb = this.toRgb();
        return (rgb.r * 299 + rgb.g * 587 + rgb.b * 114) / 1000;
    },
    getLuminance: function() {
        //http://www.w3.org/TR/2008/REC-WCAG20-20081211/#relativeluminancedef
        var rgb = this.toRgb();
        var RsRGB, GsRGB, BsRGB, R, G, B;
        RsRGB = rgb.r/255;
        GsRGB = rgb.g/255;
        BsRGB = rgb.b/255;

        if (RsRGB <= 0.03928) {R = RsRGB / 12.92;} else {R = Math.pow(((RsRGB + 0.055) / 1.055), 2.4);}
        if (GsRGB <= 0.03928) {G = GsRGB / 12.92;} else {G = Math.pow(((GsRGB + 0.055) / 1.055), 2.4);}
        if (BsRGB <= 0.03928) {B = BsRGB / 12.92;} else {B = Math.pow(((BsRGB + 0.055) / 1.055), 2.4);}
        return (0.2126 * R) + (0.7152 * G) + (0.0722 * B);
    },
    setAlpha: function(value) {
        this._a = boundAlpha(value);
        this._roundA = mathRound(100*this._a) / 100;
        return this;
    },
    toHsv: function() {
        var hsv = rgbToHsv(this._r, this._g, this._b);
        return { h: hsv.h * 360, s: hsv.s, v: hsv.v, a: this._a };
    },
    toHsvString: function() {
        var hsv = rgbToHsv(this._r, this._g, this._b);
        var h = mathRound(hsv.h * 360), s = mathRound(hsv.s * 100), v = mathRound(hsv.v * 100);
        return (this._a == 1) ?
          "hsv("  + h + ", " + s + "%, " + v + "%)" :
          "hsva(" + h + ", " + s + "%, " + v + "%, "+ this._roundA + ")";
    },
    toHsl: function() {
        var hsl = rgbToHsl(this._r, this._g, this._b);
        return { h: hsl.h * 360, s: hsl.s, l: hsl.l, a: this._a };
    },
    toHslString: function() {
        var hsl = rgbToHsl(this._r, this._g, this._b);
        var h = mathRound(hsl.h * 360), s = mathRound(hsl.s * 100), l = mathRound(hsl.l * 100);
        return (this._a == 1) ?
          "hsl("  + h + ", " + s + "%, " + l + "%)" :
          "hsla(" + h + ", " + s + "%, " + l + "%, "+ this._roundA + ")";
    },
    toHex: function(allow3Char) {
        return rgbToHex(this._r, this._g, this._b, allow3Char);
    },
    toHexString: function(allow3Char) {
        return '#' + this.toHex(allow3Char);
    },
    toHex8: function(allow4Char) {
        return rgbaToHex(this._r, this._g, this._b, this._a, allow4Char);
    },
    toHex8String: function(allow4Char) {
        return '#' + this.toHex8(allow4Char);
    },
    toRgb: function() {
        return { r: mathRound(this._r), g: mathRound(this._g), b: mathRound(this._b), a: this._a };
    },
    toRgbString: function() {
        return (this._a == 1) ?
          "rgb("  + mathRound(this._r) + ", " + mathRound(this._g) + ", " + mathRound(this._b) + ")" :
          "rgba(" + mathRound(this._r) + ", " + mathRound(this._g) + ", " + mathRound(this._b) + ", " + this._roundA + ")";
    },
    toPercentageRgb: function() {
        return { r: mathRound(bound01(this._r, 255) * 100) + "%", g: mathRound(bound01(this._g, 255) * 100) + "%", b: mathRound(bound01(this._b, 255) * 100) + "%", a: this._a };
    },
    toPercentageRgbString: function() {
        return (this._a == 1) ?
          "rgb("  + mathRound(bound01(this._r, 255) * 100) + "%, " + mathRound(bound01(this._g, 255) * 100) + "%, " + mathRound(bound01(this._b, 255) * 100) + "%)" :
          "rgba(" + mathRound(bound01(this._r, 255) * 100) + "%, " + mathRound(bound01(this._g, 255) * 100) + "%, " + mathRound(bound01(this._b, 255) * 100) + "%, " + this._roundA + ")";
    },
    toName: function() {
        if (this._a === 0) {
            return "transparent";
        }

        if (this._a < 1) {
            return false;
        }

        return hexNames[rgbToHex(this._r, this._g, this._b, true)] || false;
    },
    toFilter: function(secondColor) {
        var hex8String = '#' + rgbaToArgbHex(this._r, this._g, this._b, this._a);
        var secondHex8String = hex8String;
        var gradientType = this._gradientType ? "GradientType = 1, " : "";

        if (secondColor) {
            var s = tinycolor(secondColor);
            secondHex8String = '#' + rgbaToArgbHex(s._r, s._g, s._b, s._a);
        }

        return "progid:DXImageTransform.Microsoft.gradient("+gradientType+"startColorstr="+hex8String+",endColorstr="+secondHex8String+")";
    },
    toString: function(format) {
        var formatSet = !!format;
        format = format || this._format;

        var formattedString = false;
        var hasAlpha = this._a < 1 && this._a >= 0;
        var needsAlphaFormat = !formatSet && hasAlpha && (format === "hex" || format === "hex6" || format === "hex3" || format === "hex4" || format === "hex8" || format === "name");

        if (needsAlphaFormat) {
            // Special case for "transparent", all other non-alpha formats
            // will return rgba when there is transparency.
            if (format === "name" && this._a === 0) {
                return this.toName();
            }
            return this.toRgbString();
        }
        if (format === "rgb") {
            formattedString = this.toRgbString();
        }
        if (format === "prgb") {
            formattedString = this.toPercentageRgbString();
        }
        if (format === "hex" || format === "hex6") {
            formattedString = this.toHexString();
        }
        if (format === "hex3") {
            formattedString = this.toHexString(true);
        }
        if (format === "hex4") {
            formattedString = this.toHex8String(true);
        }
        if (format === "hex8") {
            formattedString = this.toHex8String();
        }
        if (format === "name") {
            formattedString = this.toName();
        }
        if (format === "hsl") {
            formattedString = this.toHslString();
        }
        if (format === "hsv") {
            formattedString = this.toHsvString();
        }

        return formattedString || this.toHexString();
    },
    clone: function() {
        return tinycolor(this.toString());
    },

    _applyModification: function(fn, args) {
        var color = fn.apply(null, [this].concat([].slice.call(args)));
        this._r = color._r;
        this._g = color._g;
        this._b = color._b;
        this.setAlpha(color._a);
        return this;
    },
    lighten: function() {
        return this._applyModification(lighten, arguments);
    },
    brighten: function() {
        return this._applyModification(brighten, arguments);
    },
    darken: function() {
        return this._applyModification(darken, arguments);
    },
    desaturate: function() {
        return this._applyModification(desaturate, arguments);
    },
    saturate: function() {
        return this._applyModification(saturate, arguments);
    },
    greyscale: function() {
        return this._applyModification(greyscale, arguments);
    },
    spin: function() {
        return this._applyModification(spin, arguments);
    },

    _applyCombination: function(fn, args) {
        return fn.apply(null, [this].concat([].slice.call(args)));
    },
    analogous: function() {
        return this._applyCombination(analogous, arguments);
    },
    complement: function() {
        return this._applyCombination(complement, arguments);
    },
    monochromatic: function() {
        return this._applyCombination(monochromatic, arguments);
    },
    splitcomplement: function() {
        return this._applyCombination(splitcomplement, arguments);
    },
    triad: function() {
        return this._applyCombination(triad, arguments);
    },
    tetrad: function() {
        return this._applyCombination(tetrad, arguments);
    }
};

// If input is an object, force 1 into "1.0" to handle ratios properly
// String input requires "1.0" as input, so 1 will be treated as 1
tinycolor.fromRatio = function(color, opts) {
    if (typeof color == "object") {
        var newColor = {};
        for (var i in color) {
            if (color.hasOwnProperty(i)) {
                if (i === "a") {
                    newColor[i] = color[i];
                }
                else {
                    newColor[i] = convertToPercentage(color[i]);
                }
            }
        }
        color = newColor;
    }

    return tinycolor(color, opts);
};

// Given a string or object, convert that input to RGB
// Possible string inputs:
//
//     "red"
//     "#f00" or "f00"
//     "#ff0000" or "ff0000"
//     "#ff000000" or "ff000000"
//     "rgb 255 0 0" or "rgb (255, 0, 0)"
//     "rgb 1.0 0 0" or "rgb (1, 0, 0)"
//     "rgba (255, 0, 0, 1)" or "rgba 255, 0, 0, 1"
//     "rgba (1.0, 0, 0, 1)" or "rgba 1.0, 0, 0, 1"
//     "hsl(0, 100%, 50%)" or "hsl 0 100% 50%"
//     "hsla(0, 100%, 50%, 1)" or "hsla 0 100% 50%, 1"
//     "hsv(0, 100%, 100%)" or "hsv 0 100% 100%"
//
function inputToRGB(color) {

    var rgb = { r: 0, g: 0, b: 0 };
    var a = 1;
    var s = null;
    var v = null;
    var l = null;
    var ok = false;
    var format = false;

    if (typeof color == "string") {
        color = stringInputToObject(color);
    }

    if (typeof color == "object") {
        if (isValidCSSUnit(color.r) && isValidCSSUnit(color.g) && isValidCSSUnit(color.b)) {
            rgb = rgbToRgb(color.r, color.g, color.b);
            ok = true;
            format = String(color.r).substr(-1) === "%" ? "prgb" : "rgb";
        }
        else if (isValidCSSUnit(color.h) && isValidCSSUnit(color.s) && isValidCSSUnit(color.v)) {
            s = convertToPercentage(color.s);
            v = convertToPercentage(color.v);
            rgb = hsvToRgb(color.h, s, v);
            ok = true;
            format = "hsv";
        }
        else if (isValidCSSUnit(color.h) && isValidCSSUnit(color.s) && isValidCSSUnit(color.l)) {
            s = convertToPercentage(color.s);
            l = convertToPercentage(color.l);
            rgb = hslToRgb(color.h, s, l);
            ok = true;
            format = "hsl";
        }

        if (color.hasOwnProperty("a")) {
            a = color.a;
        }
    }

    a = boundAlpha(a);

    return {
        ok: ok,
        format: color.format || format,
        r: mathMin(255, mathMax(rgb.r, 0)),
        g: mathMin(255, mathMax(rgb.g, 0)),
        b: mathMin(255, mathMax(rgb.b, 0)),
        a: a
    };
}


// Conversion Functions
// --------------------

// `rgbToHsl`, `rgbToHsv`, `hslToRgb`, `hsvToRgb` modified from:
// <http://mjijackson.com/2008/02/rgb-to-hsl-and-rgb-to-hsv-color-model-conversion-algorithms-in-javascript>

// `rgbToRgb`
// Handle bounds / percentage checking to conform to CSS color spec
// <http://www.w3.org/TR/css3-color/>
// *Assumes:* r, g, b in [0, 255] or [0, 1]
// *Returns:* { r, g, b } in [0, 255]
function rgbToRgb(r, g, b){
    return {
        r: bound01(r, 255) * 255,
        g: bound01(g, 255) * 255,
        b: bound01(b, 255) * 255
    };
}

// `rgbToHsl`
// Converts an RGB color value to HSL.
// *Assumes:* r, g, and b are contained in [0, 255] or [0, 1]
// *Returns:* { h, s, l } in [0,1]
function rgbToHsl(r, g, b) {

    r = bound01(r, 255);
    g = bound01(g, 255);
    b = bound01(b, 255);

    var max = mathMax(r, g, b), min = mathMin(r, g, b);
    var h, s, l = (max + min) / 2;

    if(max == min) {
        h = s = 0; // achromatic
    }
    else {
        var d = max - min;
        s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
        switch(max) {
            case r: h = (g - b) / d + (g < b ? 6 : 0); break;
            case g: h = (b - r) / d + 2; break;
            case b: h = (r - g) / d + 4; break;
        }

        h /= 6;
    }

    return { h: h, s: s, l: l };
}

// `hslToRgb`
// Converts an HSL color value to RGB.
// *Assumes:* h is contained in [0, 1] or [0, 360] and s and l are contained [0, 1] or [0, 100]
// *Returns:* { r, g, b } in the set [0, 255]
function hslToRgb(h, s, l) {
    var r, g, b;

    h = bound01(h, 360);
    s = bound01(s, 100);
    l = bound01(l, 100);

    function hue2rgb(p, q, t) {
        if(t < 0) t += 1;
        if(t > 1) t -= 1;
        if(t < 1/6) return p + (q - p) * 6 * t;
        if(t < 1/2) return q;
        if(t < 2/3) return p + (q - p) * (2/3 - t) * 6;
        return p;
    }

    if(s === 0) {
        r = g = b = l; // achromatic
    }
    else {
        var q = l < 0.5 ? l * (1 + s) : l + s - l * s;
        var p = 2 * l - q;
        r = hue2rgb(p, q, h + 1/3);
        g = hue2rgb(p, q, h);
        b = hue2rgb(p, q, h - 1/3);
    }

    return { r: r * 255, g: g * 255, b: b * 255 };
}

// `rgbToHsv`
// Converts an RGB color value to HSV
// *Assumes:* r, g, and b are contained in the set [0, 255] or [0, 1]
// *Returns:* { h, s, v } in [0,1]
function rgbToHsv(r, g, b) {

    r = bound01(r, 255);
    g = bound01(g, 255);
    b = bound01(b, 255);

    var max = mathMax(r, g, b), min = mathMin(r, g, b);
    var h, s, v = max;

    var d = max - min;
    s = max === 0 ? 0 : d / max;

    if(max == min) {
        h = 0; // achromatic
    }
    else {
        switch(max) {
            case r: h = (g - b) / d + (g < b ? 6 : 0); break;
            case g: h = (b - r) / d + 2; break;
            case b: h = (r - g) / d + 4; break;
        }
        h /= 6;
    }
    return { h: h, s: s, v: v };
}

// `hsvToRgb`
// Converts an HSV color value to RGB.
// *Assumes:* h is contained in [0, 1] or [0, 360] and s and v are contained in [0, 1] or [0, 100]
// *Returns:* { r, g, b } in the set [0, 255]
 function hsvToRgb(h, s, v) {

    h = bound01(h, 360) * 6;
    s = bound01(s, 100);
    v = bound01(v, 100);

    var i = Math.floor(h),
        f = h - i,
        p = v * (1 - s),
        q = v * (1 - f * s),
        t = v * (1 - (1 - f) * s),
        mod = i % 6,
        r = [v, q, p, p, t, v][mod],
        g = [t, v, v, q, p, p][mod],
        b = [p, p, t, v, v, q][mod];

    return { r: r * 255, g: g * 255, b: b * 255 };
}

// `rgbToHex`
// Converts an RGB color to hex
// Assumes r, g, and b are contained in the set [0, 255]
// Returns a 3 or 6 character hex
function rgbToHex(r, g, b, allow3Char) {

    var hex = [
        pad2(mathRound(r).toString(16)),
        pad2(mathRound(g).toString(16)),
        pad2(mathRound(b).toString(16))
    ];

    // Return a 3 character hex if possible
    if (allow3Char && hex[0].charAt(0) == hex[0].charAt(1) && hex[1].charAt(0) == hex[1].charAt(1) && hex[2].charAt(0) == hex[2].charAt(1)) {
        return hex[0].charAt(0) + hex[1].charAt(0) + hex[2].charAt(0);
    }

    return hex.join("");
}

// `rgbaToHex`
// Converts an RGBA color plus alpha transparency to hex
// Assumes r, g, b are contained in the set [0, 255] and
// a in [0, 1]. Returns a 4 or 8 character rgba hex
function rgbaToHex(r, g, b, a, allow4Char) {

    var hex = [
        pad2(mathRound(r).toString(16)),
        pad2(mathRound(g).toString(16)),
        pad2(mathRound(b).toString(16)),
        pad2(convertDecimalToHex(a))
    ];

    // Return a 4 character hex if possible
    if (allow4Char && hex[0].charAt(0) == hex[0].charAt(1) && hex[1].charAt(0) == hex[1].charAt(1) && hex[2].charAt(0) == hex[2].charAt(1) && hex[3].charAt(0) == hex[3].charAt(1)) {
        return hex[0].charAt(0) + hex[1].charAt(0) + hex[2].charAt(0) + hex[3].charAt(0);
    }

    return hex.join("");
}

// `rgbaToArgbHex`
// Converts an RGBA color to an ARGB Hex8 string
// Rarely used, but required for "toFilter()"
function rgbaToArgbHex(r, g, b, a) {

    var hex = [
        pad2(convertDecimalToHex(a)),
        pad2(mathRound(r).toString(16)),
        pad2(mathRound(g).toString(16)),
        pad2(mathRound(b).toString(16))
    ];

    return hex.join("");
}

// `equals`
// Can be called with any tinycolor input
tinycolor.equals = function (color1, color2) {
    if (!color1 || !color2) { return false; }
    return tinycolor(color1).toRgbString() == tinycolor(color2).toRgbString();
};

tinycolor.random = function() {
    return tinycolor.fromRatio({
        r: mathRandom(),
        g: mathRandom(),
        b: mathRandom()
    });
};


// Modification Functions
// ----------------------
// Thanks to less.js for some of the basics here
// <https://github.com/cloudhead/less.js/blob/master/lib/less/functions.js>

function desaturate(color, amount) {
    amount = (amount === 0) ? 0 : (amount || 10);
    var hsl = tinycolor(color).toHsl();
    hsl.s -= amount / 100;
    hsl.s = clamp01(hsl.s);
    return tinycolor(hsl);
}

function saturate(color, amount) {
    amount = (amount === 0) ? 0 : (amount || 10);
    var hsl = tinycolor(color).toHsl();
    hsl.s += amount / 100;
    hsl.s = clamp01(hsl.s);
    return tinycolor(hsl);
}

function greyscale(color) {
    return tinycolor(color).desaturate(100);
}

function lighten (color, amount) {
    amount = (amount === 0) ? 0 : (amount || 10);
    var hsl = tinycolor(color).toHsl();
    hsl.l += amount / 100;
    hsl.l = clamp01(hsl.l);
    return tinycolor(hsl);
}

function brighten(color, amount) {
    amount = (amount === 0) ? 0 : (amount || 10);
    var rgb = tinycolor(color).toRgb();
    rgb.r = mathMax(0, mathMin(255, rgb.r - mathRound(255 * - (amount / 100))));
    rgb.g = mathMax(0, mathMin(255, rgb.g - mathRound(255 * - (amount / 100))));
    rgb.b = mathMax(0, mathMin(255, rgb.b - mathRound(255 * - (amount / 100))));
    return tinycolor(rgb);
}

function darken (color, amount) {
    amount = (amount === 0) ? 0 : (amount || 10);
    var hsl = tinycolor(color).toHsl();
    hsl.l -= amount / 100;
    hsl.l = clamp01(hsl.l);
    return tinycolor(hsl);
}

// Spin takes a positive or negative amount within [-360, 360] indicating the change of hue.
// Values outside of this range will be wrapped into this range.
function spin(color, amount) {
    var hsl = tinycolor(color).toHsl();
    var hue = (hsl.h + amount) % 360;
    hsl.h = hue < 0 ? 360 + hue : hue;
    return tinycolor(hsl);
}

// Combination Functions
// ---------------------
// Thanks to jQuery xColor for some of the ideas behind these
// <https://github.com/infusion/jQuery-xcolor/blob/master/jquery.xcolor.js>

function complement(color) {
    var hsl = tinycolor(color).toHsl();
    hsl.h = (hsl.h + 180) % 360;
    return tinycolor(hsl);
}

function triad(color) {
    var hsl = tinycolor(color).toHsl();
    var h = hsl.h;
    return [
        tinycolor(color),
        tinycolor({ h: (h + 120) % 360, s: hsl.s, l: hsl.l }),
        tinycolor({ h: (h + 240) % 360, s: hsl.s, l: hsl.l })
    ];
}

function tetrad(color) {
    var hsl = tinycolor(color).toHsl();
    var h = hsl.h;
    return [
        tinycolor(color),
        tinycolor({ h: (h + 90) % 360, s: hsl.s, l: hsl.l }),
        tinycolor({ h: (h + 180) % 360, s: hsl.s, l: hsl.l }),
        tinycolor({ h: (h + 270) % 360, s: hsl.s, l: hsl.l })
    ];
}

function splitcomplement(color) {
    var hsl = tinycolor(color).toHsl();
    var h = hsl.h;
    return [
        tinycolor(color),
        tinycolor({ h: (h + 72) % 360, s: hsl.s, l: hsl.l}),
        tinycolor({ h: (h + 216) % 360, s: hsl.s, l: hsl.l})
    ];
}

function analogous(color, results, slices) {
    results = results || 6;
    slices = slices || 30;

    var hsl = tinycolor(color).toHsl();
    var part = 360 / slices;
    var ret = [tinycolor(color)];

    for (hsl.h = ((hsl.h - (part * results >> 1)) + 720) % 360; --results; ) {
        hsl.h = (hsl.h + part) % 360;
        ret.push(tinycolor(hsl));
    }
    return ret;
}

function monochromatic(color, results) {
    results = results || 6;
    var hsv = tinycolor(color).toHsv();
    var h = hsv.h, s = hsv.s, v = hsv.v;
    var ret = [];
    var modification = 1 / results;

    while (results--) {
        ret.push(tinycolor({ h: h, s: s, v: v}));
        v = (v + modification) % 1;
    }

    return ret;
}

// Utility Functions
// ---------------------

tinycolor.mix = function(color1, color2, amount) {
    amount = (amount === 0) ? 0 : (amount || 50);

    var rgb1 = tinycolor(color1).toRgb();
    var rgb2 = tinycolor(color2).toRgb();

    var p = amount / 100;

    var rgba = {
        r: ((rgb2.r - rgb1.r) * p) + rgb1.r,
        g: ((rgb2.g - rgb1.g) * p) + rgb1.g,
        b: ((rgb2.b - rgb1.b) * p) + rgb1.b,
        a: ((rgb2.a - rgb1.a) * p) + rgb1.a
    };

    return tinycolor(rgba);
};


// Readability Functions
// ---------------------
// <http://www.w3.org/TR/2008/REC-WCAG20-20081211/#contrast-ratiodef (WCAG Version 2)

// `contrast`
// Analyze the 2 colors and returns the color contrast defined by (WCAG Version 2)
tinycolor.readability = function(color1, color2) {
    var c1 = tinycolor(color1);
    var c2 = tinycolor(color2);
    return (Math.max(c1.getLuminance(),c2.getLuminance())+0.05) / (Math.min(c1.getLuminance(),c2.getLuminance())+0.05);
};

// `isReadable`
// Ensure that foreground and background color combinations meet WCAG2 guidelines.
// The third argument is an optional Object.
//      the 'level' property states 'AA' or 'AAA' - if missing or invalid, it defaults to 'AA';
//      the 'size' property states 'large' or 'small' - if missing or invalid, it defaults to 'small'.
// If the entire object is absent, isReadable defaults to {level:"AA",size:"small"}.

// *Example*
//    tinycolor.isReadable("#000", "#111") => false
//    tinycolor.isReadable("#000", "#111",{level:"AA",size:"large"}) => false
tinycolor.isReadable = function(color1, color2, wcag2) {
    var readability = tinycolor.readability(color1, color2);
    var wcag2Parms, out;

    out = false;

    wcag2Parms = validateWCAG2Parms(wcag2);
    switch (wcag2Parms.level + wcag2Parms.size) {
        case "AAsmall":
        case "AAAlarge":
            out = readability >= 4.5;
            break;
        case "AAlarge":
            out = readability >= 3;
            break;
        case "AAAsmall":
            out = readability >= 7;
            break;
    }
    return out;

};

// `mostReadable`
// Given a base color and a list of possible foreground or background
// colors for that base, returns the most readable color.
// Optionally returns Black or White if the most readable color is unreadable.
// *Example*
//    tinycolor.mostReadable(tinycolor.mostReadable("#123", ["#124", "#125"],{includeFallbackColors:false}).toHexString(); // "#112255"
//    tinycolor.mostReadable(tinycolor.mostReadable("#123", ["#124", "#125"],{includeFallbackColors:true}).toHexString();  // "#ffffff"
//    tinycolor.mostReadable("#a8015a", ["#faf3f3"],{includeFallbackColors:true,level:"AAA",size:"large"}).toHexString(); // "#faf3f3"
//    tinycolor.mostReadable("#a8015a", ["#faf3f3"],{includeFallbackColors:true,level:"AAA",size:"small"}).toHexString(); // "#ffffff"
tinycolor.mostReadable = function(baseColor, colorList, args) {
    var bestColor = null;
    var bestScore = 0;
    var readability;
    var includeFallbackColors, level, size ;
    args = args || {};
    includeFallbackColors = args.includeFallbackColors ;
    level = args.level;
    size = args.size;

    for (var i= 0; i < colorList.length ; i++) {
        readability = tinycolor.readability(baseColor, colorList[i]);
        if (readability > bestScore) {
            bestScore = readability;
            bestColor = tinycolor(colorList[i]);
        }
    }

    if (tinycolor.isReadable(baseColor, bestColor, {"level":level,"size":size}) || !includeFallbackColors) {
        return bestColor;
    }
    else {
        args.includeFallbackColors=false;
        return tinycolor.mostReadable(baseColor,["#fff", "#000"],args);
    }
};


// Big List of Colors
// ------------------
// <http://www.w3.org/TR/css3-color/#svg-color>
var names = tinycolor.names = {
    aliceblue: "f0f8ff",
    antiquewhite: "faebd7",
    aqua: "0ff",
    aquamarine: "7fffd4",
    azure: "f0ffff",
    beige: "f5f5dc",
    bisque: "ffe4c4",
    black: "000",
    blanchedalmond: "ffebcd",
    blue: "00f",
    blueviolet: "8a2be2",
    brown: "a52a2a",
    burlywood: "deb887",
    burntsienna: "ea7e5d",
    cadetblue: "5f9ea0",
    chartreuse: "7fff00",
    chocolate: "d2691e",
    coral: "ff7f50",
    cornflowerblue: "6495ed",
    cornsilk: "fff8dc",
    crimson: "dc143c",
    cyan: "0ff",
    darkblue: "00008b",
    darkcyan: "008b8b",
    darkgoldenrod: "b8860b",
    darkgray: "a9a9a9",
    darkgreen: "006400",
    darkgrey: "a9a9a9",
    darkkhaki: "bdb76b",
    darkmagenta: "8b008b",
    darkolivegreen: "556b2f",
    darkorange: "ff8c00",
    darkorchid: "9932cc",
    darkred: "8b0000",
    darksalmon: "e9967a",
    darkseagreen: "8fbc8f",
    darkslateblue: "483d8b",
    darkslategray: "2f4f4f",
    darkslategrey: "2f4f4f",
    darkturquoise: "00ced1",
    darkviolet: "9400d3",
    deeppink: "ff1493",
    deepskyblue: "00bfff",
    dimgray: "696969",
    dimgrey: "696969",
    dodgerblue: "1e90ff",
    firebrick: "b22222",
    floralwhite: "fffaf0",
    forestgreen: "228b22",
    fuchsia: "f0f",
    gainsboro: "dcdcdc",
    ghostwhite: "f8f8ff",
    gold: "ffd700",
    goldenrod: "daa520",
    gray: "808080",
    green: "008000",
    greenyellow: "adff2f",
    grey: "808080",
    honeydew: "f0fff0",
    hotpink: "ff69b4",
    indianred: "cd5c5c",
    indigo: "4b0082",
    ivory: "fffff0",
    khaki: "f0e68c",
    lavender: "e6e6fa",
    lavenderblush: "fff0f5",
    lawngreen: "7cfc00",
    lemonchiffon: "fffacd",
    lightblue: "add8e6",
    lightcoral: "f08080",
    lightcyan: "e0ffff",
    lightgoldenrodyellow: "fafad2",
    lightgray: "d3d3d3",
    lightgreen: "90ee90",
    lightgrey: "d3d3d3",
    lightpink: "ffb6c1",
    lightsalmon: "ffa07a",
    lightseagreen: "20b2aa",
    lightskyblue: "87cefa",
    lightslategray: "789",
    lightslategrey: "789",
    lightsteelblue: "b0c4de",
    lightyellow: "ffffe0",
    lime: "0f0",
    limegreen: "32cd32",
    linen: "faf0e6",
    magenta: "f0f",
    maroon: "800000",
    mediumaquamarine: "66cdaa",
    mediumblue: "0000cd",
    mediumorchid: "ba55d3",
    mediumpurple: "9370db",
    mediumseagreen: "3cb371",
    mediumslateblue: "7b68ee",
    mediumspringgreen: "00fa9a",
    mediumturquoise: "48d1cc",
    mediumvioletred: "c71585",
    midnightblue: "191970",
    mintcream: "f5fffa",
    mistyrose: "ffe4e1",
    moccasin: "ffe4b5",
    navajowhite: "ffdead",
    navy: "000080",
    oldlace: "fdf5e6",
    olive: "808000",
    olivedrab: "6b8e23",
    orange: "ffa500",
    orangered: "ff4500",
    orchid: "da70d6",
    palegoldenrod: "eee8aa",
    palegreen: "98fb98",
    paleturquoise: "afeeee",
    palevioletred: "db7093",
    papayawhip: "ffefd5",
    peachpuff: "ffdab9",
    peru: "cd853f",
    pink: "ffc0cb",
    plum: "dda0dd",
    powderblue: "b0e0e6",
    purple: "800080",
    rebeccapurple: "663399",
    red: "f00",
    rosybrown: "bc8f8f",
    royalblue: "4169e1",
    saddlebrown: "8b4513",
    salmon: "fa8072",
    sandybrown: "f4a460",
    seagreen: "2e8b57",
    seashell: "fff5ee",
    sienna: "a0522d",
    silver: "c0c0c0",
    skyblue: "87ceeb",
    slateblue: "6a5acd",
    slategray: "708090",
    slategrey: "708090",
    snow: "fffafa",
    springgreen: "00ff7f",
    steelblue: "4682b4",
    tan: "d2b48c",
    teal: "008080",
    thistle: "d8bfd8",
    tomato: "ff6347",
    turquoise: "40e0d0",
    violet: "ee82ee",
    wheat: "f5deb3",
    white: "fff",
    whitesmoke: "f5f5f5",
    yellow: "ff0",
    yellowgreen: "9acd32"
};

// Make it easy to access colors via `hexNames[hex]`
var hexNames = tinycolor.hexNames = flip(names);


// Utilities
// ---------

// `{ 'name1': 'val1' }` becomes `{ 'val1': 'name1' }`
function flip(o) {
    var flipped = { };
    for (var i in o) {
        if (o.hasOwnProperty(i)) {
            flipped[o[i]] = i;
        }
    }
    return flipped;
}

// Return a valid alpha value [0,1] with all invalid values being set to 1
function boundAlpha(a) {
    a = parseFloat(a);

    if (isNaN(a) || a < 0 || a > 1) {
        a = 1;
    }

    return a;
}

// Take input from [0, n] and return it as [0, 1]
function bound01(n, max) {
    if (isOnePointZero(n)) { n = "100%"; }

    var processPercent = isPercentage(n);
    n = mathMin(max, mathMax(0, parseFloat(n)));

    // Automatically convert percentage into number
    if (processPercent) {
        n = parseInt(n * max, 10) / 100;
    }

    // Handle floating point rounding errors
    if ((Math.abs(n - max) < 0.000001)) {
        return 1;
    }

    // Convert into [0, 1] range if it isn't already
    return (n % max) / parseFloat(max);
}

// Force a number between 0 and 1
function clamp01(val) {
    return mathMin(1, mathMax(0, val));
}

// Parse a base-16 hex value into a base-10 integer
function parseIntFromHex(val) {
    return parseInt(val, 16);
}

// Need to handle 1.0 as 100%, since once it is a number, there is no difference between it and 1
// <http://stackoverflow.com/questions/7422072/javascript-how-to-detect-number-as-a-decimal-including-1-0>
function isOnePointZero(n) {
    return typeof n == "string" && n.indexOf('.') != -1 && parseFloat(n) === 1;
}

// Check to see if string passed in is a percentage
function isPercentage(n) {
    return typeof n === "string" && n.indexOf('%') != -1;
}

// Force a hex value to have 2 characters
function pad2(c) {
    return c.length == 1 ? '0' + c : '' + c;
}

// Replace a decimal with it's percentage value
function convertToPercentage(n) {
    if (n <= 1) {
        n = (n * 100) + "%";
    }

    return n;
}

// Converts a decimal to a hex value
function convertDecimalToHex(d) {
    return Math.round(parseFloat(d) * 255).toString(16);
}
// Converts a hex value to a decimal
function convertHexToDecimal(h) {
    return (parseIntFromHex(h) / 255);
}

var matchers = (function() {

    // <http://www.w3.org/TR/css3-values/#integers>
    var CSS_INTEGER = "[-\\+]?\\d+%?";

    // <http://www.w3.org/TR/css3-values/#number-value>
    var CSS_NUMBER = "[-\\+]?\\d*\\.\\d+%?";

    // Allow positive/negative integer/number.  Don't capture the either/or, just the entire outcome.
    var CSS_UNIT = "(?:" + CSS_NUMBER + ")|(?:" + CSS_INTEGER + ")";

    // Actual matching.
    // Parentheses and commas are optional, but not required.
    // Whitespace can take the place of commas or opening paren
    var PERMISSIVE_MATCH3 = "[\\s|\\(]+(" + CSS_UNIT + ")[,|\\s]+(" + CSS_UNIT + ")[,|\\s]+(" + CSS_UNIT + ")\\s*\\)?";
    var PERMISSIVE_MATCH4 = "[\\s|\\(]+(" + CSS_UNIT + ")[,|\\s]+(" + CSS_UNIT + ")[,|\\s]+(" + CSS_UNIT + ")[,|\\s]+(" + CSS_UNIT + ")\\s*\\)?";

    return {
        CSS_UNIT: new RegExp(CSS_UNIT),
        rgb: new RegExp("rgb" + PERMISSIVE_MATCH3),
        rgba: new RegExp("rgba" + PERMISSIVE_MATCH4),
        hsl: new RegExp("hsl" + PERMISSIVE_MATCH3),
        hsla: new RegExp("hsla" + PERMISSIVE_MATCH4),
        hsv: new RegExp("hsv" + PERMISSIVE_MATCH3),
        hsva: new RegExp("hsva" + PERMISSIVE_MATCH4),
        hex3: /^#?([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})$/,
        hex6: /^#?([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})$/,
        hex4: /^#?([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})$/,
        hex8: /^#?([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})$/
    };
})();

// `isValidCSSUnit`
// Take in a single string / number and check to see if it looks like a CSS unit
// (see `matchers` above for definition).
function isValidCSSUnit(color) {
    return !!matchers.CSS_UNIT.exec(color);
}

// `stringInputToObject`
// Permissive string parsing.  Take in a number of formats, and output an object
// based on detected format.  Returns `{ r, g, b }` or `{ h, s, l }` or `{ h, s, v}`
function stringInputToObject(color) {

    color = color.replace(trimLeft,'').replace(trimRight, '').toLowerCase();
    var named = false;
    if (names[color]) {
        color = names[color];
        named = true;
    }
    else if (color == 'transparent') {
        return { r: 0, g: 0, b: 0, a: 0, format: "name" };
    }

    // Try to match string input using regular expressions.
    // Keep most of the number bounding out of this function - don't worry about [0,1] or [0,100] or [0,360]
    // Just return an object and let the conversion functions handle that.
    // This way the result will be the same whether the tinycolor is initialized with string or object.
    var match;
    if ((match = matchers.rgb.exec(color))) {
        return { r: match[1], g: match[2], b: match[3] };
    }
    if ((match = matchers.rgba.exec(color))) {
        return { r: match[1], g: match[2], b: match[3], a: match[4] };
    }
    if ((match = matchers.hsl.exec(color))) {
        return { h: match[1], s: match[2], l: match[3] };
    }
    if ((match = matchers.hsla.exec(color))) {
        return { h: match[1], s: match[2], l: match[3], a: match[4] };
    }
    if ((match = matchers.hsv.exec(color))) {
        return { h: match[1], s: match[2], v: match[3] };
    }
    if ((match = matchers.hsva.exec(color))) {
        return { h: match[1], s: match[2], v: match[3], a: match[4] };
    }
    if ((match = matchers.hex8.exec(color))) {
        return {
            r: parseIntFromHex(match[1]),
            g: parseIntFromHex(match[2]),
            b: parseIntFromHex(match[3]),
            a: convertHexToDecimal(match[4]),
            format: named ? "name" : "hex8"
        };
    }
    if ((match = matchers.hex6.exec(color))) {
        return {
            r: parseIntFromHex(match[1]),
            g: parseIntFromHex(match[2]),
            b: parseIntFromHex(match[3]),
            format: named ? "name" : "hex"
        };
    }
    if ((match = matchers.hex4.exec(color))) {
        return {
            r: parseIntFromHex(match[1] + '' + match[1]),
            g: parseIntFromHex(match[2] + '' + match[2]),
            b: parseIntFromHex(match[3] + '' + match[3]),
            a: convertHexToDecimal(match[4] + '' + match[4]),
            format: named ? "name" : "hex8"
        };
    }
    if ((match = matchers.hex3.exec(color))) {
        return {
            r: parseIntFromHex(match[1] + '' + match[1]),
            g: parseIntFromHex(match[2] + '' + match[2]),
            b: parseIntFromHex(match[3] + '' + match[3]),
            format: named ? "name" : "hex"
        };
    }

    return false;
}

function validateWCAG2Parms(parms) {
    // return valid WCAG2 parms for isReadable.
    // If input parms are invalid, return {"level":"AA", "size":"small"}
    var level, size;
    parms = parms || {"level":"AA", "size":"small"};
    level = (parms.level || "AA").toUpperCase();
    size = (parms.size || "small").toLowerCase();
    if (level !== "AA" && level !== "AAA") {
        level = "AA";
    }
    if (size !== "small" && size !== "large") {
        size = "small";
    }
    return {"level":level, "size":size};
}

// Node: Export function
if (typeof module !== "undefined" && module.exports) {
    module.exports = tinycolor;
}
// AMD/requirejs: Define the module
else if (typeof define === 'function' && define.amd) {
    define(function () {return tinycolor;});
}
// Browser: Expose to window
else {
    window.tinycolor = tinycolor;
}

})(Math);




String.prototype.hashCode = function(){
    // djb2 hash algorithm
    var hash = 5381;
    for (i = 0; i < this.length; i++) {
        char = this.charCodeAt(i);
        hash = ((hash << 5) + hash) + char; /* hash * 33 + c */
    }
    return hash >>> 0;
};

var Color = tinycolor;


var Shuffle = window.shuffle;

var shuffle = new Shuffle(document.querySelector('.tile-container'), {
  group: shuffle.ALL_ITEMS,
  itemSelector: '.tile',
  gutterWidth: 16,
  columnWidth: 188,
  buffer: 1,
  delimeter: ",",
  useTransforms: false,
});

var filterTiles = function(tag) {
    shuffle.filter(location.hash.slice(1));
};

window.onhashchange = filterTiles;

var getUrlParts = function(baseUrl) {
    var urlParts = {
        domain: "",
        before: "",
        after: ""
    };
    var url = new URL(baseUrl);
    var host = url.host;
    urlParts.domain = host.replace(/^www\./i, "");

    if (host.match(/^\d+\.\d+\.\d+\.\d+$/)) {
            urlParts.domain = host;
        return urlParts;
    } else if (host.match(/^(\d+\.\d+\.\d+\.\d+)(:(\d+))?$/)) {
        hostParts = host.match(/^(\d+\.\d+\.\d+\.\d+)(:(\d+))?$/);
        urlParts.domain = hostParts[1];
        urlParts.after = hostParts[3];
        return urlParts;
    }

    var hostParts = urlParts.domain.split(".");
    var longestPartIndex = 0;
    for (var i = 1; i < hostParts.length - 1; i++) {
        if (hostParts[i].length > hostParts[longestPartIndex].length) {
            longestPartIndex = i;
        }
    }

    urlParts.domain = hostParts[longestPartIndex];
    urlParts.before = hostParts.slice(0, longestPartIndex).join(".");
    urlParts.after = hostParts.slice(longestPartIndex + 1).join(".");

    if(!urlParts.domain && url.pathname) {
      urlParts.domain = url.pathname.split("/").filter(Boolean).pop();
    }
    return urlParts;
};

var fitText = function(text, boxWidth, boxHeight) {
    var resizer = document.createElement("div");
    resizer.style.visibility = "hidden";
    resizer.style.position = "absolute";
    document.body.appendChild(resizer);

    var size = 40;

    resizer.innerHTML = text;
    resizer.style.fontSize = size;
    while (resizer.offsetWidth > boxWidth) {
        size = size - 1;
        resizer.style.fontSize = size;
    }

    var textInfo = {
        size: size,
        width: resizer.offsetWidth,
        height: resizer.offsetHeight
    };
    resizer.remove();
    return textInfo;
};


var getTileColor = function(domain) {
    var colorMap = [
  "#B42424",
  "#C83D1D",
  "#BB7231",
  "#E06B00",
  "#55931F",
  "#1C941B",
  "#189365",
  "#189196",
  "#2D85A4",
  "#2B6C90",
  "#205396",
  "#39448F",
  "#55338E",
  "#683089",
  "#963A97",
  "#A43343",
  "#982F2F",
  "#D30000",
  "#E54C29",
  "#DA7E2C",
  // "#F0C92C",
  "#73B43A",
  "#3AB43A",
  "#3AB487",
  "#3AB0B4",
  "#47A6C7",
  "#3A88B4",
  "#3A6FB4",
  "#3A4AB4",
  "#673AB4",
  "#863AB4",
  "#C846C9",
  "#C44A5B",
  "#AA4444",
  "#E84545",
  "#FF6946",
  "#EC9344",
  // "#F4D34F",
  // "#8BD34B",
  // "#4AD449",
  // "#6FDFB5",
  // "#45D3D9",
  // "#5CC4E8",
  "#3CA4DF",
  "#3A83E3",
  "#4056E3",
  "#9058F0",
  "#B467E2",
  "#DF7CDF",
  "#E5576B",
  "#D35A5A",
  // "#FF9C44",
  // "#F2B722",
  // "#4DCC7B",
  "#3DC53D",
  "#2DBBB1",
  "#5E95D5",
  // "#41BBF5",
  "#5E5BE7",
  "#1B7EFF",
  "#5F74FF",
  "#8A45FF",
  "#B856F3",
  "#DD66DD"
];

    return colorMap[domain.hashCode() % colorMap.length];

};

var renderImgTile = function(tile) {
    tile.innerHTML = "";

    var bgColor = tile.getAttribute("data-bg-color");
    if (!bgColor) {
        bgColor = "rgba(255,255,255,.8)";
    }
    bgColor = Color(bgColor);
    bgColor.setAlpha(0.8);
    tile.style.backgroundColor = bgColor;

    var img = new Image();
    img.src = tile.getAttribute("data-img");
    img.className = "logo";
    tile.appendChild(img);
};

var renderPlainTile = function(tile) {
    var urlParts = getUrlParts(tile.getAttribute("data-url"));
    tile.innerHTML = "";

    var bgColor = tile.getAttribute("data-bg-color");
    if (!bgColor) {
        bgColor = "rgba(255,255,255,.8)";
    }
    bgColor = Color(bgColor);
    bgColor.setAlpha(0.8);
    tile.style.backgroundColor = bgColor;

    var txtColor = tile.getAttribute("data-txt-color");
    if (!txtColor) {
        txtColor = getTileColor(urlParts.domain);
        if (bgColor.isDark()) {
            tile.style.color = "white";
        }
    }
    txtColor = Color(txtColor);
    tile.style.color = txtColor;

    var boxWidth = 188, boxHeight = 120;
    var margin = 8;

    var textInfo = fitText(urlParts.domain, boxWidth-margin*2, boxHeight);

    var domainDiv = document.createElement("div");
    domainDiv.style.fontSize = textInfo.size;
    domainDiv.style.position = "absolute";
    tile.appendChild(domainDiv);

    var beforeDiv = document.createElement("div");
    beforeDiv.innerHTML = urlParts.before;
    // original forumla is 7/18*size-10
    beforeDiv.style.top = 0.35*textInfo.size-10;
    beforeDiv.className = "pre-domain";
    beforeDiv.style.textShadow = "-1px 0 "+bgColor+",0 1px "+bgColor+",1px 0 "+bgColor+",0 -1px "+bgColor;

    var afterDiv = document.createElement("div");
    afterDiv.innerHTML = urlParts.after;
    afterDiv.style.top = textInfo.size-0.05*textInfo.size;
    afterDiv.className = "post-domain";
    afterDiv.style.textShadow = "-1px 0 "+bgColor+",0 1px "+bgColor+",1px 0 "+bgColor+",0 -1px "+bgColor;


    domainDiv.appendChild(beforeDiv);
    domainDiv.append(urlParts.domain);
    domainDiv.appendChild(afterDiv);

    var top = (boxHeight + margin)/2 - domainDiv.clientHeight/2;
    var left = (boxWidth + margin)/2 + margin - domainDiv.clientWidth/2;
    domainDiv.style.top = top;
    domainDiv.style.left = left;

    // console.log(urlParts.domain+"="+urlParts.domain.hashCode().toString());
};

var renderTiles = function() {
    var tiles = document.getElementsByClassName("tile-box");
    for(var i = 0; i < tiles.length; i++)
    {
        try {
            if (tiles.item(i).getAttribute("data-img")) {
                renderImgTile(tiles.item(i));
            } else {
                renderPlainTile(tiles.item(i));
            }
        }
        catch(err) {
            console.log("err:"+err);
        }
    }
};

renderTiles();

var getBackgroundImages = function() {
    var backgrounds = document.getElementsByTagName("background");
    var images = [];
    if (backgrounds.length > 0) {
        var imgString = backgrounds[0].getAttribute("data-backgrounds");
        images = imgString.split(/[\s,]+/).filter(Boolean);
    }
    return images;
};

var preloadBackgrounds = function() {
    var images = getBackgroundImages();
    for(var i = 0; i < images.length; i++)
    {
        // caches images, avoiding white flash between background replacements
        new Image().src = images[i];
    }
};

var rotateBackground = function(count) {
    if (count === undefined || count === null) {
        count = 0;
    }

    var images = getBackgroundImages();
    if (images.length > 0) {
        count = (count+1) % images.length;
        // console.log("rotating background to "+count);

        document.body.style.background = 'url("' + images[count] +'")';
        document.body.style.backgroundSize = "cover";
        if (images.length > 1) {
            setTimeout(rotateBackground.bind(null, count), 30000);
        }
    }
};
preloadBackgrounds();
rotateBackground();