flickity/dist/flickity.pkgd.js

Touch, responsive, flickable carousels

/*!
 * Flickity PACKAGED v2.0.6
 * Touch, responsive, flickable carousels
 *
 * Licensed GPLv3 for open source use
 * or Flickity Commercial License for commercial use
 *
 * http://flickity.metafizzy.co
 * Copyright 2016 Metafizzy
 */

/**
 * Bridget makes jQuery widgets
 * v2.0.1
 * MIT license
 */

/* jshint browser: true, strict: true, undef: true, unused: true */

( function( window, factory ) {
  // universal module definition
  /*jshint strict: false */ /* globals define, module, require */
  if ( typeof define == 'function' && define.amd ) {
    // AMD
    define( 'jquery-bridget/jquery-bridget',[ 'jquery' ], function( jQuery ) {
      return factory( window, jQuery );
    });
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS
    module.exports = factory(
      window,
      require('jquery')
    );
  } else {
    // browser global
    window.jQueryBridget = factory(
      window,
      window.jQuery
    );
  }

}( window, function factory( window, jQuery ) {
'use strict';

// ----- utils ----- //

var arraySlice = Array.prototype.slice;

// helper function for logging errors
// $.error breaks jQuery chaining
var console = window.console;
var logError = typeof console == 'undefined' ? function() {} :
  function( message ) {
    console.error( message );
  };

// ----- jQueryBridget ----- //

function jQueryBridget( namespace, PluginClass, $ ) {
  $ = $ || jQuery || window.jQuery;
  if ( !$ ) {
    return;
  }

  // add option method -> $().plugin('option', {...})
  if ( !PluginClass.prototype.option ) {
    // option setter
    PluginClass.prototype.option = function( opts ) {
      // bail out if not an object
      if ( !$.isPlainObject( opts ) ){
        return;
      }
      this.options = $.extend( true, this.options, opts );
    };
  }

  // make jQuery plugin
  $.fn[ namespace ] = function( arg0 /*, arg1 */ ) {
    if ( typeof arg0 == 'string' ) {
      // method call $().plugin( 'methodName', { options } )
      // shift arguments by 1
      var args = arraySlice.call( arguments, 1 );
      return methodCall( this, arg0, args );
    }
    // just $().plugin({ options })
    plainCall( this, arg0 );
    return this;
  };

  // $().plugin('methodName')
  function methodCall( $elems, methodName, args ) {
    var returnValue;
    var pluginMethodStr = '$().' + namespace + '("' + methodName + '")';

    $elems.each( function( i, elem ) {
      // get instance
      var instance = $.data( elem, namespace );
      if ( !instance ) {
        logError( namespace + ' not initialized. Cannot call methods, i.e. ' +
          pluginMethodStr );
        return;
      }

      var method = instance[ methodName ];
      if ( !method || methodName.charAt(0) == '_' ) {
        logError( pluginMethodStr + ' is not a valid method' );
        return;
      }

      // apply method, get return value
      var value = method.apply( instance, args );
      // set return value if value is returned, use only first value
      returnValue = returnValue === undefined ? value : returnValue;
    });

    return returnValue !== undefined ? returnValue : $elems;
  }

  function plainCall( $elems, options ) {
    $elems.each( function( i, elem ) {
      var instance = $.data( elem, namespace );
      if ( instance ) {
        // set options & init
        instance.option( options );
        instance._init();
      } else {
        // initialize new instance
        instance = new PluginClass( elem, options );
        $.data( elem, namespace, instance );
      }
    });
  }

  updateJQuery( $ );

}

// ----- updateJQuery ----- //

// set $.bridget for v1 backwards compatibility
function updateJQuery( $ ) {
  if ( !$ || ( $ && $.bridget ) ) {
    return;
  }
  $.bridget = jQueryBridget;
}

updateJQuery( jQuery || window.jQuery );

// -----  ----- //

return jQueryBridget;

}));

/**
 * EvEmitter v1.0.3
 * Lil' event emitter
 * MIT License
 */

/* jshint unused: true, undef: true, strict: true */

( function( global, factory ) {
  // universal module definition
  /* jshint strict: false */ /* globals define, module, window */
  if ( typeof define == 'function' && define.amd ) {
    // AMD - RequireJS
    define( 'ev-emitter/ev-emitter',factory );
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS - Browserify, Webpack
    module.exports = factory();
  } else {
    // Browser globals
    global.EvEmitter = factory();
  }

}( typeof window != 'undefined' ? window : this, function() {



function EvEmitter() {}

var proto = EvEmitter.prototype;

proto.on = function( eventName, listener ) {
  if ( !eventName || !listener ) {
    return;
  }
  // set events hash
  var events = this._events = this._events || {};
  // set listeners array
  var listeners = events[ eventName ] = events[ eventName ] || [];
  // only add once
  if ( listeners.indexOf( listener ) == -1 ) {
    listeners.push( listener );
  }

  return this;
};

proto.once = function( eventName, listener ) {
  if ( !eventName || !listener ) {
    return;
  }
  // add event
  this.on( eventName, listener );
  // set once flag
  // set onceEvents hash
  var onceEvents = this._onceEvents = this._onceEvents || {};
  // set onceListeners object
  var onceListeners = onceEvents[ eventName ] = onceEvents[ eventName ] || {};
  // set flag
  onceListeners[ listener ] = true;

  return this;
};

proto.off = function( eventName, listener ) {
  var listeners = this._events && this._events[ eventName ];
  if ( !listeners || !listeners.length ) {
    return;
  }
  var index = listeners.indexOf( listener );
  if ( index != -1 ) {
    listeners.splice( index, 1 );
  }

  return this;
};

proto.emitEvent = function( eventName, args ) {
  var listeners = this._events && this._events[ eventName ];
  if ( !listeners || !listeners.length ) {
    return;
  }
  var i = 0;
  var listener = listeners[i];
  args = args || [];
  // once stuff
  var onceListeners = this._onceEvents && this._onceEvents[ eventName ];

  while ( listener ) {
    var isOnce = onceListeners && onceListeners[ listener ];
    if ( isOnce ) {
      // remove listener
      // remove before trigger to prevent recursion
      this.off( eventName, listener );
      // unset once flag
      delete onceListeners[ listener ];
    }
    // trigger listener
    listener.apply( this, args );
    // get next listener
    i += isOnce ? 0 : 1;
    listener = listeners[i];
  }

  return this;
};

return EvEmitter;

}));

/*!
 * getSize v2.0.2
 * measure size of elements
 * MIT license
 */

/*jshint browser: true, strict: true, undef: true, unused: true */
/*global define: false, module: false, console: false */

( function( window, factory ) {
  'use strict';

  if ( typeof define == 'function' && define.amd ) {
    // AMD
    define( 'get-size/get-size',[],function() {
      return factory();
    });
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS
    module.exports = factory();
  } else {
    // browser global
    window.getSize = factory();
  }

})( window, function factory() {
'use strict';

// -------------------------- helpers -------------------------- //

// get a number from a string, not a percentage
function getStyleSize( value ) {
  var num = parseFloat( value );
  // not a percent like '100%', and a number
  var isValid = value.indexOf('%') == -1 && !isNaN( num );
  return isValid && num;
}

function noop() {}

var logError = typeof console == 'undefined' ? noop :
  function( message ) {
    console.error( message );
  };

// -------------------------- measurements -------------------------- //

var measurements = [
  'paddingLeft',
  'paddingRight',
  'paddingTop',
  'paddingBottom',
  'marginLeft',
  'marginRight',
  'marginTop',
  'marginBottom',
  'borderLeftWidth',
  'borderRightWidth',
  'borderTopWidth',
  'borderBottomWidth'
];

var measurementsLength = measurements.length;

function getZeroSize() {
  var size = {
    width: 0,
    height: 0,
    innerWidth: 0,
    innerHeight: 0,
    outerWidth: 0,
    outerHeight: 0
  };
  for ( var i=0; i < measurementsLength; i++ ) {
    var measurement = measurements[i];
    size[ measurement ] = 0;
  }
  return size;
}

// -------------------------- getStyle -------------------------- //

/**
 * getStyle, get style of element, check for Firefox bug
 * https://bugzilla.mozilla.org/show_bug.cgi?id=548397
 */
function getStyle( elem ) {
  var style = getComputedStyle( elem );
  if ( !style ) {
    logError( 'Style returned ' + style +
      '. Are you running this code in a hidden iframe on Firefox? ' +
      'See http://bit.ly/getsizebug1' );
  }
  return style;
}

// -------------------------- setup -------------------------- //

var isSetup = false;

var isBoxSizeOuter;

/**
 * setup
 * check isBoxSizerOuter
 * do on first getSize() rather than on page load for Firefox bug
 */
function setup() {
  // setup once
  if ( isSetup ) {
    return;
  }
  isSetup = true;

  // -------------------------- box sizing -------------------------- //

  /**
   * WebKit measures the outer-width on style.width on border-box elems
   * IE & Firefox<29 measures the inner-width
   */
  var div = document.createElement('div');
  div.style.width = '200px';
  div.style.padding = '1px 2px 3px 4px';
  div.style.borderStyle = 'solid';
  div.style.borderWidth = '1px 2px 3px 4px';
  div.style.boxSizing = 'border-box';

  var body = document.body || document.documentElement;
  body.appendChild( div );
  var style = getStyle( div );

  getSize.isBoxSizeOuter = isBoxSizeOuter = getStyleSize( style.width ) == 200;
  body.removeChild( div );

}

// -------------------------- getSize -------------------------- //

function getSize( elem ) {
  setup();

  // use querySeletor if elem is string
  if ( typeof elem == 'string' ) {
    elem = document.querySelector( elem );
  }

  // do not proceed on non-objects
  if ( !elem || typeof elem != 'object' || !elem.nodeType ) {
    return;
  }

  var style = getStyle( elem );

  // if hidden, everything is 0
  if ( style.display == 'none' ) {
    return getZeroSize();
  }

  var size = {};
  size.width = elem.offsetWidth;
  size.height = elem.offsetHeight;

  var isBorderBox = size.isBorderBox = style.boxSizing == 'border-box';

  // get all measurements
  for ( var i=0; i < measurementsLength; i++ ) {
    var measurement = measurements[i];
    var value = style[ measurement ];
    var num = parseFloat( value );
    // any 'auto', 'medium' value will be 0
    size[ measurement ] = !isNaN( num ) ? num : 0;
  }

  var paddingWidth = size.paddingLeft + size.paddingRight;
  var paddingHeight = size.paddingTop + size.paddingBottom;
  var marginWidth = size.marginLeft + size.marginRight;
  var marginHeight = size.marginTop + size.marginBottom;
  var borderWidth = size.borderLeftWidth + size.borderRightWidth;
  var borderHeight = size.borderTopWidth + size.borderBottomWidth;

  var isBorderBoxSizeOuter = isBorderBox && isBoxSizeOuter;

  // overwrite width and height if we can get it from style
  var styleWidth = getStyleSize( style.width );
  if ( styleWidth !== false ) {
    size.width = styleWidth +
      // add padding and border unless it's already including it
      ( isBorderBoxSizeOuter ? 0 : paddingWidth + borderWidth );
  }

  var styleHeight = getStyleSize( style.height );
  if ( styleHeight !== false ) {
    size.height = styleHeight +
      // add padding and border unless it's already including it
      ( isBorderBoxSizeOuter ? 0 : paddingHeight + borderHeight );
  }

  size.innerWidth = size.width - ( paddingWidth + borderWidth );
  size.innerHeight = size.height - ( paddingHeight + borderHeight );

  size.outerWidth = size.width + marginWidth;
  size.outerHeight = size.height + marginHeight;

  return size;
}

return getSize;

});

/**
 * matchesSelector v2.0.2
 * matchesSelector( element, '.selector' )
 * MIT license
 */

/*jshint browser: true, strict: true, undef: true, unused: true */

( function( window, factory ) {
  /*global define: false, module: false */
  'use strict';
  // universal module definition
  if ( typeof define == 'function' && define.amd ) {
    // AMD
    define( 'desandro-matches-selector/matches-selector',factory );
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS
    module.exports = factory();
  } else {
    // browser global
    window.matchesSelector = factory();
  }

}( window, function factory() {
  'use strict';

  var matchesMethod = ( function() {
    var ElemProto = window.Element.prototype;
    // check for the standard method name first
    if ( ElemProto.matches ) {
      return 'matches';
    }
    // check un-prefixed
    if ( ElemProto.matchesSelector ) {
      return 'matchesSelector';
    }
    // check vendor prefixes
    var prefixes = [ 'webkit', 'moz', 'ms', 'o' ];

    for ( var i=0; i < prefixes.length; i++ ) {
      var prefix = prefixes[i];
      var method = prefix + 'MatchesSelector';
      if ( ElemProto[ method ] ) {
        return method;
      }
    }
  })();

  return function matchesSelector( elem, selector ) {
    return elem[ matchesMethod ]( selector );
  };

}));

/**
 * Fizzy UI utils v2.0.5
 * MIT license
 */

/*jshint browser: true, undef: true, unused: true, strict: true */

( function( window, factory ) {
  // universal module definition
  /*jshint strict: false */ /*globals define, module, require */

  if ( typeof define == 'function' && define.amd ) {
    // AMD
    define( 'fizzy-ui-utils/utils',[
      'desandro-matches-selector/matches-selector'
    ], function( matchesSelector ) {
      return factory( window, matchesSelector );
    });
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS
    module.exports = factory(
      window,
      require('desandro-matches-selector')
    );
  } else {
    // browser global
    window.fizzyUIUtils = factory(
      window,
      window.matchesSelector
    );
  }

}( window, function factory( window, matchesSelector ) {



var utils = {};

// ----- extend ----- //

// extends objects
utils.extend = function( a, b ) {
  for ( var prop in b ) {
    a[ prop ] = b[ prop ];
  }
  return a;
};

// ----- modulo ----- //

utils.modulo = function( num, div ) {
  return ( ( num % div ) + div ) % div;
};

// ----- makeArray ----- //

// turn element or nodeList into an array
utils.makeArray = function( obj ) {
  var ary = [];
  if ( Array.isArray( obj ) ) {
    // use object if already an array
    ary = obj;
  } else if ( obj && typeof obj == 'object' &&
    typeof obj.length == 'number' ) {
    // convert nodeList to array
    for ( var i=0; i < obj.length; i++ ) {
      ary.push( obj[i] );
    }
  } else {
    // array of single index
    ary.push( obj );
  }
  return ary;
};

// ----- removeFrom ----- //

utils.removeFrom = function( ary, obj ) {
  var index = ary.indexOf( obj );
  if ( index != -1 ) {
    ary.splice( index, 1 );
  }
};

// ----- getParent ----- //

utils.getParent = function( elem, selector ) {
  while ( elem.parentNode && elem != document.body ) {
    elem = elem.parentNode;
    if ( matchesSelector( elem, selector ) ) {
      return elem;
    }
  }
};

// ----- getQueryElement ----- //

// use element as selector string
utils.getQueryElement = function( elem ) {
  if ( typeof elem == 'string' ) {
    return document.querySelector( elem );
  }
  return elem;
};

// ----- handleEvent ----- //

// enable .ontype to trigger from .addEventListener( elem, 'type' )
utils.handleEvent = function( event ) {
  var method = 'on' + event.type;
  if ( this[ method ] ) {
    this[ method ]( event );
  }
};

// ----- filterFindElements ----- //

utils.filterFindElements = function( elems, selector ) {
  // make array of elems
  elems = utils.makeArray( elems );
  var ffElems = [];

  elems.forEach( function( elem ) {
    // check that elem is an actual element
    if ( !( elem instanceof HTMLElement ) ) {
      return;
    }
    // add elem if no selector
    if ( !selector ) {
      ffElems.push( elem );
      return;
    }
    // filter & find items if we have a selector
    // filter
    if ( matchesSelector( elem, selector ) ) {
      ffElems.push( elem );
    }
    // find children
    var childElems = elem.querySelectorAll( selector );
    // concat childElems to filterFound array
    for ( var i=0; i < childElems.length; i++ ) {
      ffElems.push( childElems[i] );
    }
  });

  return ffElems;
};

// ----- debounceMethod ----- //

utils.debounceMethod = function( _class, methodName, threshold ) {
  // original method
  var method = _class.prototype[ methodName ];
  var timeoutName = methodName + 'Timeout';

  _class.prototype[ methodName ] = function() {
    var timeout = this[ timeoutName ];
    if ( timeout ) {
      clearTimeout( timeout );
    }
    var args = arguments;

    var _this = this;
    this[ timeoutName ] = setTimeout( function() {
      method.apply( _this, args );
      delete _this[ timeoutName ];
    }, threshold || 100 );
  };
};

// ----- docReady ----- //

utils.docReady = function( callback ) {
  var readyState = document.readyState;
  if ( readyState == 'complete' || readyState == 'interactive' ) {
    // do async to allow for other scripts to run. metafizzy/flickity#441
    setTimeout( callback );
  } else {
    document.addEventListener( 'DOMContentLoaded', callback );
  }
};

// ----- htmlInit ----- //

// http://jamesroberts.name/blog/2010/02/22/string-functions-for-javascript-trim-to-camel-case-to-dashed-and-to-underscore/
utils.toDashed = function( str ) {
  return str.replace( /(.)([A-Z])/g, function( match, $1, $2 ) {
    return $1 + '-' + $2;
  }).toLowerCase();
};

var console = window.console;
/**
 * allow user to initialize classes via [data-namespace] or .js-namespace class
 * htmlInit( Widget, 'widgetName' )
 * options are parsed from data-namespace-options
 */
utils.htmlInit = function( WidgetClass, namespace ) {
  utils.docReady( function() {
    var dashedNamespace = utils.toDashed( namespace );
    var dataAttr = 'data-' + dashedNamespace;
    var dataAttrElems = document.querySelectorAll( '[' + dataAttr + ']' );
    var jsDashElems = document.querySelectorAll( '.js-' + dashedNamespace );
    var elems = utils.makeArray( dataAttrElems )
      .concat( utils.makeArray( jsDashElems ) );
    var dataOptionsAttr = dataAttr + '-options';
    var jQuery = window.jQuery;

    elems.forEach( function( elem ) {
      var attr = elem.getAttribute( dataAttr ) ||
        elem.getAttribute( dataOptionsAttr );
      var options;
      try {
        options = attr && JSON.parse( attr );
      } catch ( error ) {
        // log error, do not initialize
        if ( console ) {
          console.error( 'Error parsing ' + dataAttr + ' on ' + elem.className +
          ': ' + error );
        }
        return;
      }
      // initialize
      var instance = new WidgetClass( elem, options );
      // make available via $().data('namespace')
      if ( jQuery ) {
        jQuery.data( elem, namespace, instance );
      }
    });

  });
};

// -----  ----- //

return utils;

}));

// Flickity.Cell
( function( window, factory ) {
  // universal module definition
  /* jshint strict: false */
  if ( typeof define == 'function' && define.amd ) {
    // AMD
    define( 'flickity/js/cell',[
      'get-size/get-size'
    ], function( getSize ) {
      return factory( window, getSize );
    });
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS
    module.exports = factory(
      window,
      require('get-size')
    );
  } else {
    // browser global
    window.Flickity = window.Flickity || {};
    window.Flickity.Cell = factory(
      window,
      window.getSize
    );
  }

}( window, function factory( window, getSize ) {



function Cell( elem, parent ) {
  this.element = elem;
  this.parent = parent;

  this.create();
}

var proto = Cell.prototype;

proto.create = function() {
  this.element.style.position = 'absolute';
  this.x = 0;
  this.shift = 0;
};

proto.destroy = function() {
  // reset style
  this.element.style.position = '';
  var side = this.parent.originSide;
  this.element.style[ side ] = '';
};

proto.getSize = function() {
  this.size = getSize( this.element );
};

proto.setPosition = function( x ) {
  this.x = x;
  this.updateTarget();
  this.renderPosition( x );
};

// setDefaultTarget v1 method, backwards compatibility, remove in v3
proto.updateTarget = proto.setDefaultTarget = function() {
  var marginProperty = this.parent.originSide == 'left' ? 'marginLeft' : 'marginRight';
  this.target = this.x + this.size[ marginProperty ] +
    this.size.width * this.parent.cellAlign;
};

proto.renderPosition = function( x ) {
  // render position of cell with in slider
  var side = this.parent.originSide;
  this.element.style[ side ] = this.parent.getPositionValue( x );
};

/**
 * @param {Integer} factor - 0, 1, or -1
**/
proto.wrapShift = function( shift ) {
  this.shift = shift;
  this.renderPosition( this.x + this.parent.slideableWidth * shift );
};

proto.remove = function() {
  this.element.parentNode.removeChild( this.element );
};

return Cell;

}));

// slide
( function( window, factory ) {
  // universal module definition
  /* jshint strict: false */
  if ( typeof define == 'function' && define.amd ) {
    // AMD
    define( 'flickity/js/slide',factory );
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS
    module.exports = factory();
  } else {
    // browser global
    window.Flickity = window.Flickity || {};
    window.Flickity.Slide = factory();
  }

}( window, function factory() {
'use strict';

function Slide( parent ) {
  this.parent = parent;
  this.isOriginLeft = parent.originSide == 'left';
  this.cells = [];
  this.outerWidth = 0;
  this.height = 0;
}

var proto = Slide.prototype;

proto.addCell = function( cell ) {
  this.cells.push( cell );
  this.outerWidth += cell.size.outerWidth;
  this.height = Math.max( cell.size.outerHeight, this.height );
  // first cell stuff
  if ( this.cells.length == 1 ) {
    this.x = cell.x; // x comes from first cell
    var beginMargin = this.isOriginLeft ? 'marginLeft' : 'marginRight';
    this.firstMargin = cell.size[ beginMargin ];
  }
};

proto.updateTarget = function() {
  var endMargin = this.isOriginLeft ? 'marginRight' : 'marginLeft';
  var lastCell = this.getLastCell();
  var lastMargin = lastCell ? lastCell.size[ endMargin ] : 0;
  var slideWidth = this.outerWidth - ( this.firstMargin + lastMargin );
  this.target = this.x + this.firstMargin + slideWidth * this.parent.cellAlign;
};

proto.getLastCell = function() {
  return this.cells[ this.cells.length - 1 ];
};

proto.select = function() {
  this.changeSelectedClass('add');
};

proto.unselect = function() {
  this.changeSelectedClass('remove');
};

proto.changeSelectedClass = function( method ) {
  this.cells.forEach( function( cell ) {
    cell.element.classList[ method ]('is-selected');
  });
};

proto.getCellElements = function() {
  return this.cells.map( function( cell ) {
    return cell.element;
  });
};

return Slide;

}));

// animate
( function( window, factory ) {
  // universal module definition
  /* jshint strict: false */
  if ( typeof define == 'function' && define.amd ) {
    // AMD
    define( 'flickity/js/animate',[
      'fizzy-ui-utils/utils'
    ], function( utils ) {
      return factory( window, utils );
    });
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS
    module.exports = factory(
      window,
      require('fizzy-ui-utils')
    );
  } else {
    // browser global
    window.Flickity = window.Flickity || {};
    window.Flickity.animatePrototype = factory(
      window,
      window.fizzyUIUtils
    );
  }

}( window, function factory( window, utils ) {



// -------------------------- requestAnimationFrame -------------------------- //

// get rAF, prefixed, if present
var requestAnimationFrame = window.requestAnimationFrame ||
  window.webkitRequestAnimationFrame;

// fallback to setTimeout
var lastTime = 0;
if ( !requestAnimationFrame )  {
  requestAnimationFrame = function( callback ) {
    var currTime = new Date().getTime();
    var timeToCall = Math.max( 0, 16 - ( currTime - lastTime ) );
    var id = setTimeout( callback, timeToCall );
    lastTime = currTime + timeToCall;
    return id;
  };
}

// -------------------------- animate -------------------------- //

var proto = {};

proto.startAnimation = function() {
  if ( this.isAnimating ) {
    return;
  }

  this.isAnimating = true;
  this.restingFrames = 0;
  this.animate();
};

proto.animate = function() {
  this.applyDragForce();
  this.applySelectedAttraction();

  var previousX = this.x;

  this.integratePhysics();
  this.positionSlider();
  this.settle( previousX );
  // animate next frame
  if ( this.isAnimating ) {
    var _this = this;
    requestAnimationFrame( function animateFrame() {
      _this.animate();
    });
  }
};


var transformProperty = ( function () {
  var style = document.documentElement.style;
  if ( typeof style.transform == 'string' ) {
    return 'transform';
  }
  return 'WebkitTransform';
})();

proto.positionSlider = function() {
  var x = this.x;
  // wrap position around
  if ( this.options.wrapAround && this.cells.length > 1 ) {
    x = utils.modulo( x, this.slideableWidth );
    x = x - this.slideableWidth;
    this.shiftWrapCells( x );
  }

  x = x + this.cursorPosition;
  // reverse if right-to-left and using transform
  x = this.options.rightToLeft && transformProperty ? -x : x;
  var value = this.getPositionValue( x );
  // use 3D tranforms for hardware acceleration on iOS
  // but use 2D when settled, for better font-rendering
  this.slider.style[ transformProperty ] = this.isAnimating ?
    'translate3d(' + value + ',0,0)' : 'translateX(' + value + ')';

  // scroll event
  var firstSlide = this.slides[0];
  if ( firstSlide ) {
    var positionX = -this.x - firstSlide.target;
    var progress = positionX / this.slidesWidth;
    this.dispatchEvent( 'scroll', null, [ progress, positionX ] );
  }
};

proto.positionSliderAtSelected = function() {
  if ( !this.cells.length ) {
    return;
  }
  this.x = -this.selectedSlide.target;
  this.positionSlider();
};

proto.getPositionValue = function( position ) {
  if ( this.options.percentPosition ) {
    // percent position, round to 2 digits, like 12.34%
    return ( Math.round( ( position / this.size.innerWidth ) * 10000 ) * 0.01 )+ '%';
  } else {
    // pixel positioning
    return Math.round( position ) + 'px';
  }
};

proto.settle = function( previousX ) {
  // keep track of frames where x hasn't moved
  if ( !this.isPointerDown && Math.round( this.x * 100 ) == Math.round( previousX * 100 ) ) {
    this.restingFrames++;
  }
  // stop animating if resting for 3 or more frames
  if ( this.restingFrames > 2 ) {
    this.isAnimating = false;
    delete this.isFreeScrolling;
    // render position with translateX when settled
    this.positionSlider();
    this.dispatchEvent('settle');
  }
};

proto.shiftWrapCells = function( x ) {
  // shift before cells
  var beforeGap = this.cursorPosition + x;
  this._shiftCells( this.beforeShiftCells, beforeGap, -1 );
  // shift after cells
  var afterGap = this.size.innerWidth - ( x + this.slideableWidth + this.cursorPosition );
  this._shiftCells( this.afterShiftCells, afterGap, 1 );
};

proto._shiftCells = function( cells, gap, shift ) {
  for ( var i=0; i < cells.length; i++ ) {
    var cell = cells[i];
    var cellShift = gap > 0 ? shift : 0;
    cell.wrapShift( cellShift );
    gap -= cell.size.outerWidth;
  }
};

proto._unshiftCells = function( cells ) {
  if ( !cells || !cells.length ) {
    return;
  }
  for ( var i=0; i < cells.length; i++ ) {
    cells[i].wrapShift( 0 );
  }
};

// -------------------------- physics -------------------------- //

proto.integratePhysics = function() {
  this.x += this.velocity;
  this.velocity *= this.getFrictionFactor();
};

proto.applyForce = function( force ) {
  this.velocity += force;
};

proto.getFrictionFactor = function() {
  return 1 - this.options[ this.isFreeScrolling ? 'freeScrollFriction' : 'friction' ];
};

proto.getRestingPosition = function() {
  // my thanks to Steven Wittens, who simplified this math greatly
  return this.x + this.velocity / ( 1 - this.getFrictionFactor() );
};

proto.applyDragForce = function() {
  if ( !this.isPointerDown ) {
    return;
  }
  // change the position to drag position by applying force
  var dragVelocity = this.dragX - this.x;
  var dragForce = dragVelocity - this.velocity;
  this.applyForce( dragForce );
};

proto.applySelectedAttraction = function() {
  // do not attract if pointer down or no cells
  if ( this.isPointerDown || this.isFreeScrolling || !this.cells.length ) {
    return;
  }
  var distance = this.selectedSlide.target * -1 - this.x;
  var force = distance * this.options.selectedAttraction;
  this.applyForce( force );
};

return proto;

}));

// Flickity main
( function( window, factory ) {
  // universal module definition
  /* jshint strict: false */
  if ( typeof define == 'function' && define.amd ) {
    // AMD
    define( 'flickity/js/flickity',[
      'ev-emitter/ev-emitter',
      'get-size/get-size',
      'fizzy-ui-utils/utils',
      './cell',
      './slide',
      './animate'
    ], function( EvEmitter, getSize, utils, Cell, Slide, animatePrototype ) {
      return factory( window, EvEmitter, getSize, utils, Cell, Slide, animatePrototype );
    });
  } else if ( typeof module == 'object' && module.exports ) {
    // CommonJS
    module.exports = factory(
      window,
      require('ev-emitter'),
      require('get-size'),
      require('fizzy-ui-utils'),
      require('./cell'),
      require('./slide'),
      require('./animate')
    );
  } else {
    // browser global
    var _Flickity = window.Flickity;

    window.Flickity = factory(
      window,
      window.EvEmitter,
      window.getSize,
      window.fizzyUIUtils,
      _Flickity.Cell,
      _Flickity.Slide,
      _Flickity.animatePrototype
    );
  }

}( window, function factory( window, EvEmitter, getSize,
  utils, Cell, Slide, animatePrototype ) {



// vars
var jQuery = window.jQuery;
var getComputedStyle = window.getComputedStyle;
var console = window.console;

function moveElements( elems, toElem ) {
  elems = utils.makeArray( elems );
  while ( elems.length ) {
    toElem.appendChild( elems.shift() );
  }
}

// -------------------------- Flickity -------------------------- //

// globally unique identifiers
var GUID = 0;
// internal store of all Flickity intances
var instances = {};

function Flickity( element, options ) {
  var queryElement = utils.getQueryElement( element );
  if ( !queryElement ) {
    if ( console ) {
      console.error( 'Bad element for Flickity: ' + ( queryElement || element ) );
    }
    return;
  }
  this.element = queryElement;
  // do not initialize twice on same element
  if ( this.element.flickityGUID ) {
    var instance = instances[ this.element.flickityGUID ];
    instance.option( options );
    return instance;
  }

  // add jQuery
  if ( jQuery ) {
    this.$element = jQuery( this.element );
  }
  // options
  this.options = utils.extend( {}, this.constructor.defaults );
  this.option( options );

  // kick things off
  this._create();
}

Flickity.defaults = {
  accessibility: true,
  // adaptiveHeight: false,
  cellAlign: 'center',
  // cellSelector: undefined,
  // contain: false,
  freeScrollFriction: 0.075, // friction when free-scrolling
  friction: 0.28, // friction when selecting
  namespaceJQueryEvents: true,
  // initialIndex: 0,
  percentPosition: true,
  resize: true,
  selectedAttraction: 0.025,
  setGallerySize: true
  // watchCSS: false,
  // wrapAround: false
};

// hash of methods triggered on _create()
Flickity.createMethods = [];

var proto = Flickity.prototype;
// inherit EventEmitter
utils.extend( proto, EvEmitter.prototype );

proto._create = function() {
  // add id for Flickity.data
  var id = this.guid = ++GUID;
  this.element.flickityGUID = id; // expando
  instances[ id ] = this; // associate via id
  // initial properties
  this.selectedIndex = 0;
  // how many frames slider has been in same position
  this.restingFrames = 0;
  // initial physics properties
  this.x = 0;
  this.velocity = 0;
  this.originSide = this.options.rightToLeft ? 'right' : 'left';
  // create viewport & slider
  this.viewport = document.createElement('div');
  this.viewport.className = 'flickity-viewport';
  this._createSlider();

  if ( this.options.resize || this.options.watchCSS ) {
    window.addEventListener( 'resize', this );
  }

  Flickity.createMethods.forEach( function( method ) {
    this[ method ]();
  }, this );

  if ( this.options.watchCSS ) {
    this.watchCSS();
  } else {
    this.activate();
  }

};

/**
 * set options
 * @param {Object} opts
 */
proto.option = function( opts ) {
  utils.extend( this.options, opts );
};

proto.activate = function() {
  if ( this.isActive ) {
    return;
  }
  this.isActive = true;
  this.element.classList.add('flickity-enabled');
  if ( this.options.rightToLeft ) {
    this.element.classList.add('flickity-rtl');
  }

  this.getSize();
  // move initial cell elements so they can be loaded as cells
  var cellElems = this._filterFindCellElements( this.element.children );
  moveElements( cellElems, this.slider );
  this.viewport.appendChild( this.slider );
  this.element.appendChild( this.viewport );
  // get cells from children
  this.reloadCells();

  if ( this.options.accessibility ) {
    // allow element to focusable
    this.element.tabIndex = 0;
    // listen for key presses
    this.element.addEventListener( 'keydown', this );
  }

  this.emitEvent('activate');

  var index;
  var initialIndex = this.options.initialIndex;
  if ( this.isInitActivated ) {
    index = this.selectedIndex;
  } else if ( initialIndex !== undefined ) {
    index = this.cells[ initialIndex ] ? initialIndex : 0;
  } else {
    index = 0;
  }
  // select instantly
  this.select( index, false, true );
  // flag for initial activation, for using initialIndex
  this.isInitActivated = true;
};

// slider positions the cells
proto._createSlider = function() {
  // slider element does all the positioning
  var slider = document.createElement('div');
  slider.className = 'flickity-slider';
  slider.style[ this.originSide ] = 0;
  this.slider = slider;
};

proto._filterFindCellElements = function( elems ) {
  return utils.filterFindElements( elems, this.options.cellSelector );
};

// goes through all children
proto.reloadCells = function() {
  // collection of item elements
  this.cells = this._makeCells( this.slider.children );
  this.positionCells();
  this._getWrapShiftCells();
  this.setGallerySize();
};

/**
 * turn elements into Flickity.Cells
 * @param {Array or NodeList or HTMLElement} elems
 * @returns {Array} items - collection of new Flickity Cells
 */
proto._makeCells = function( elems ) {
  var cellElems = this._filterFindCellElements( elems );

  // create new Flickity for collection
  var cells = cellElems.map( function( cellElem ) {
    return new Cell( cellElem, this );
  }, this );

  return cells;
};

proto.getLastCell = function() {
  return this.cells[ this.cells.length - 1 ];
};

proto.getLastSlide = function() {
  return this.slides[ this.slides.length - 1 ];
};

// positions all cells
proto.positionCells = function() {
  // size all cells
  this._sizeCells( this.cells );
  // position all cells
  this._positionCells( 0 );
};

/**
 * position certain cells
 * @param {Integer} index - which cell to start with
 */
proto._positionCells = function( index ) {
  index = index || 0;
  // also measure maxCellHeight
  // start 0 if positioning all cells
  this.maxCellHeight = index ? this.maxCellHeight || 0 : 0;
  var cellX = 0;
  // get cellX
  if ( index > 0 ) {
    var startCell = this.cells[ index - 1 ];
    cellX = startCell.x + startCell.size.outerWidth;
  }
  var len = this.cells.length;
  for ( var i=index; i < len; i++ ) {
    var cell = this.cells[i];
    cell.setPosition( cellX );
    cellX += cell.size.outerWidth;
    this.maxCellHeight = Math.max( cell.size.outerHeight, this.maxCellHeight );
  }
  // keep track of cellX for wrap-around
  this.slideableWidth = cellX;
  // slides
  this.updateSlides();
  // contain slides target
  this._containSlides();
  // update slidesWidth
  this.slidesWidth = len ? this.getLastSlide().target - this.slides[0].target : 0;
};

/**
 * cell.getSize() on multiple cells
 * @param {Array} cells
 */
proto._sizeCells = function( cells ) {
  cells.forEach( function( cell ) {
    cell.getSize();
  });
};

// --------------------------  -------------------------- //

proto.updateSlides = function() {
  this.slides = [];
  if ( !this.cells.length ) {
    return;
  }

  var slide = new Slide( this );
  this.slides.push( slide );
  var isOriginLeft = this.originSide == 'left';
  var nextMargin = isOriginLeft ? 'marginRight' : 'marginLeft';

  var canCellFit = this._getCanCellFit();

  this.cells.forEach( function( cell, i ) {
    // just add cell if first cell in slide
    if ( !slide.cells.length ) {
      slide.addCell( cell );
      return;
    }

    var slideWidth = ( slide.outerWidth - slide.firstMargin ) +
      ( cell.size.outerWidth - cell.size[ nextMargin ] );

    if ( canCellFit.call( this, i, slideWidth ) ) {
      slide.addCell( cell );
    } else {
      // doesn't fit, new slide
      slide.updateTarget();

      slide = new Slide( this );
      this.slides.push( slide );
      slide.addCell( cell );
    }
  }, this );
  // last slide
  slide.updateTarget();
  // update .selectedSlide
  this.updateSelectedSlide();
};

proto._getCanCellFit = function() {
  var groupCells = this.options.groupCells;
  if ( !groupCells ) {
    return function() {
      return false;
    };
  } else if ( typeof groupCells == 'number' ) {
    // group by number. 3 -> [0,1,2], [3,4,5], ...
    var number = parseInt( groupCells, 10 );
    return function( i ) {
      return ( i % number ) !== 0;
    };
  }
  // default, group by width of slide
  // parse '75%
  var percentMatch = typeof groupCells == 'string' &&
    groupCells.match(/^(\d+)%$/);
  var percent = percentMatch ? parseInt( percentMatch[1], 10 ) / 100 : 1;
  return function( i, slideWidth ) {
    return slideWidth <= ( this.size.innerWidth + 1 ) * percent;
  };
};

// alias _init for jQuery plugin .flickity()
proto._init =
proto.reposition = function() {
  this.positionCells();
  this.positionSliderAtSelected();
};

proto.getSize = function() {
  this.size = getSize( this.element );
  this.setCellAlign();
  this.cursorPosition = this.size.innerWidth * this.cellAlign;
};

var cellAlignShorthands = {
  // cell align, then based on origin side
  center: {
    left: 0.5,
    right: 0.5
  },
  left: {
    left: 0,
    right: 1
  },
  right: {
    right: 0,
    left: 1
  }
};

proto.setCellAlign = function() {
  var shorthand = cellAlignShorthands[ this.options.cellAlign ];
  this.cellAlign = shorthand ? shorthand[ this.originSide ] : this.options.cellAlign;
};

proto.setGallerySize = function() {
  if ( this.options.setGallerySize ) {
    var height = this.options.adaptiveHeight && this.selectedSlide ?
      this.selectedSlide.height : this.maxCellHeight;
    this.viewport.style.height = height + 'px';
  }
};

proto._getWrapShiftCells = function() {
  // only for wrap-around
  if ( !this.options.wrapAround ) {
    return;
  }
  // unshift previous cells
  this._unshiftCells( this.beforeShiftCells );
  this._unshiftCells( this.afterShiftCells );
  // get before cells
  // initial gap
  var gapX = this.cursorPosition;
  var cellIndex = this.cells.length - 1;
  this.beforeShiftCells = this._getGapCells( gapX, cellIndex, -1 );
  // get after cells
  // ending gap between last cell and end of gallery viewport
  gapX = this.size.innerWidth - this.cursorPosition;
  // start cloning at first cell, working forwards
  this.afterShiftCells = this._getGapCells( gapX, 0, 1 );
};

proto._getGapCells = function( gapX, cellIndex, increment ) {
  // keep adding cells until the cover the initial gap
  var cells = [];
  while ( gapX > 0 ) {
    var cell = this.cells[ cellIndex ];
    if ( !cell ) {
      break;
    }
    cells.push( cell );
    cellIndex += increment;
    gapX -= cell.size.outerWidth;
  }
  return cells;
};

// ----- contain ----- //

// contain cell targets so no excess sliding
proto._containSlides = function() {
  if ( !this.options.contain || this.options.wrapAround || !this.cells.length ) {
    return;
  }
  var isRightToLeft = this.options.rightToLeft;
  var beginMargin = isRightToLeft ? 'marginRight' : 'marginLeft';
  var endMargin = isRightToLeft ? 'marginLeft' : 'marginRight';
  var contentWidth = this.slideableWidth - this.getLastCell().size[ endMargin ];
  // content is less than gallery size
  var isContentSmaller = contentWidth < this.size.innerWidth;
  // bounds
  var beginBound = this.cursorPosition + this.cells[0].size[ beginMargin ];
  var endBound = contentWidth - this.size.innerWidth * ( 1 - this.cellAlign );
  // contain each cell target
  this.slides.forEach( function( slide ) {
    if ( isContentSmaller ) {
      // all cells fit inside gallery
      slide.target = contentWidth * this.cellAlign;
    } else {
      // contain to bounds
      slide.target = Math.max( slide.target, beginBound );
      slide.target = Math.min( slide.target, endBound );
    }
  }, this );
};

// -----  ----- //

/**
 * emits events via eventEmitter and jQuery events
 * @param {String} type - name of event
 * @param {Event} event - original event
 * @param {Array} args - extra arguments
 */
proto.dispatchEvent = function( type, event, args ) {
  var emitArgs = event ? [ event ].concat( args ) : args;
  this.emitEvent( type, emitArgs );

  if ( jQuery && this.$element ) {
    // default trigger with type if no event
    type += this.options.namespaceJQueryEvents ? '.flickity' : '';
    var $event = type;
    if ( event ) {
      // create jQuery event
      var jQEvent = jQuery.Event( event );
      jQEvent.type = type;
      $event = jQEvent;
    }
    this.$element.trigger( $event, args );
  }
};

// -------------------------- select -------------------------- //

/**
 * @param {Integer} index - index of the slide
 * @param {Boolean} isWrap - will wrap-around to last/first if at the end
 * @param {Boolean} isInstant - will immediately set position at selected cell
 */
proto.select = function( index, isWrap, isInstant ) {
  if ( !this.isActive ) {
    return;
  }
  index = parseInt( index, 10 );
  this._wrapSelect( index );

  if ( this.options.wrapAround || isWrap ) {
    index = utils.modulo( index, this.slides.length );
  }
  // bail if invalid index
  if ( !this.slides[ index ] ) {
    return;
  }
  this.selectedIndex = index;
  this.updateSelectedSlide();
  if ( isInstant ) {
    this.positionSliderAtSelected();
  } else {
    this.startAnimation();
  }
  if ( this.options.adaptiveHeight ) {
    this.setGallerySize();
  }

  this.dispatchEvent('select');
  // old v1 event name, remove in v3
  this.dispatchEvent('cellSelect');
};

// wraps position for wrapAround, to move to closest slide. #113
proto._wrapSelect = function( index ) {
  var len = this.slides.length;
  var isWrapping = this.options.wrapAround && len > 1;
  if ( !isWrapping ) {
    return index;
  }
  var wrapIndex = utils.modulo( index, len );
  // go to shortest
  var delta = Math.abs( wrapIndex - this.selectedIndex );
  var backWrapDelta = Math.abs( ( wrapIndex + len ) - this.selectedIndex );
  var forewardWrapDelta = Math.abs( ( wrapIndex - len ) - this.selectedIndex );
  if ( !this.isDragSelect && backWrapDelta < delta ) {
    index += len;
  } else if ( !this.isDragSelect && forewardWrapDelta < delta ) {
    index -= len;
  }
  // wrap position so slider is within normal area
  if ( index < 0 ) {
    this.x -= this.slideableWidth;
  } else if ( index >= len ) {
    this.x += this.slideableWidth;
  }
};

proto.previous = function( isWrap, isInstant ) {
  this.select( this.selectedIndex - 1, isWrap, isInstant );
};

proto.next = function( isWrap, isInstant ) {
  this.select( this.selectedIndex + 1, isWrap, isInstant );
};

proto.updateSelectedSlide = function() {
  var slide = this.slides[ this.selectedIndex ];
  // selectedIndex could be outside of slides, if triggered before resize()
  if ( !slide ) {
    return;
  }
  // unselect previous selected slide
  this.unselectSelectedSlide();
  // update new selected slide
  this.selectedSlide = slide;
  slide.select();
  this.selectedCells = slide.cells;
  this.selectedElements = slide.getCellElements();
  // HACK: selectedCell & selectedElement is first cell in slide, backwards compatibility
  // Remove in v3?
  this.selectedCell = slide.cells[0];
  this.selectedElement = this.selectedElements[0];
};

proto.unselectSelectedSlide = function() {
  if ( this.selectedSlide ) {
    this.selectedSlide.unselect();
  }
};

/**
 * select slide from number or cell element
 * @param {Element or Number} elem
 */
proto.selectCell = function( value, isWrap, isInstant ) {
  // get cell
  var cell;
  if ( typeof value == 'number' ) {
    cell = this.cells[ value ];
  } else {
    // use string as selector
    if ( typeof value == 'string' ) {
      value = this.element.querySelector( value );
    }
    // get cell from element
    cell = this.getCell( value );
  }
  // select slide that has cell
  for ( var i=0; cell && i < this.slides.length; i++ ) {
    var slide = this.slides[i];
    var index = slide.cells.indexOf( cell );
    if ( index != -1 ) {
      this.select( i, isWrap, isInstant );
      return;
    }
  }
};

// -------------------------- get cells -------------------------- //

/**
 * get Flickity.Cell, given an Element
 * @param {Element} elem
 * @returns {Flickity.Cell} item
 */
proto.getCell = function( elem ) {
  // loop through cells to get the one that matches
  for ( var i=0; i < this.cells.length; i++ ) {
    var cell = this.cells[i];
    if ( cell.element == elem ) {
      return cell;
    }
  }
};

/**
 * get collection of Flickity.Cells, given Elements
 * @param {Element, Array, NodeList} elems
 * @returns {Array} cells - Flickity.Cells
 */
proto.getCells = function( elems ) {
  elems = utils.makeArray( elems );
  var cells = [];
  elems.forEach( function( elem ) {
    var cell = this.getCell( elem );
    if ( cell ) {
      cells.push( cell );
    }
  }, this );
  return cells;
};

/**
 * get cell elements
 * @returns {Array} cellElems
 */
proto.getCellElements = function() {
  return this.cells.map( function( cell ) {
    return cell.element;
  });
};

/**
 * get parent cell from an element
 * @param {Element} elem
 * @returns {Flickit.Cell} cell
 */
proto.getParentCell = function( elem ) {
  // first check if elem is cell
  var cell = this.getCell( elem );
  if ( cell ) {
    return cell;
  }
  // try to get parent cell elem
  elem = utils.getParent( elem, '.flickity-slider > *' );
  return this.getCell( elem );
};

/**
 * get cells adjacent to a slide
 * @param {Integer} adjCount - number of adjacent slides
 * @param {Integer} index - index of slide to start
 * @returns {Array} cells - array of Flickity.Cells
 */
proto.getAdjacentCellElements = function( adjCount, index ) {
  if ( !adjCount ) {
    return this.selectedSlide.getCellElements();
  }
  index = index === undefined ? this.selectedIndex : index;

  var len = this.slides.length;
  if ( 1 + ( adjCount * 2 ) >= len ) {
    return this.getCellElements();
  }

  var cellElems = [];
  for ( var i = index - adjCount; i <= index + adjCount ; i++ ) {
    var slideIndex = this.options.wrapAround ? utils.modulo( i, len ) : i;
    var slide = this.slides[ slideIndex ];
    if ( slide ) {
      cellElems = cellElems.concat( slide.getCellElements() );
    }
  }
  return cellElems;
};

// -------------------------- events -------------------------- //

proto.uiChange = function() {
  this.emitEvent('uiChange');
};

proto.childUIPointerDown = function( event ) {
  this.emitEvent( 'childUIPointerDown', [ event ] );
};

// ----- resize ----- //

proto.onresize = function() {
  this.watchCSS();
  this.resize();
};

utils.debounceMethod( Flickity, 'onresize', 150 );

proto.resize = function() {
  if ( !this.isActive ) {
    return;
  }
  this.getSize();
  // wrap values
  if ( this.options.wrapAround ) {
    this.x = utils.modulo( this.x, this.slideableWidth );
  }
  this.positionCells();
  this._getWrapShiftCells();
  this.setGallerySize();
  this.emitEvent('resize');
  // update selected index for group slides, instant
  // TODO: position can be lost between groups of various numbers
  var selectedElement = this.selectedElements && this.selectedElements[0];
  this.selectCell( selectedElement, false, true );
};

// watches the :after property, activates/deactivates
proto.watchCSS = function() {
  var watchOption = this.options.watchCSS;
  if ( !watchOption ) {
    return;
  }

  var afterContent = getComputedStyle( this.element, ':after' ).content;
  // activate if :after { content: 'flickity' }
  if ( afterContent.indexOf('flickity') != -1 ) {
    this.activate();
  } else {
    this.deactivate();
  }
};

// ----- keydown ----- //

// go previous/next if left/right keys pressed
proto.onkeydown = function( event ) {
  // only work if element is in focus
  if ( !this.options.accessibility ||
    ( document.activeElement && document.activeElement != this.element ) ) {
    return;
  }

  if ( event.keyCode == 37 ) {
    // go left
    var leftMethod = this.options.rightToLeft ? 'next' : 'previous';
    this.uiChange();
    this[ leftMethod ]();
  } else if ( event.keyCode == 39 ) {
    // go right
    var rightMethod = this.options.rightToLeft ? 'previous' : 'next';
    this.uiChange();
    this[ rightMethod ]();
  }
};

// -------------------------- destroy -------------------------- //

// deactivate all Flickity functionality, but keep stuff available
proto.deactivate = function()