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snow.js

/**
 * jquery.snow - jQuery Snow Effect Plugin
 *
 * Available under MIT licence
 *
 * @version 1 (21. Jan 2012)
 * @author Ivan Lazarevic
 * @requires jQuery
 * @see http://workshop.rs
 *
 * @params minSize - min size of snowflake, 10 by default
 * @params maxSize - max size of snowflake, 20 by default
 * @params newOn - frequency in ms of appearing of new snowflake, 500 by default
 * @params flakeColor - color of snowflake, #FFFFFF by default
 * @example $.fn.snow({ maxSize: 200, newOn: 1000 });
 */

(function($){$.fn.snow=function(options){var $flake=$('<div id="flake" />').css({'position':'absolute','top':'-50px'}).html('&#10052;'),documentHeight=$(document).height(),documentWidth=$(document).width(),defaults={minSize:10,maxSize:20,newOn:500,flakeColor:"#FFFFFF"},options=$.extend({},defaults,options);var interval=setInterval(function(){var startPositionLeft=Math.random()*documentWidth-100,startOpacity=0.5+Math.random(),sizeFlake=options.minSize+Math.random()*options.maxSize,endPositionTop=documentHeight-40,endPositionLeft=startPositionLeft-100+Math.random()*200,durationFall=documentHeight*10+Math.random()*5000;$flake.clone().appendTo('body').css({left:startPositionLeft,opacity:startOpacity,'font-size':sizeFlake,color:options.flakeColor}).animate({top:endPositionTop,left:endPositionLeft,opacity:0.2},durationFall,'linear',function(){$(this).remove()});},options.newOn);};})(jQuery);

jQuery(document).ready(function($) {
    $.fn.snow();
});