window.onload = function() {

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        var hgt3 = $('#container');
        var bgt3 = $('#container .dopis3');

        var bgtHalfW3 = bgt3.width()/2;
        var bgtHalfH3 = bgt3.height()/2;

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            bgt3.show();
            var scrollLeftPos3 = $(window).scrollLeft();
            var scrollTopPos3 = $(window).scrollTop();
            var offsetLft3 = hgt3.offset().left;
            var offsetTp3 = hgt3.offset().top;
            var upX3 = event.clientX;
            var upY3 = event.clientY;
            bgt3.css({backgroundPosition : ''+(offsetLft3-upX3+bgtHalfW3-scrollLeftPos3)+'px '+(offsetTp3-upY3+bgtHalfH3-scrollTopPos3)+'px',top:''+(-offsetTp3+upY3-bgtHalfH3+scrollTopPos3)+'px',left:''+(-offsetLft3+upX3-bgtHalfW3+scrollLeftPos3)+'px'});
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        hgt3.mouseout(function(){
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};