window.onload = function() {

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    };

};

function backToTop() {

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        x1 = document.documentElement.scrollLeft || 0;
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        x2 = document.body.scrollLeft || 0;
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    x3 = window.scrollX || 0;
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    var x = Math.max( x1 , Math.max( x2 , x3 ) );
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    window.scrollTo( Math.floor( x / 2 ) , Math.floor( y / 2 ) );

    if( x > 0 || y > 0 ) {

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}