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20 lines
611 B
JavaScript
20 lines
611 B
JavaScript
document.addEventListener('DOMContentLoaded', function() {
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var scrollBtn = document.createElement('div')
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scrollBtn.id = 'scroll-btn'
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document.body.append(scrollBtn)
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window.addEventListener('scroll', function() {
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var offset = window.document.documentElement.scrollTop;
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scrollBtn.style.display = offset >= 500 ? "block" : "none";
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})
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scrollBtn.addEventListener('click', function(e) {
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e.stopPropagation();
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var step = window.scrollY / 15;
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var hdl = setInterval(function() {
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window.scrollTo(0, window.scrollY - step);
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if(window.scrollY <= 0) {
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clearInterval(hdl)
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}
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}, 15)
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})
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}) |