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/* Scroll To Top — frontend */ |
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( function () { |
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function init() { |
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document.querySelectorAll('.bkstt-wrap[data-trigger]').forEach(function(wrap) { |
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if (wrap._bksttInit) return; |
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wrap._bksttInit = true; |
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|
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var btn = wrap.querySelector('.bkstt-btn'); |
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if (!btn) return; |
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|
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var trigger = parseInt(wrap.getAttribute('data-trigger'),10) || 400; |
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var smooth = wrap.getAttribute('data-smooth') !== '0'; |
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var ticking = false; |
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|
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function update() { |
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var scrollY = window.scrollY || window.pageYOffset; |
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if (scrollY > trigger) { |
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wrap.classList.add('bkstt-visible'); |
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} else { |
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wrap.classList.remove('bkstt-visible'); |
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} |
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ticking = false; |
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} |
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|
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window.addEventListener('scroll', function() { |
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if (!ticking) { |
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requestAnimationFrame(update); |
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ticking = true; |
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} |
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}, {passive:true}); |
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|
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btn.addEventListener('click', function() { |
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window.scrollTo({ top: 0, behavior: smooth ? 'smooth' : 'auto' }); |
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}); |
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|
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// Initial check |
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update(); |
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}); |
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} |
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|
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if (document.readyState === 'loading') { |
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document.addEventListener('DOMContentLoaded', init); |
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} else { |
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init(); |
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} |
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}() ); |
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|
