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(function () { |
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'use strict'; |
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|
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// Staggered entrance animation for HowTo steps |
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if (!('IntersectionObserver' in window)) return; |
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|
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document.querySelectorAll('.bkbg-hs-steps').forEach(function (ol) { |
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var steps = ol.querySelectorAll('.bkbg-hs-step'); |
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if (!steps.length) return; |
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|
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// Mark each step for animation |
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steps.forEach(function (step) { |
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step.setAttribute('data-animate', ''); |
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}); |
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|
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var io = new IntersectionObserver(function (entries) { |
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entries.forEach(function (entry) { |
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if (!entry.isIntersecting) return; |
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var step = entry.target; |
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// Get the index to stagger |
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var idx = Array.prototype.indexOf.call(steps, step); |
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setTimeout(function () { |
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step.setAttribute('data-animate', 'in'); |
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}, idx * 100); |
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io.unobserve(step); |
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}); |
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}, { threshold: 0.15, rootMargin: '0px 0px -40px 0px' }); |
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|
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steps.forEach(function (step) { |
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io.observe(step); |
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}); |
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}); |
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})(); |
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