18 lines
645 B
JavaScript
18 lines
645 B
JavaScript
window.addEventListener('DOMContentLoaded', () => {
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const observer = new IntersectionObserver(entries => {
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entries.forEach(entry => {
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const id = entry.target.getAttribute('id');
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if (entry.intersectionRatio > 0) {
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document.querySelector(`#TableOfContents ul li a[href="#${id}"]`).classList.add('active');
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} else {
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document.querySelector(`#TableOfContents ul li a[href="#${id}"]`).classList.remove('active');
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}
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});
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});
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// Track all headers that have an `id` applied
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document.querySelectorAll('article h3[id], article h2[id]').forEach((section) => {
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observer.observe(section);
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});
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});
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