export function mountToc() {
	const observer = new IntersectionObserver((entries) => {
		for (const entry of entries) {
			const id = entry.target.getAttribute("id");
			document
				.querySelector(`.o-toc__item[href="#${id}"]`)
				?.classList.toggle("is-selected", entry.intersectionRatio > 0);
		}
	});

	document.querySelectorAll("section[id]").forEach((section) => {
		observer.observe(section);
	});
}