37 lines
1.1 KiB
JavaScript
37 lines
1.1 KiB
JavaScript
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const scrollToTopBtn = document.querySelector(".lw-scroll-top-btn");
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if (scrollToTopBtn) {
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const totalPageHeight = document.body.scrollHeight;
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let currentPageHeight = window.scrollY;
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const rootElement = document.documentElement;
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const fadeScrollTopBtn = (total, current) => {
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if (total / 3 < current) {
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!scrollToTopBtn.classList.contains("lw-scroll-top-btn--active")
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? scrollToTopBtn.classList.add("lw-scroll-top-btn--active")
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: null;
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} else {
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scrollToTopBtn.classList.contains("lw-scroll-top-btn--active")
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? scrollToTopBtn.classList.remove("lw-scroll-top-btn--active")
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: null;
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}
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};
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fadeScrollTopBtn(totalPageHeight, currentPageHeight);
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const onScrollShowBtn = () => {
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fadeScrollTopBtn(totalPageHeight, window.scrollY);
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};
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window.addEventListener("scroll", onScrollShowBtn);
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function scrollToTop() {
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rootElement.scrollTo({
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top: 0,
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behavior: "smooth",
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});
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}
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scrollToTopBtn.addEventListener("click", scrollToTop);
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}
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