46 lines
1.3 KiB
JavaScript
46 lines
1.3 KiB
JavaScript
(function () {
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var scrollTopButtons = document.querySelectorAll(".home-mobile-footer-top");
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scrollTopButtons.forEach(function (button) {
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button.addEventListener("click", function () {
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window.scrollTo({ top: 0, behavior: "smooth" });
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});
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});
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// 页脚进入视口后，把悬浮按钮（下载 App / 回到顶部）顶到页脚上方，避免遮住页脚内容。
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var footers = document.querySelectorAll(".footer-box, .home-mobile-footer");
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if (!footers.length) return;
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var root = document.documentElement;
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var ticking = false;
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var lastLift = -1;
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function visibleFooter() {
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for (var i = 0; i < footers.length; i++) {
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if (footers[i].offsetHeight > 0) return footers[i];
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}
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return null;
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}
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function update() {
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ticking = false;
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var footer = visibleFooter();
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var lift = 0;
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if (footer) {
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var top = footer.getBoundingClientRect().top;
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lift = Math.max(0, Math.round((window.innerHeight || 0) - top));
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}
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if (lift === lastLift) return;
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lastLift = lift;
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root.style.setProperty("--footer-lift", lift + "px");
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}
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function schedule() {
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if (ticking) return;
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ticking = true;
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window.requestAnimationFrame(update);
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}
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window.addEventListener("scroll", schedule, { passive: true });
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window.addEventListener("resize", schedule);
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schedule();
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})();
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