// 头部滚动 (function(){ let $header = document.querySelector('.header'); document.addEventListener('scroll',function(){ let scrollTop = document.documentElement.scrollTop; let ratio = Math.min(scrollTop/1000,1); $header.style.background = 'rgba(255,255,255,'+(ratio*0.8)+')'; $header.style.boxShadow = '1px 1px 6px rgba(0,0,0,'+(ratio*0.1)+')'; }); })(); // 底部滚动 (function(){ let timer = null; let $gotop = document.querySelector('.mod-fixedbar .gotop'); $gotop.addEventListener('click',function(){ cancelAnimationFrame(timer); let scrollTop = document.body.scrollTop || document.documentElement.scrollTop; let move = scrollTop/18; timer = requestAnimationFrame(function fn(){ var oTop = document.body.scrollTop || document.documentElement.scrollTop; if(oTop > 0){ document.body.scrollTop = document.documentElement.scrollTop = oTop - move; timer = requestAnimationFrame(fn); }else{ cancelAnimationFrame(timer); } }); }); })();