.foot{width:100%; height:8em; background-color:#cc5536;}
const sections = document.querySelectorAll('h2[id]');
if (link.getAttribute('href').includes(current)) {
font-size: 1.75rem;
#新手指南百度搜索引擎优化教程2026年SEO核心指标优化全流程
background: linear-gradient(to bottom, #3b82f6, #2563eb);