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原文网址：CSS之布局系列--顶部导航栏二级菜单居中展示_IT利刃出鞘的博客-CSDN博客
简介
本文介绍CSS将顶部导航栏居中展示并支持二级菜单下拉展示的方法。
代码
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>知识星球</title><style>* {margin: 0;padding: 0;}.top-container {background-color: #406ff9;height: 60px;}.menu-container {text-align: center;}.logo-container {position: absolute;color: white;line-height: 58px;font-weight: bold;margin-left: 10px;}.logo {font-size: 20px;margin-left: 10px;}.first-menu-container {display: inline-block;list-style: none;}.first-menu {line-height: 60px;text-align: center;float: left;}.second-menu {float: none;background-color: #406ff9;}.second-menu a:hover {color: white;background-color: #0033fc;}.second-menu-container {position: absolute;list-style: none;display: none;}.first-menu:hover ul {display: block;}a {text-decoration: none;color: white;display: block;padding: 0 15px;white-space: nowrap;font-weight: bold;}a:hover {background-color: #0033fc;}</style>
</head>
<body>
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</body>
</html>测试
