我正在尝试从"创建一个下拉菜单"但似乎有一些颜色无法给出一个适当的下拉框。在导航栏的"首页"旁边有一个红色块。按钮。当我把鼠标悬停在"关于我们"上时;按钮再次出现红色可见，因此没有对齐下拉菜单链接。谁能解释一下怎么去掉多余的颜色?下面是我的代码:
<html>
<head>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
</head>
<br>
<style>
* {box-sizing: border-box;}
body {
margin: 0;
font-family: TIMES ROMAN;
}
.topnav {
overflow: hidden;
background-color: #e9e9e9;
}
.topnav a {
float: left;
color: black;
text-align: center;
padding: 14px 16px;
text-decoration: none;
font-size: 17px;
}
.topnav a:hover {
background-color: #ddd;
color: black;
}
.topnav a.active {
background-color: #330000;
color: white;
}
.topnav .search-container {
float: right;
}
.topnav input[type=text] {
padding: 6px;
margin-top: 8px;
font-size: 17px;
border: none;
}
.topnav .search-container button {
float: right;
padding: 6px 10px;
margin-top: 8px;
margin-right: 16px;
background: #ddd;
font-size: 17px;
border: none;
cursor: pointer;
}
.topnav .search-container button:hover {
background: #ccc;
}
.dropdown {
float: left;
overflow: hidden;
}
.dropdown .dropbtn {
font-size: 16px;
border: none;
outline: none;
color: white;
padding: 14px 16px;
background-color: inherit;
font: inherit;
margin: 0;
}
.navbar a:hover, .dropdown:hover .dropbtn {
}
.dropdown-content {
display: none;
position: absolute;
width: 100%;
left: 0;
box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
z-index: 1;
}
.dropdown-content .header {
padding: 16px;
color: white;
}
.dropdown:hover .dropdown-content {
display: block;
}
.column a {
float: none;
color: black;
padding: 16px;
text-decoration: none;
display: block;
text-align: left;
}
/* Clear floats after the columns */
.row:after {
content: "";
display: table;
clear: both;
}
@media screen and (max-width: 600px) {
.topnav .search-container {
float: none;
}
.topnav a, .topnav input[type=text], .topnav .search-container button {
float: none;
display: block;
text-align: left;
width: 100%;
margin: 0;
padding: 14px;
}
.topnav input[type=text] {
border: 1px solid #ccc;
}
}
</style>
<body style="background-color:#C0C0C0">
<div class="topnav">
<img src="D1.jpg" height="70" width="120" align="left"><br>
<a href="#home">Home</a>
<div class="dropdown">
<button class="dropbtn"><a class="active">About us
<i class="fa fa-caret-down"></i>
</button>
<div class="dropdown-content">
<div class="header">
</div>
<div class="row">
<div class="column">
<a href="#">Who are we?</a>
<a href="#">What do we do</a>
<a href="#">Project aims/goals</a>
<a href="#">History</a>
</div>
</div>
</div>
</div>
<a href="#contact">Contact ✆</a>
<a href="#about">Gallery 📸</a>
<a href="#about">Our services</a>
<a href="#about">Policy</a>
<a href="#about">Sign Up</a>
<div class="search-container">
<form action="/action_page.php">
<input type="text" placeholder="Search.." name="search">
<button type="submit"><i class="fa fa-search"></i></button>
</form>
</div>
</body>
</html>您对css的编码方式与您对html结构的编码方式不同。
<a class="active"><button class="dropbtn">About us <i class="fa fa-caret-down"></i></button></a>
检查上面的行并将其替换到您的代码中。
将button元素包裹在a(锚)标签中。