所以我按照本教程（http://medialoot.com/blog/how-to-create-a-responsive-navigation-menu-using-only-css/）编写了一个响应式菜单。但它不是100％宽，我似乎无法做到这一点。你能告诉我如何解决它吗？
这是代码： https://jsfiddle.net/oyx9r4kh/1/
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>CSS Only Navigation Menu</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="CSS-1.css">
</head>
<body>
<div class="nav">
<ul id="menu">
<li><a href="#">Home</a></li>
<li>
<a href="#">About ￬</a>
<ul class="hidden">
<li><a href="#">Who We Are</a></li>
<li><a href="#">What We Do</a></li>
</ul>
</li>
<li>
<a href="#">Portfolio ￬</a>
<ul class="hidden">
<li><a href="#">Photography</a></li>
<li><a href="#">Web & User Interface Design</a></li>
<li><a href="#">Illustration</a></li>
</ul>
</li>
<li><a href="#">News</a></li>
<li><a href="#">Contact</a></li>
</ul>
</div>
<div class="hero">
<img src="http://www.shawcontractgroup.com.au/wp-content/uploads/2013/08/environmental-certifications.jpg">
</div>
CSS：
body {
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
}
/*Strip the ul of padding and list styling*/
ul {
list-style-type:none;
margin:0;
padding:0;
position: absolute;
}
/*Create a horizontal list with spacing*/
.nav {
width: 100%;
display: block;
float: left;
clear: both;
background: #2f3036;
margin-top: 0;
margin-bottom: 0.5%;
}
.menu {
width: 100%;
}
li {
display:inline-block;
float: left;
margin-right: 1px;
}
/*Style for menu links*/
li a {
display:block;
width: 100%;
min-width:170px;
height: 50px;
text-align: center;
line-height: 50px;
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
color: #fff;
background: #2f3036;
text-decoration: none;
}
/*Hover state for top level links*/
li:hover a {
background: #19c589;
}
/*Style for dropdown links*/
li:hover ul a {
background: #f3f3f3;
color: #2f3036;
height: 40px;
line-height: 40px;
}
/*Hover state for dropdown links*/
li:hover ul a:hover {
background: #19c589;
color: #fff;
}
/*Hide dropdown links until they are needed*/
li ul {
display: none;
}
/*Make dropdown links vertical*/
li ul li {
display: block;
float: none;
opacity: 0.9;
}
/*Prevent text wrapping*/
li ul li a {
width: auto;
min-width: 170px;
padding: 0 20px;
}
/*Display the dropdown on hover*/
ul li a:hover + .hidden, .hidden:hover {
display: block;
}
.hero {
margin-top: 50px;
display: block;
clear: both;
float: left;
width: 100%;
}
.hero img {
float: left;
max-width: 100%;
height: auto;
}
答案 0 :(得分：0)
这是因为position:absolute;上有ul。这将它从.nav流中取出，使其高度为0.因此，您需要明确地给.nav一个高度，或者将ul设置为不同的位置类型。
答案 1 :(得分：0)
这是您的工作和清洁代码。导航位于中心位置，您可以全屏预览。
<强>解释
Position: absolute应该在您的下拉导航
无需一起使用display:inline-block和float。
始终清除最后一个浮动元素之后的浮动，以便父元素可以正确包装它。
将#menu ID设置为max-width并设置margin: auto
建议：您应该使用media-queries进行自适应导航。
body {
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
}
.clear {
clear: both
}
/*Strip the ul of padding and list styling*/
ul {
list-style-type: none;
margin: 0;
padding: 0;
}
/*Create a horizontal list with spacing*/
.nav-wrap {
background: #2f3036;
}
.nav {
width: 100%;
background: #2f3036;
margin-top: 0;
margin-bottom: 0.5%;
}
#menu {
max-width: 855px;
margin: auto;
}
li {
margin-right: 1px;
float: left;
}
/*Style for menu links*/
li a {
display: block;
min-width: 170px;
height: 50px;
text-align: center;
line-height: 50px;
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
color: #fff;
background: #2f3036;
text-decoration: none;
}
/*Hover state for top level links*/
li:hover a {
background: #19c589;
}
/*Style for dropdown links*/
li:hover ul a {
background: #f3f3f3;
color: #2f3036;
height: 40px;
line-height: 40px;
}
/*Hover state for dropdown links*/
li:hover ul a:hover {
background: #19c589;
color: #fff;
}
/*Hide dropdown links until they are needed*/
li ul {
display: none;
position: absolute;
}
/*Make dropdown links vertical*/
li ul li {
display: block;
float: none;
opacity: 0.9;
}
/*Prevent text wrapping*/
li ul li a {
width: auto;
min-width: 170px;
padding: 0 20px;
}
/*Display the dropdown on hover*/
ul li a:hover + .hidden,
.hidden:hover {
display: block;
}
.col {
float: left;
width: 30%;
height: auto;
margin: 1.5% 1.5%;
border-radius: 10px;
border: 1px solid #FFF;
}
.col img {
max-width: 100%;
height: auto;
}
.col p {
text-align: center;
margin: 10px;
text-shadow: 1px 1px #ffF;
}
div.col:hover {
background-color: #FFFDD6;
}<body>
<div class='nav-wrap'>
<div class="nav">
<ul id="menu">
<li><a href="#">Home</a>
</li>
<li>
<a href="#">About ￬</a>
<ul class="hidden">
<li><a href="#">Who We Are</a>
</li>
<li><a href="#">What We Do</a>
</li>
</ul>
</li>
<li>
<a href="#">Products ￬</a>
<ul class="hidden">
<li><a href="#">Compounds</a>
</li>
<li><a href="#">Oils</a>
</li>
<li><a href="#">Illustration</a>
</li>
</ul>
</li>
<li><a href="#">News</a>
</li>
<li><a href="#">Contact</a>
</li>
<div class='clear'></div>
</ul>
</div>
</div>
</body>
答案 2 :(得分：0)
您需要向CSS添加媒体调用，以便在较小的屏幕尺寸上更改ul格式。
/*Responsive Styles*/
@media screen and (max-width : 760px){
/*Make dropdown links appear inline*/
ul {
position: static;
}
/*Create vertical spacing*/
li {
margin-bottom: 1px;
}
/*Make all menu links full width*/
ul li, li a {
width: 100%;
}
}