Question

如何将您在此photo中看到的浮动元素居中？我想把它从网页的左边带到中间，但是把它放在页面的顶部？

以下是HTML的代码：

<html>
    <head>
        <title>Batch File Generator | Home</title>
    </head>
  <link href="style.css" rel="stylesheet" >
    <ul>
         <li><a>Home</a></li>
         <li><a>Download</a>
             <ul>
                 <li><a href="32-bit version.exe" download="download">32-bit version</a></li>
                 <li><a href="64-bit version.exe" download="download">64-bit version</a></li>
             </ul>
         </li>
         <li><a>Discussion</a>
             <ul>
                 <li><a>Community forums</li></a>
                 <li><a>Ask the developers</li></a>
             </ul>
         </li>
         <li><a>News</a></li>
    </ul>
</html>

以下是CSS的代码：

body{
    background: url("background.jpg") no-repeat;
    background-size: cover;
    font-family: Arial;
    color: white;
}
ul{
    margin: 0px;
    padding: 0px;
    list-style: none;
}
ul li {
    float: left;
    width: 200px;
    height: 40px;
    background-color: black;
    opacity: .8;
    line-height: 40px;
    text-align: center;
    font-size: 20px;
}
ul li a {
    text-decoration: none;
    color: white;
    display: block;
}
ul li a:hover {
    background-color: green;
}
ul li ul li {
    display: none;
}
ul li:hover ul li {
    display: block;
}

Answer 1

对于HTML代码，请使用：

  <div class="wrapper">

    <div class="middle-content">
      <ul>
     <li><a>Home</a></li>
     <li><a>Download</a>
         <ul>
             <li><a href="32-bit version.exe" download="download">32-bit version</a></li>
             <li><a href="64-bit version.exe" download="download">64-bit version</a></li>
         </ul>
     </li>
     <li><a>Discussion</a>
         <ul>
             <li><a>Community forums</a></li>
             <li><a>Ask the developers</a></li>
         </ul>
     </li>
     <li><a>News</a></li>
</ul>
    </div>

  </div>

对于css代码：

    html{
  height: 100%;
}
body{
    background: url("background.jpg") no-repeat;
    background-size: cover;
    font-family: Arial;
    color: white;
    height: 100%;
}
.wrapper{
  display: table;
  width: 100%;
  height: 100%;
}
.middle-content{
    display: table-cell;
    vertical-align:middle;
    width: 100%;
}
ul{
    margin: 0px;
    padding: 0px;
    list-style: none;
}
ul li {
    float: left;
    width: 200px;
    height: 40px;
    background-color: black;
    opacity: .8;
    line-height: 40px;
    text-align: center;
    font-size: 20px;
}
ul li a {
    text-decoration: none;
    color: white;
    display: block;
}
ul li a:hover {
    background-color: green;
}
ul li ul li {
    display: none;
}
ul li:hover ul li {
    display: block;
}

Answer 2

使用flexbox解决方案。

* {
  box-sizing: border-box;
}

html,
body,
ul {
  padding: 0;
  margin: 0;
}

nav {
  width: 100%;
  background-color: darkgray;
}

li {
  list-style: none;
  padding: 15px;
  border: thin solid lightgray;
  position: relative;
  background-color: white;
}

li>a {
  display: inline-block;
  text-decoration: none;
}

.main-menu {
  display: flex;
  justify-content: center;
}

.sub-menu {
  display: none;
  position: absolute;
  left: 0px;
  width: 100%;
  margin-top: 15px;
}

.main-menu li:hover {
  background-color: lightgreen;
}

.sub-menu li:hover {
  background-color: lightblue;
}
.main-menu li:hover>.sub-menu {
  display: block;
}

<nav>
  <ul class="main-menu">
    <li><a>Home</a></li>
    <li><a>Download</a>
      <ul class="sub-menu">
        <li><a href="32-bit version.exe" download="download">32-bit version</a></li>
        <li><a href="64-bit version.exe" download="download">64-bit version</a></li>
      </ul>
    </li>
    <li><a>Discussion</a>
      <ul class="sub-menu">
        <li><a href="#">Community forums</a></li>
        <li><a href="#">Ask the developers</a></li>
      </ul>
    </li>
    <li><a>News</a></li>
  </ul>
</nav>

如何在CSS中居浮动元素？

2 个答案: