垂直居中，对齐

单行文字-居中

<div>一行文字一行文字一行文字一行文字</div>

div {
  height:32px;
  line-height:32px;
}

 

多行文字-居中

<div class="parent">
    <p class="son">
         一行文字
         一行文字
         一行文字
    </p>
</div>

.parent {
           display: table;
           width: 100px;
           height: 100px;
           text-align: center;
       }
.son  {
           display: table-cell;
           height: 50px;
           vertical-align: middle;
       }

 

css3弹性盒子--完美居中

<div class="flex-container">
  <div class="flex-item">完美居中</div>
</div>

.flex-container {
    display: -webkit-flex;
    display: flex;
    width: 400px;
    height: 250px;
    background-color: yellow;
}
.flex-item {
    background-color: blue;
    width: 75px;
    height: 75px;
    margin: auto;
}

 

css3弹性盒子--对齐

.flex-container {
    display: -webkit-flex;
    display: flex;
    width: 400px;
    height: 250px;
    background-color: yellow;
}
.flex-item {
    background-color: blue;
    width: 75px;
    height: 75px;
    margin: 10px;
}

.flex-item:first-child {
    margin-right: auto;
}

<div class="flex-container">
  <div class="flex-item">flex item 1</div>
  <div class="flex-item">flex item 2</div>
  <div class="flex-item">flex item 3</div>  
</div>

 

 css3弹性盒子--flex:1用法

<ul>
      <li>
        <span class="number">1</span>
        <span class="name">张三</span>
        <span>88</span>
      </li>
     <li>
        <span class="number">2</span>
        <span class="name">李四</span>
        <span>77</span>
     </li>
     <li>
        <span class="number">3</span>
        <span class="name">王五</span>
        <span>66</span>
     </li>
</ul>

ul {
  list-style: none;
  padding: 0;
}
li {
    padding: 8px 0;
    display: -webkit-flex;
    display: flex;
  }
.number {
      display: inline-block;
      width: 20px;
      height: 20px;
      margin-right: 16px;
      font-weight: 600;
      font-size: 12px;
      line-height: 20px;
      text-align: center;
      background-color: #f5f5f5;
      border-radius: 50%;
 }
.name {
      -webkit-box-flex: 1;
      flex: 1;
      margin-right: 8px;
      overflow: hidden;
      white-space: nowrap;
      text-overflow: ellipsis;
 }

 

flex: flex-grow flex-shrink flex-basis|auto|initial|inherit;

默认flex属性是0 1 auto，【父控件有剩余控件也不放大，父控件空间不足按1缩小，保持本身的空间大小】

flex:1;的值是1 1 0%，【父控件有剩余空间1份放大，父控件空间不足按1缩小，自身的空间大小是0%】