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HTML

CSS

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JavaScript

Babel includes JSX processing.

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HTML

              
                <div class="modal">
  <div class="modal-header">弹出窗标题</div>
  <div class="modal-body">在当今天移动设备横行天下的年代,给我们前端人员制作页面带来无尽的烦恼,具体原因,大家都懂的。那么这里我们来模拟一个情形。有一个弹出层,我不知道他的大小有多大,我想让他在各种设备中永远水平居中。在下面示例中,我们用一个Dive来当作是弹出窗吧(偷懒了,不想花太多时间去做这个弹出窗效果)。</div>
</div>
              
            
!

CSS

              
                *{
  margin: 0;
  padding:0;
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}
html,
body {
  height: 100%;
}

.modal {
  border: 1px solid #bbb;
  border-radius: 5px;
  box-shadow: 0 0 3px rgba(0,0,0,.5);
  
  position:absolute;
  top:50%;
  left: 50%;
  -webkit-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);
}
.modal-header {
  padding: 10px 20px;
  background: rgba(0,0,0,.25);
  color:#fff;
}
.modal-body{
  padding: 20px;
  background: #fff;
}
              
            
!

JS

              
                
              
            
!
999px

Console