如何加个遮罩

2018-03-22 126 阅读1分钟

xxx::before {
  content: '';
  display: block;
  position: absolute;
  left: 0;//width:100%;
  right: 0;//height: 100%;
  top: 0;
  bottom: 0;
  background: rgba(255,255,255,0.4);
}