image.png

    1. <div class="top">
    2.   <div class="mask"></div>
    3. </div>
    1. .top{
    2.   background-color:red;
    3.   height:200px;
    4.   width:400px
    6. }
    7. .mask {
    8.     height: 100%;
    9.     width: 100%;
    10.     background: -webkit-gradient(linear, 0 top, 0 bottom, from(rgba(255, 255, 255, 0)), to(#fff));
    11. }