CSS实现高亮光弧效果

DOCTYPE html>
html lang="en">
head>
    meta charset="UTF-8">
    title>lighttitle>
    style>
        body{
            margin: 0;
        }
        a.floor{
            display: block;
            height: 475px;
        }
        a.floor:hover:before{
            -webkit-transition: left 1.5s;
            -moz-transition: left 1.5s;
            transition: left 1.5s;
            left: 920px;
        }
        a.floor:before{
            content: "";
            position: absolute;
            width: 80px;
            height: 475px;
            top: 0;
            left: -150px;
            overflow: hidden;
            background: -moz-linear-gradient(left,rgba(255,255,255,0)0,rgba(255,255,255,.2)50%,rgba(255,255,255,0)100%);
            background: -webkit-gradient(linear,left top,right top,color-stop(0%,rgba(255,255,255,0)),color-stop(50%,rgba(255,255,255,.2)),color-stop(100%,rgba(255,255,255,0)));
            background: -webkit-linear-gradient(left,rgba(255,255,255,0)0,rgba(255,255,255,.2)50%,rgba(255,255,255,0)100%);
            background: -o-linear-gradient(left,rgba(255,255,255,0)0,rgba(255,255,255,.2)50%,rgba(255,255,255,0)100%);
            -webkit-transform: skewX(-25deg);
            -moz-transform: skewX(-25deg);
        }
    style>
head>
body>
a class="floor" href="javascript:;">
    img src="./images/girl.jpg" height="475" width="760" alt="">
a>
body>
html>