CSS3扫描动画效果

.swiper-animate {
    position: absolute;
    width: 100%;
    height: 100%;
    left:;
    top:;
    z-index:;
    background: linear-gradient(to bottom, transparent, #3e88f1);
    animation: scan 1.5s ease-in-out infinite;
    -webkit-animation: scan 1.5s ease-in-out infinite;
}

@keyframes scan {
    from {
        top: -667px;
    }/*网格移动到显示区域的外面*/
    to {
        top:;
    }
}

@-webkit-keyframes scan {
    from {
        top: -667px;
    }
    to {
        top:;
    }
}