为博客的logo添加闪光效果的css

效果参见本博客左上角logo。 ：）

#site-banner{
    position: relative;
    overflow:hidden;
    margin: 0;
}
#site-banner:before {
    content:"";
    position:absolute;
    left:-100px;
    top:-50px;
    width:200px;
    height:3px;
    border-top:9px solid rgba(255,255,255,.5);
    border-bottom:5px solid rgba(255,255,255,.75);
    transform:rotate(-70deg);
    animation:bannerflash 8s ease-out 2s infinite;
}
@keyframes bannerflash {
0% { left:-100px; top:-50px }
30% { left:120px; top:50px }
to { left:120px; top:50px }
}