伪类写border， transform: scale3d() 及兼容性

.top::before {
    content: "";
    position: absolute;
    left: 0;
    width: 200%;
    height: 0;
    border-top: 1px solid #cccccc;
    transform-origin: left top;
    transform: scale3d(0.5,0.5,0.5);
    -webkit-transform: scale3d(0.5,0.5,0.5); /* Chrome, Safari, Opera */
    -ms-transform: scale3d(0.5,0.5,0.5); /* IE 9 */
}
.top::after{

　　 content: "";
    position: absolute;
    left: 0;
    width: 200%;
    height: 0;

    border-bottom: 1px solid #cccccc;

    transform-origin: left top;
    transform: scale3d(0.5,0.5,0.5);
    -webkit-transform: scale3d(0.5,0.5,0.5); /* Chrome, Safari, Opera */
    -ms-transform: scale3d(0.5,0.5,0.5); /* IE 9 */
}