移动端一物理像素边框的设置

　　

.border-1{
    position: relative;
}
.border-1:after{
    content: ' ';
    position: absolute;
     100%;
    left: 0;
    bottom: 0;
    border-top: 1px solid rgba(7, 17, 21, 0.1);
}
@media (-webkit-min-device-pixel-ratio: 1.5),(min-device-pixel-ratio: 1.5) {
    .border-1:after{
        -webkit-transform: scaleY(0.7);
        transform: scaleY(0.7);
    }
}

@media (-webkit-min-device-pixel-ratio: 2),(min-device-pixel-ratio: 2) {
    .border-1:after{
        -webkit-transform: scaleY(0.5);
        transform: scaleY(0.5);

    }
}