移动端1px边框解决方案

.border-1px {
  position: relative;
}
.border-1px:after {
  position: absolute;
  content: '';
  top: -50%;
  bottom: -50%;
  left: -50%;
  right: -50%;
  -webkit-transform: scale(0.5);
  transform: scale(0.5);
  border-top: 1px solid #666;
}
@media (-webkit-min-device-pixel-radio: 1.5), (min-device-pixel-radio: 1.5) {
  border-1px::after {
    -webkit-transform: scaleY(0.7);
    transform: scaleY(0.7);
   }
}
@media (-webkit-min-device-pixel-radio: 2), (min-device-pixel-radio: 2) {
  border-1px::after {
    -webkit-transform: scaleY(0.5);
    transform: scaleY(0.5);
  }
}