.icon {
  display: inline-block;
  margin-right: 0.3rem;
  height: 32px;
  width: 32px;

  background: transparent url("../images/icon.png") no-repeat center center;

  vertical-align: text-top;
}

@media (-webkit-min-device-pixel-ratio: 1.5), (min-resolution: 144dpi) {

  .icon {
    background-image: url("../images/icon2x.png");
    background-size: 32px 32px;
  }

}

.icon {
  display: inline-block;
  margin-right: 0.3rem;
  height: 32px;
  width: 32px;

  background: transparent url("../images/icon.png") no-repeat center center;

  vertical-align: text-top;
}

@media (min-resolution: 144dpi) {

  .icon {
    background-image: url("../images/icon2x.png");
    background-size: 32px 32px;
  }

}

Remove the extra Webkit stuff
Remove the extra Webkit stuff
