.icon {
    background-image: url('sprite-alert-black.png');
  }
  
  .icon-ic_error_black_24dp {
    background-position: -5px -5px;
    width: 24px;
    height: 24px;
  }
  
  .icon-ic_warning_black_24dp {
    background-position: -39px -5px;
    width: 24px;
    height: 24px;
  }