Comment mettre l'image dans le bouton CSS

input.button-add {
  height: 32px;
  padding-left: 36px;
  padding-right: 10px;
  border: 1px solid #000000;
  background: #ff9900 url("http://placehold.it/16x16") no-repeat 10px center;
  cursor: pointer;
}
Smiling Skunk