CodePen

HTML

            
              <button type="submit" class="btn-save">Save</button>
            
          
!

CSS

            
              .btn-save:before {
  content: "";
  background: url('http://placekitten.com/25/25') no-repeat;
  display: inline-block;
  width: 25px;
  height: 25px;
}

.btn-save {
  border: 0;
  padding: 0;
  margin: 0;
  overflow: hidden;
  width: 25px;
  height: 25px;
}
            
          
!
? ?
? ?
Must be a valid URL.
+ add another resource
via CSS Lint

JS

            
              
            
          
!
Must be a valid URL.
+ add another resource
via JS Hint
Loading ..................