CSS – Resize your background image

                                          #resize-image {
       /* Just imagine that the image_1.png is 200x400px */   background: url("image_1.png") top left no-repeat;
       -moz-background-size: 100px 200px;
       -o-background-size: 100px 200px;
       -webkit-background-size: 100px 200px;
}