1html {
2 background: url(images/bg.jpg) no-repeat center center fixed;
3 -webkit-background-size: cover;
4 -moz-background-size: cover;
5 -o-background-size: cover;
6 background-size: cover;
7}
1/* with CSS 3 */
2#yourdiv {
3 background: url('bgimage.jpg') no-repeat;
4 background-size: 100%;
5}