full screen background image size code example

Example 1: css background image size to fit screen

html {
    height: 100%
}
body {
    background-image:url("../images/myImage.jpg");
    background-repeat: no-repeat;
    background-size: 100% 100%;
}

Example 2: css background image size fit screen

html { 
  background: url(images/bg.jpg) no-repeat center center fixed; 
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}