background image aspect ratio 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: how to change the width of a background image in css

#example1 {		/* Example1 has an auto background size */
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: auto;
}

#example2 {		/* Example2 has an fixed background size */
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: 300px 100px;
}