how to have background image cover entire page css 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 cover full background with css

<div id="bg">
  <img src="images/bg.jpg" alt="">
</div>