backgorund img on entire page code example

Example 1: how to cover whole webpage by background image in html

background: url(images/bg.jpg) no-repeat center center fixed; 
  background-size: cover;

Example 2: full page background image in html

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;
}