background property in css3 code example

Example 1: background css

/* Color (Example: red): */
html,body {
  background-color: red;
}

/* Image (Example: your.picture): */
html,body {
  background-image: url("your.picture");
}

Example 2: background css

body {
  background: #ffffff url("img_tree.png") no-repeat fixed right top;
}