Check out example codes for "css background shorthand". It will help you in understanding the concepts better.

Code Example 1

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

Code Example 2

/*CSS background Property

Example
Set different background properties in one declaration:
*/
body
 { 
   background: lightblue url("img_tree.gif") no-repeat fixed center; 
 }

Code Example 3

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

Code Example 4

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

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

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