Check out example codes for "how to change the background color in css". It will help you in understanding the concepts better.

Code Example 1

body {
  background-color: lightblue;
}

Code Example 2

/* Use the following code: */
html {background-color: #fefefe;} 
/* You can change the hexedecimal code to RGB, RGBA, name & more colors!*/

Code Example 3

html,body {
  background-color: red;
}

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