Check out example codes for "media querycss". It will help you in understanding the concepts better.

Code Example 1

@media only screen and (max-width: 600px) {
  body {

   
background-color: lightblue;
  }
}

Code Example 2

CSS @media Rule

Example
Change the background color of the <body> element to "lightblue" when the browser window is 600px wide or less:

Syntax
@media only screen and (max-width: 600px) {
  body {
    background-color: lightblue;

    }
}

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