Check out example codes for "what are the viewport based units in html". It will help you in understanding the concepts better.

Code Example 1

/*vh viewport height and vw viewport width*/
/*example*/
div
{
  display: inline-block;
  height: 100vh; /*THis will set height equal to the height of windows*/
  width: 100vw/*This will set width equal to width of windows*/
}

Code Example 2

css vs height

Code Example 3

The viewport based units are:
vh , vw , vmin, vmax .

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