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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