Check out example codes for "mark tag in html". It will help you in understanding the concepts better.

Code Example 1

<mark>text</mark>

Code Example 2

<style>
mark { 
  background-color: yellow;
  color: black;
}
</style>

<mark>Highlighted text!!</mark>

Code Example 3

mark {
  display: inline-block;
  line-height: 0em;
  padding-bottom: 0.5em;
}

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