Check out example codes for "border width css". It will help you in understanding the concepts better.

Code Example 1

.element {
  border-width: 2px;
}

Code Example 2

element {
	border-width: 10px;
  	/* Or use shorthand border property */
  	/* width style colour */
  	border: 10px solid black;
}

Code Example 3

/* Answer to: "css border width" */

/*
  The border-width property specifies the width of the four borders.

  The width can be set as a specific size (in px, pt, cm, em, etc)
  or by using one of the three pre-defined values: 
  thin, medium, or thick:
*/

p.one {
  border-style: solid;
  border-width: 5px;
}

p.two {
  border-style: solid;
  border-width: medium;
}

p.three {
  border-style: dotted;
  border-width: 2px;
}

p.four {
  border-style: dotted;
  border-width: thick;
}

/*
  For more information go over to:
  https://www.w3schools.com/css/css_border_width.asp
  and you may also want to check out:
  https://www.w3schools.com/cssref/pr_border-width.asp
*/

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