How to set width for a border in css?

The border-width can be in a percentage of the width, or as one of three shortcut values.
The following table lists the values for the border-width Property

Value Description
length value Sets the border width to a length in CSS measurement units such as em, px, or cm.
%value Sets the border width to a percent of the width of the area around.
thin Sets the border width to thin, the actual value is defined by browser
medium Sets the border width to medium, the actual value is defined by browser
thick Sets the border width to thick, the actual value is defined by browser
The following css uses the pixel to define the border width.

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