You can control the thickness, or width, of borders with the
border-width property. The value of
border-width is given in pixels.
In the example above, the solid borders of all paragraphs on the page would be set to a thickness of 5 pixels.
It's also possible to also set the
border-width property to one of the following named thicknesses:
While these values are perfectly valid, you may not see them often, but it's good to know that they exist.