This property controls the thickness (width) of the right border of an element's rendering box. Negative values are not allowed.
Explicitly sets the value of this property to that of the parent.
thin | medium | thick:
Renders a "thin", "medium" or "thick" border on the right side of the element's rendering box. The actual thickness of these border values is not specified, but "thin" should have a smaller thickness than "medium", which should have a smaller thickness than "thick".
Sets the width of the border on the right side of the element's rendering box to an explicit measurement.