The 'outline-width' property specifies the width for the outline of an element.
The outline properties create a uniform line around an object in order
to draw visual attention. An outline is slightly different than a border
in several ways: An outline is drawn starting "just outside the border
edge" and is allowed to be non-rectangular. Outlines are always rendered
on TOP of an element's rendering box and do not influence the
box's position or size calculation; the document does not need to be
re-flowed when a border is rendered or hidden, but the outline may
overlap other nearby elements.
Allowed Values
inherit
[CSS2] [O7]
Type: Explicit
Description:
Explicitly sets the value of this property to that of the parent.
thin | medium |
thick
[CSS2] [O7]
Type: Calculated
Description:
Renders a "thin", "medium" or "thick" outline
border for the element's rendering box. The actual thickness of
these outline values is not specified, but "thin" should have a
smaller thickness than "medium", which should have a smaller
thickness than "thick".
[length]
[CSS2] [O7]
Type: Explicit
Description:
Sets the width of the outline around the current element rendering box to
an explicit measurement.