Values

<width>

The border width. The lengths corresponding to thin, medium and thick are not specified, but the values are constant throughout a document and thin ≤ medium ≤ thick.

<length>	It may not be negative.
thin
medium
thick

<style>

The border style.

none	No border. Color and width are ignored (i.e., the border has width 0, unless the border is an image, see background-image).
hidden	Same as none, but has different behavior in the border conflict resolution rules for border-collapsed tables.
dotted	A series of round dots.
dashed	A series of square-ended dashes.
solid	A single line segment.
double	Two parallel solid lines with some space between them. The thickness of the lines is not specified, but the sum of the lines and the space must equal border-width.
groove	Looks as if it were carved in the canvas. This is typically achieved by creating a “shadow” from two colors that are slightly lighter and darker than the border-color.
ridge	Looks as if it were coming out of the canvas.
inset	Looks as if the content on the inside of the border is sunken into the canvas. Treated as ridge in border-collapsed tables.
outset	Looks as if the content on the inside of the border is coming out of the canvas. Treated as groove in border-collapsed tables.

<color>

The border color.