By "lighter" I assume you mean lighter color.
You can modify an existing color to make it lighter by going to
Tools/Options/Color...select an unused color and click on Modify, you can
select a color from the Standard tab or you can make a custom color under the
custom tab. Then use that lighet color for your border.

HTH
JG

"Mary K" wrote:

How do I make the lightest border lighter in Excel?