Tab borders are disabled in text widgets

Hi,

I started to use WordPress a week ago and decided to go for the Kippis theme. The only real issue I’ve had so far is to get visible borders in tables.
I’ve now managed to enable this in standard posts (by editing the table, td, and tr definitions in style.css) but I haven’t found any way to display table borders in a Text Widget.

Any help or suggestion is welcome!

Best Reg

–akeh