[balinor]

No, you just need to use css, not the html 'border'. Copy this into your skin1.css file:

.main-border {border-left: 10px solid #000000; border-right: 10px solid #000000;}

Substitute the correct hex color for the #000000 (which is black) and adjust the width in pixels to whatever you want.

Now add this to the table tag in rectangle_top.tpl:

class="main-border"