submenus have too much white space

I have the following to make the top-level menu space out across the top:

I have the submenu width set to 18.5, the smallest I can have it without the background dropdown arrow go behind the text. The problem is there is 50 px of white space on the left of submenu text and like 65px on the right, forcing the second level sub-submenu items way off to the right. Seeing your posts, I've tried several things under the selectors;

like width: 14em;, smaller margins, negative margins, text-align: left;, background-position: right; ( to move arrows over) but everything seems to squeeze text and arrows together without getting rid of white space) On a prior post I had ul.rMenu li {width: 25%} on top menu then switched to margins as per above, and thought I had it solved with your help.

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