I've tried to bold my Page Menu items by inserting this into CSS:

div#menu1 ul.rMenu li a:link {text-decoration: none; font-weight: bold;},
div#menu1 ul.rMenu li a:hover {text-decoration: none; font-weight: bold;},
div#menu1 ul.rMenu li a:visited {text-decoration: none; font-weight: bold;},
div#menu1 ul.rMenu li a:active {text-decoration: none; font-weight: bold;},

This works until you visit a page. After you click on it, the "visited" status clears the bolding. Not sure what I didn't cover here, or if maybe I have an obvious typo I'm missing.

Site is www.douglaspeckphotography.com, click on Admin Login to get past the splash page and see the menus in action.

This is from w3schools.com

Note: a:hover MUST come after a:link and a:visited in the CSS definition in order to be effective!!
Note: a:active MUST come after a:hover in the CSS definition in order to be effective!!
Note: Pseudo-class names are not case-sensitive.

So in your case the sequence should be the following without the commas

div#menu1 ul.rMenu li a:link {text-decoration: none; font-weight: bold;},
div#menu1 ul.rMenu li a:visited {text-decoration: none; font-weight: bold;}
div#menu1 ul.rMenu li a:hover {text-decoration: none; font-weight: bold;}
div#menu1 ul.rMenu li a:active {text-decoration: none; font-weight: bold;}

You could also try the following since all the items are styled the same.

div#menu1 ul.rMenu li a{text-decoration: none; font-weight: bold;}

You said you inserted this into CSS. That means The CSS Inserts box correct?

The first method worked, the second one (which I tried first in the CSS Inserts) didn't. Good enough for me, thanks!