I tried to make the category menu in bold, but what am i missing ? I tried to insert the css:

ul#rMenu li.current-cat a:link,
ul#rMenu li.current-cat a:hover,
ul#rMenu li.current-cat a:visited,
ul#rMenu li.current-cat a:active
{
font-weight: bold;
}

but it doesnt work

I was looking for the same thing and found the css change needed to be done in header.php. The code is near the bottom of the file.

It works fine for me and now the code looks like this:

ul#rmenu li a:link, ul#rmenu li a:hover, ul#rmenu li a:visited, ul#rmenu li a:active
{
color: #<?php echo $bfa_ata_cat_menu_bar_link_color; ?>;
text-transform: <?php echo $bfa_ata_cat_menu_transform; ?>;
font: <?php echo $bfa_ata_cat_menu_font; ?>;
font-weight: bold;
}