I'm having the same issue, i put the code, but it doesn't seem to change anything. In another post i asked about removing the border and that worked, it's in the same css area of the module admin. SO i now have ( set the width to 260 trying to get it wider than what you had there but either way nothign changes). Is the width setting per item, or overall width?
#navigation .ux-menu A.ux-menu-link-level-0
{
line-height: 48px
}
#menu LI.ux-menu-item-level-0
{
width: 260px !important;
}
#menu .ux-menu A.ux-menu-link-level-0
{
line-height: 24px
}
.ux-menu A.ux-menu-link-level-0
{
border-style: none !important;
}
(p.s. I also tried putting the width/height alone without the border one and still nothing) The site is at
www.dorothyscloset.com/events/