What do you mean by 'more flexibility to position'? You can position that popup you showed anywhere you like. E.g.
Code:
.active .pop_menu {
background-color: #F594A2;
color: #FFFFFF;
display: block;
left: 80px;
padding: 0.6em;
position: absolute;
width: 12em;
}
There are plenty of tooltip tutes out there, though the ones I've bookmarked tend to be hover examples rather than click ones.
Image-free CSS Tooltip Pointers - A Use for Polygonal CSS? | Filament Group, Inc., Boston, MA
Colortip - a jQuery Tooltip Plugin | Tutorialzine demo
Disjointed Rollover - CSS tooltip
Bookmarks