Most of the time you wouldn't get anyone to answer here for your question because you are asking for free customization assistance. This area is for pligg core support. I just happened to come across your post and I thought I might point you in the right direction.
You can modify the css but if you've done it correctly you will still need to delete pligg's template cache, which you can find from the main pligg admin page.
“Thank you Yankidank...”
Just for fun, and while I forgot where I grabbed the initial code..
“I suggest you use Winmerge to compare the source code between your old copy and the new version to...”
“Sorry to take a while to get back to you. I assume that you are still having this problem? I am...”
“Well there certainly isn't a simple way to do it, so I'm going to say no....”
New user? Create a new account