Ruben, the issue is not anything to do with forum styles. Its a css block container issue within the actual template. This issue has been resolved in the upcoming version of UBB.threads.

Digitalgas, thanks for reporting this and bringing it to our attention so it could be fixed. Every item that gets reported, helps! thumbsup

Current developer of UBB.threads PHP Forum Software // 7.7.4 released!
isaac @ // my forum @