This only occore when you are loged in, the margin top is to let your website display under the admin bar (and not behind). when youre logged out the css disapears.
Thanks for quick respond, i will try it out.
Solved the problem, was a conflict with WordPress Post Tabs plugin.
Worked on main blog, but on the others the tabs get activated even when the tab isn’t activated.
Didn’t need the plugin, so problem solved
