I changed the font sizes for two headings in the style.css - it made the whole website content invisible after 'working' for 5 minutes.
I changed everything back to how it was but my site looks the same: blank - only menu is visible in huge Fontsize.
I just realize that the whole site (menu and content) apprear together in 'one container' on the left side - I adjusted just the font size, any idea how that happened?
Solved with validator.w3.org
In theme Pre Nav text
was missing the closing >
This thread has been closed, thank you.