Margin 0 Auto 0 Auto

The eternal struggle of frontend developers! Wanted to solve crimes, ended up typing margin: 0 auto; repeatedly just to make divs behave. The classic CSS centering investigation - where you need detective-level skills to figure out why your element won't stay centered. And just when you think you've cracked the case, another div goes rogue. The title "Margin 0 Auto 0 Auto" is actually redundant CSS (just like most of our stylesheets), which makes it even funnier for those who've spent hours debugging layout issues.