<!DOCTYPE html> <html> <head> <style type="text/css"> html { margin: 0; padding: 30px 20px; background-color: green; } body { margin: 0; padding: 0 30px; background-color: red; } div { background-color: blue; height: 20px; } </style> </head> <body> <div></div> </body> </html>
