<!DOCTYPE html> <html> <head> <style> div:empty { background: yellow; border: 1px solid black; height: 10px; padding: 0; margin: 0; } body > div:not(:empty) { width: 400px; } </style> </head> <body> <div style="width: 100px;"></div> <div style="width: 150px;"></div> <div> <div style="width: 200px;"></div> </div> <div> <div style="width: 200px;"></div> </div> <div> <div style="width: 300px;"></div> </div> <div> <div style="width: 200px;"></div> </div> <div> <div style="width: 300px;"></div> </div> <div style="padding: 0 100px;"> <div style="width: 200px;"></div> </div> <div style="padding: 0 100px;"> <div style="width: 300px;"></div> </div> <div style="border-width: 0 100px; border-style: solid; border-color: transparent;"> <div style="width: 200px;"></div> </div> <div style="border-width: 0 100px; border-style: solid; border-color: transparent;"> <div style="width: 300px;"></div> </div> </body> </html>