<html> <head> <style> div { width: 100px; } div.a { height: 30px; background: lightblue; } div.b { height: 100px; background: lightgreen; } div.c { height: 10px; background: black; } </style> </head> <body> <div class="a"></div> <div class="b"></div> <div class="c"></div> </body> </html>