<!DOCTYPE html> <html> <head> <style type="text/css"> #b { height: 20px; background-color: green; } #c { margin-top: 30px; margin-bottom: 40px; height: 0; } #d { height: 10px; width: 100px; background-color: red; } #e { height: 20px; background-color: green; } </style> </head> <body> <div id="b"></div> <div id="a"> <div id="c"> <div id="d"></div> </div> </div> <div id="e"></div> </body> </html>
