<!DOCTYPE HTML> <html> <head> <style> div { width: 200px; height: 200px; } #one { background-color: green; } #two { background-color: red; } #three { position: absolute; width: 500px; height: 500px; top: 0px; background-color: rgba(255,0,255,0.2); } </style> </head> <body> <div id="one"></div> <div id="two"></div> <div id="three"></div> </body> </html>