<!DOCTYPE html> <html><head> <style> #outer { opacity: 0.8; background-color:red; width: 200px; } #inner { opacity: 0.6; background-color:white; color:white; } </style> </head> <body> <div id="outer"> <div style="width:200px; height:200px; background:black;"></div> <div id="inner"> <div style="width:200px; height:200px; background:black;"></div> <div style="width:200px; height:200px; background:rgb(50,50,50);"></div> </div> </div> </body></html>