<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <div style="position: relative; 500px;height: 200px;border: 1px solid red;margin: 0 auto;"> <div style="position: absolute;left:0;bottom:0; 50px;height: 50px;background-color: black;"></div> </div> <div style="position: relative; 500px;height: 200px;border: 1px solid red;margin: 0 auto;"> <div style="position: absolute;right:0;bottom:0; 50px;height: 50px;background-color: black;"></div> </div> <div style="position: relative; 500px;height: 200px;border: 1px solid red;margin: 0 auto;"> <div style="position: absolute;right:0;top:0; 50px;height: 50px;background-color: black;"></div> </div> </body> </html>