<!DOCTYPE html> <html> <body> <style> body { background: black; margin: 0; padding: 0; } .dor { display: block; width: 50px; height: 50px; background: red; border: 20px solid green; position: absolute; left: 100px; top: 100px; box-sizing: border-box; border-bottom-color: blue; } </style> <div class="dor"></div> </body> </html>
