<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN"> <html lang="en"> <head> <title>CSS Block Box Model: sane horizontal box model and minimum widths</title> <style type="text/css"> .container { width: 5em; } .test { margin-left: 0; border-left: 2em solid; padding-left: 0; width: auto; padding-right: 0; border-right: 2em solid; margin-right: 0; } .control { margin-left: 0; border-left: none; padding-left: 0; width: 5em; padding-right: 0; border-right: none; margin-right: 0; } div { background: navy; border-color: navy; height: 1em; } </style> </head> <body> <p>The following two DIVs should be the same width (resulting in a single 5 by 2 block).</p> <div class="container"> <div class="test"></div> </div> <div class="control"></div> </body> </html>