| <!DOCTYPE html> |
| <!-- |
| | A computed value of "auto" for "margin-left" or "margin-right" becomes |
| | a used value of "0". |
| | https://www.w3.org/TR/CSS21/visudet.html#inline-width |
| --> |
| <html> |
| <head> |
| <style> |
| .zero-width { |
| background-color: #f44336; |
| } |
| .non-zero-width { |
| background-color: #4caf50; |
| } |
| .container { |
| display: inline-block; |
| height: 100px; |
| } |
| .auto-margin { |
| margin: 0 auto; |
| } |
| .non-auto-margin { |
| margin: 0 50px; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="non-zero-width container"> |
| <span class="non-auto-margin"></span> |
| </div> |
| <div class="zero-width container"> |
| <span class="auto-margin"></span> |
| </div> |
| </body> |
| </html> |
