| <!DOCTYPE html> |
| <!-- |
| | The following constraints must hold among the used values of the other |
| | properties: |
| | margin-left + border-left-width + padding-left |
| | + width |
| | + padding-right + border-right-width + margin-right |
| | = width of containing block |
| | |
| | If there is exactly one value specified as "auto", its used value follows |
| | from the equality. |
| | https://www.w3.org/TR/CSS21/visudet.html#blockwidth |
| --> |
| <html> |
| <head> |
| <style> |
| .containing-block { |
| background-color: #2196f3; |
| padding: 10px 0; |
| margin-bottom: 10px; |
| width: 500px; |
| } |
| .block { |
| /* TODO: Add borders when supported. */ |
| background-color: #3f51b5; |
| display: block; |
| height: 5px; |
| padding: 0 100px; |
| } |
| .auto-margin-left { |
| margin-left: auto; |
| margin-right: 50px; |
| width: 100px; |
| } |
| .auto-margin-right { |
| margin-left: 50px; |
| margin-right: auto; |
| width: 100px; |
| } |
| .auto-width { |
| margin-left: 50px; |
| margin-right: 50px; |
| width: auto; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="containing-block"> |
| <div class="auto-margin-left block"></div> |
| </div> |
| <div class="containing-block"> |
| <div class="auto-margin-right block"></div> |
| </div> |
| <div class="containing-block"> |
| <div class="auto-width block"></div> |
| </div> |
| </body> |
| </html> |
