Twenty Eleven Title Area

First ensure you have either a Child Theme or Custom CSS plugin.

Then use Firebug or another suitable browser developer tool to expose the CSS selectors necessary to target the Twenty Eleven Title Area of the webpage.

Then use the CSS selectors from Firebug (or relevant tool) and create a new style in your Child Theme style.css file or the Custom CSS section of the dashboard.

If you’re stuck on what CSS you need to add, you may be better asking in a forum like http://csscreator.com/forum