Dynanmic Header changed my blog's width

After installing Dynanmic Header and playing around with different headers i realised i didn’t really like it. After browsing several posts to see what it would like, i noticed that the width of my blog had been changed. At the bottom I now had a scroll bar like i have the normal vertical one at the right of the screen on each web page ( if the page is big, of course). How can i change that back ? I deleted the plugin, deleted the folder i had made with the FTP, called header_images.
Edited the style.css with what i read online but nothing seams to work. How can i have my old witdh back ?
my site is http://www.roofvoel.com, click on any post to see what i mean, it doesn’t show on the home page.

[duplicate: http://wordpress.org/support/topic/plugin-dynamic-headers-dynamic-header-changed-my-blogs-width?replies=1 – closed]