Torn contains a top area that is fixed hight with the Sidebar and Main content areas.  Below that are three fluid columns with gradient backgrounds.  Column heights can be locked by adjusting the min-height in main.css or by adding a Number Page Attribute 'lower_boxes_height' to control heights on individual pages.  The logo can be changed by replacing  themes/images/logo.png, with a ScrapBook image named 'logo or assigning File/Text attributes 'logo'

Live Demo @ weblicating.com/c5themes/torn

Concrete5.5 Ready!