The eventual interface design has arisen in various steps: from layout to concept design to adjustments. The following screenshots show the various steps in this process. 

The various steps At first a layout was agreed upon. The layout describes the position of the different parts such as main and subnavigation, search engine, content and others. Click here or on the image for an enlargement.

Subsequently three concepts were drawn up within the guidelines of the layout. Concept 1 can be enlarged by clicking on the image or here.

Concept 2 can be enlarged by clicking on the image or here.

The final concept can be enlarged by clicking on the image or here.