Apply style sheets to an internal portal developed in PHP.

My client has used an internal developer to build a client facing portal in PHP and needs a developer who appreciates design and can use style sheets to improve the look of the portal. The portal works and so there is no need to change its core functionality at the moment - just aesthetics.

We have some ideas on improving the portal in the future and are open to any suggestions on improving the structure if need be, but the priority is the aesthetics.

The client would like the project complete before the end of the year so that they can release it to customers. However, the quicker the better.

I have attached a screenshot from the portal and also a few graphics of how we want it changed. We do not need a work of art, just something clean and simple. Many of the tabs/screens have the same layout and so the same styling can be applied across the portal.

We would like to see examples of portals/web applications you have worked on.