CKAN is highly customisable. See screenshots below for examples of various themed CKAN instances. You can customise the appearance of your CKAN portal yourself using the documentation here: http://docs.ckan.org/en/latest/theming.html or alternatively the CKAN team or a CKAN partner can do this for you as part of a support contract, CKAN Hosted plan or general set-up fee. See our Pricing Page or Contact us for more details.
Here are some examples of CKAN portals around the world: