CMS for existing website

Hello I want a CMS added to an existing website. The website has 100 pages. It's made up of text, images and videos. The CMS should allow for the following: - Add, edit and delete text - Add, delete new pages - Add, delete images and videos The CMS should be easy to use and navigate through. The CMS can be code in any preferred language - but prefer WordPress or Joomla. The CMS should be integrated into the website without affecting the current website's look or feel. A sample of the CMS must be sent to the client for approval before fully integrating it in the website. Timeline: The CMS should be fully integrated in 4 days. Samples of previous CMS work are welcomed. Cost: $120 with potential bonus