Writing/Correcting CSS script and wordpress issues

Our current developer is on leave and we need someone to write basic script for our website the back end is done in wordpress therefore an understanding of this is needed and also the themes and layout is written in CSS so an understanding of this is also a must. You give me estimation for the time needed for job discussed and will be paid hourly. This will be on going work with the possibility of more website design if you are able to produce the work.