Changing font colour on Chunk Theme by Automattic

Hi,

Im trying to change the font colour on the Chunk theme but it is not accepting the change on the css style sheet.

My site is morethanblack.co.uk

I want all the text to be black and when hovering over the text i want it to be black also but i cannot get it to change from the grey and aqua colour (#36bcab;). This colour is not found anywhere in the stylesheet but is still appearing on the site.

Can anyone help please? Thanks