Add to Cart – half coloured button

After a lot of digging around with css, php etc, I finally got the ‘Add to Cart to show.

The odd thing now is that the colour of the button is only half showing, see https://www.mhscot-consultancy.co.uk/product/project-management/

I’ve spent another 5/6 hours trying to fix it, but no solution.

Can anyone help?

Thanks

Catherine