Help with tiny CSS tweak

Hi SI Team

I have this is my custom css file:

/* controls the font ENTER CODE BELOW  */

a {

    color: #0c9019 !important;

}

Which as far as I can tell takes care of the colour on my site text links etc.

This is all well and good but I do not want it taking effect here on the buttons etc:

https://www.finalbug.net/component/hikashop/product/23-fcpx-foundations

Hika Shop kindly gave me the following:

 a.hikabtn{ color: white !important; }

So I added 1+2 and made this:

/* controls the font ENTER CODE BELOW  */

a {

    color: #0c9019 !important;

    a.hikabtn{ color: white !important; }

}

But the text in the Hika Shop buttons is still green.

https://www.finalbug.net/component/hikashop/product/23-fcpx-foundations

Kindly advise what I am doing wrong

thanks

Paul