Change font size in Genesis Responsive Slider

Can you tell me how to change the font size in the slider to h1.

h1 is currently – color: #e52a88;
font-size: 36px;
font-size: 2.25rem;

I currently have this for the slider – .slide-excerpt h2 a {
color: #e52a88 !important;

When I changed the h2 to h1 the colour changed to the default link colour. It did not stay at #e52a88.

Also I’d like the h1 size to be 2.7rem but when I changed the size nothing happened. Do I also need to change the 36px size.

Many thanks