Whenever I use the shortcode [download_now id="123" variation="123" text="Get it Free!"] The button that appears looks like the image below. It seems to be trying to pull some styling from my theme but not perfectly.

How can I manually edit this? I need the CSS to make the text white and centered perfectly in the square. Or does someone know where I put the CSS? This button seems to be calling the following classes: somdn-download-archive single_add_to_cart_button button