Woocommerce buttons on mobile

Hi!

First of all I LOVE the theme! I have a small problem though:

I’ve styled the Woocommerce buttons on my website (https://artstyledesigns.com/) but 2 buttons (update cart + proceed to Paypal) still doesn’t look like the rest of the buttons on my iPhone. Could you tell me where can I find that CSS file about the mobile Woocommerce? Or please tell me what classes can I use in CSS to overwrite their current style!

I’m using a child theme.

The problem appears just on mobile, these buttons look great on computer.

Thanks!