The customization I am looking for is things like the color of the fill fields, color of text etc. Mostly I am looking to adjust things like padding on checkout page. The is a huge gap at the top of the checkout page and everything is spread out way more space than is necessary.
The checkout page is too dark and not really enticing to a purchaser.
Lastly, the checkout page on mobile is not responsive. text is spilling onto next lines and things are getting pushed around.