Design Custom Select and/or Add to Cart Button (E-Com)

Hello everyone,

I am currently in the process of integrating a store on a website. Is there a way to customize the default select field? I would even work with the default dropdown pattern but I would like to style the field even if it is not active. For example, the chevron hangs on the right side of the box, it’s too close to the border. Can I customize that?
Thanks and best regards,
Seb