WooCommerce Checkout Layout Cleanup

My WooCommerce checkout looks messy and I’d like it polished. The Billing details and Payment options areas show random gaps, uneven alignment, and fonts that don’t match the rest of the site.

Here’s what I need done:
• Trim every extra space or padding that pushes fields out of place.
• Re-organise the layout so input fields sit in clean, consistent columns—no more jagged edges.
• Tweak fonts and colours only where necessary so they inherit the site’s existing style guide.
. style the payment gateway box

Please work directly in a child theme or with custom CSS so updates remain safe from future WooCommerce or theme upgrades. Once finished, I’ll verify on desktop and mobile to confirm everything lines up, spacing is tight, and styling matches the brand palette.