feat: polish hero, theme, and icon styling

[robert-7]

What changed

• Refined the social/icon coloring across the site so the header, footer, and contact links share the intended palette.
• Improved the light theme visuals in the hero so it feels more polished and consistent with the rest of the page.
• Fixed the mobile hero layout so the featured projects window no longer overlaps the intro content.

Why

This branch is a small UI polish pass across the homepage, focused on making the first screen read better on mobile and making the theme/icon styling feel more intentional in both light and dark modes.

Result

The homepage now has cleaner spacing on phones, more consistent icon colors, and a nicer light-theme presentation without changing the overall structure of the site.