Swaps navbar layout (theme toggle left, nav links right), replaces the
mobile dropdown with a fullscreen overlay whose items fly in top-to-bottom,
and renames the site-wide "slate" gray to "neutral" to remove a blue
undertone that clashed with the brand green. Also converts the flat
saturated-green YouTube and stats sections into dark backgrounds with
green used only as an accent, matching typical premium car-audio branding.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>