e4539ed0f0
Replaces bg-white, text-brand-navy, border-brand-sand, text-gray-*, bg-[#2A2A2A], bg-brand-purple/15, hover:bg-brand-sand, etc. across all 35 .svelte files with semantic token utilities (bg-surface, text-ink, border-line, bg-pdf-bg, bg-nav-active, bg-muted, text-accent, bg-primary, ...). Also adds CSS filter: invert(1) in layout.css for De Gruyter <img> icons in dark mode, excluding icons that carry .invert already (to prevent double-inversion). Closes #64 Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>