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>
No logic changes — whitespace and indentation only. These were flagged
by the pre-commit hook when running lint after layout.css was modified.
Refs #64
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
