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<!-- SPDX-FileCopyrightText: 2025-2026 Marcus Quinn -->

# Design System: Claude — Do's and Don'ts

## Do

- Use Parchment (`#f5f4ed`) as the primary light background — the warm cream tone IS the Claude personality
- Use Anthropic Serif at weight 500 for all headlines — the single-weight consistency is intentional
- Use Terracotta Brand (`#c96442`) only for primary CTAs and the highest-signal brand moments
- Keep all neutrals warm-toned — every gray should have a yellow-brown undertone
- Use ring shadows (`0px 0px 0px 1px`) for interactive element states instead of drop shadows
- Maintain the editorial serif/sans hierarchy — serif for content headlines, sans for UI
- Use generous body line-height (1.60) for a literary reading experience
- Alternate between light and dark sections to create chapter-like page rhythm
- Apply generous border-radius (12–32px) for a soft, approachable feel

## Don't

- Don't use cool blue-grays anywhere — the palette is exclusively warm-toned
- Don't use bold (700+) weight on Anthropic Serif — weight 500 is the ceiling for serifs
- Don't introduce saturated colors beyond Terracotta — the palette is deliberately muted
- Don't use sharp corners (< 6px radius) on buttons or cards — softness is core to the identity
- Don't apply heavy drop shadows — depth comes from ring shadows and background color shifts
- Don't use pure white (`#ffffff`) as a page background — Parchment (`#f5f4ed`) or Ivory (`#faf9f5`) are always warmer
- Don't use geometric/tech-style illustrations — Claude's illustrations are organic and hand-drawn-feeling
- Don't reduce body line-height below 1.40 — the generous spacing supports the editorial personality
- Don't use monospace fonts for non-code content — Anthropic Mono is strictly for code
- Don't mix in sans-serif for headlines — the serif/sans split is the typographic identity
