v0.6.0

[0.6.0] — 2026-04-23

Added

• muriel.oklch module. Stdlib-only OKLCH / OKLab conversion
  (Ottosson 2020 / CSS Color Module Level 4), CSS oklch() parser
  covering the full CSS 4 grammar (percentages, angle units, none,
  legacy commas, alpha tolerated-and-discarded), sRGB gamut check, and
  chroma-bisection clamp that preserves L and h. Roundtrip is
  bit-exact on sRGB integer channels; primaries match Ottosson's
  reference values to four decimals.
• contrast.parse_color accepts oklch(...). Every existing
  contrast helper — contrast_ratio, check_text_pair, audit_svg
  — now accepts OKLCH inputs transparently via a lazy import.
  Out-of-gamut OKLCH is auto-clamped so hue and lightness are
  preserved instead of hard-clipping the channel.
• CLI. python -m muriel.oklch <color> inspects any color
  (hex / rgb() / named / oklch()) and reports hex, sRGB, OKLCH,
  and gamut status; --clamp additionally reports the chroma-clamped
  OKLCH and ΔC for out-of-gamut OKLCH inputs.
• brand.toml schema v2 covering the full design-token surface:
  [spacing], [radii], [elevation] structural ramps;
  [typography.scale] named type scale (display, h1–h4, body, body_small,
  caption, label, mono); [semantic.*] {text, surface, border} trios
  replacing the ad-hoc note/tip/warning/important fields;
  [viz] categorical / sequential / diverging palettes;
  [iconography] + [imagery] (with crop_policy hook into smartcrop);
  [logo] variants (wordmark / monogram / stacked / horizontal) with
  clear-space and min-width rules; [voice] adjectives + say-yes /
  say-no; [a11y] floors (min_contrast_ratio, min_hit_target_px,
  focus_ring_*, motion_reduce_policy).
• Brand-driven contrast floor. StyleGuide.audit_contrast() now
  defaults to the brand's own a11y.min_contrast_ratio (falls back to
  muriel's universal 8.0) instead of requiring an explicit argument.
• CSS vars emitter expansion. to_css_vars() now emits the full
  token surface: semantic-state trios, spacing / radii / elevation
  ramps, motion durations + easings, the full type scale (size / weight
  / line-height / tracking per role), and a11y hooks.

Changed

• examples/muriel-brand.toml and examples/example-brand.toml
  rewritten against v2, each populating every optional block.
• examples/example-brand.toml named and viz.categorical entries
  bumped to clear muriel's 8:1 floor (wildflowers, tiedye,
  violet); accent_decorative now actually fails 8:1 to match its
  role.
• muriel/tools/venn.py _region_colors ported off the v1
  colors.{tip,warning,important} fields to the v2
  viz.categorical palette with semantic.* fallback.