/* =====================================================================
   brand-system.css — READ THE GARDEN
   A′ Quiet Editorial / Field Journal — TOKEN 正本
   ---------------------------------------------------------------------
   仕様: ops/brand/BRAND-SYSTEM-A-PRIME.md（Founder確定 2026-08-29 / D-011）
   B（Masthead）・C（Plan View）は ARCHIVED → ops/wip/_archive/brand-bc/

   このファイルは「値」だけを持つ。構造・レイアウトは styles.css。
   値を変えることは Brand の変更 = RED。AI は単独で変更しない。

   フォントはセルフホスト（B-5⑤）。Google Fonts CDN の <link> を書かない。
   ===================================================================== */

/* ---------- self-hosted fonts (SIL OFL 1.1) -------------------------
   Re-enabled 2026-08-29 after the files were rebuilt (Y-056).

   History, so this is not repeated: the previous files were the wrong Google
   Fonts subsets — Fraunces vietnamese, Lora cyrillic-ext, Courier Prime
   latin-ext — containing 0–1 of 58 basic latin letters. The browser reported
   nothing; it fell back silently, so the site looked fine and was not A′.

   Current files are subset from the upstream variable/static originals in
   ofl/ at google/fonts, with the licences kept beside them in _src/ as OFL 1.1
   requires. Unicode range covers latin, latin-1, latin-ext (this is what
   carries Ō/ō for Tōfuku-ji — the plain "latin" subset does NOT), plus the
   punctuation A′ actually uses: · — – ’ ‘ ” “ … ¥.

   Variable axes are preserved: Fraunces wght 100–900 (+opsz/SOFT/WONK),
   Lora wght 400–700. Do not instance them to a static weight.

   Gate: `python3 tools/check-fonts.py` must PASS. It reads the cmap, not the
   filename, and commenting a face out does not make it pass.
   ------------------------------------------------------------------- */
@font-face { font-family:"Fraunces";      src:url("/fonts/fraunces.woff2") format("woff2");
             font-weight:100 900; font-style:normal; font-display:swap; }
@font-face { font-family:"Lora";          src:url("/fonts/lora.woff2") format("woff2");
             font-weight:400 700; font-style:normal; font-display:swap; }
@font-face { font-family:"Courier Prime"; src:url("/fonts/courier-prime.woff2") format("woff2");
             font-weight:400; font-style:normal; font-display:swap; }

:root {
  /* ---- Color: White base + single muted moss accent ----------------
     全比率は WCAG 2.1 相対輝度式で 2026-08-29 に実測。
     色を1つ足すこと・彩度を上げることは Brand 変更（RED）。 */
  --ground:      #FBF9F4;  /* White base (warm ivory)                   */
  --ground-deep: #F4F0E6;  /* 1ページに1〜2回まで。帯・プレート地       */
  --ink:         #23211C;  /* 15.28:1 on ground — AAA                   */
  --ink-quiet:   #6B665C;  /*  5.42:1 — AA 全サイズ。ラベル・注記       */
  --ink-faint:   #746D61;  /*  4.86:1 — AA 全サイズ。placeholder 文字   */
  --moss:        #515C4D;  /*  6.68:1 — AA 全サイズ。線と文字のみ       */
  --hairline:    #E6E0D2;  /*  1.25:1 — 罫線専用。テキストに使わない    */

  /* ---- Typography -------------------------------------------------- */
  --font-display: "Fraunces", "Iowan Old Style", Palatino, Georgia, serif;
  --font-body:    "Lora", "Iowan Old Style", Palatino, Georgia, serif;
  --font-label:   "Courier Prime", ui-monospace, "SFMono-Regular", Menlo, monospace;

  --type-display: clamp(2.5rem, 1.6rem + 3.9vw, 4.6rem);
  --type-h2:      clamp(1.6rem, 1.3rem + 1.3vw, 2.3rem);
  --type-h3:      clamp(1.15rem, 1.05rem + 0.5vw, 1.4rem);
  --type-body:    clamp(1.02rem, 0.98rem + 0.2vw, 1.12rem);
  --type-lede:    1.06em;   /* relative to body — BRAND-SYSTEM §3 */
  --type-label:   0.72rem;
  --type-cta:     0.78rem;
  --type-table:   0.94em;   /* relative to body — long-form document tables */
  --type-code:    0.88em;   /* relative to body — inline identifiers        */

  --lh-display: 1.04;
  --lh-h2:      1.18;
  --lh-body:    1.78;   /* 下げない。密度を上げると観光LPに近づく */
  --lh-lede:    1.72;

  --ls-display: -0.015em;
  --ls-h2:      -0.01em;
  --ls-label:    0.2em;
  --ls-cta:      0.18em;

  /* ---- Spacing: large whitespace ----------------------------------- */
  --space-3xs: 0.25rem;
  --space-2xs: 0.5rem;
  --space-xs:  0.75rem;
  --space-s:   1rem;
  --space-m:   1.5rem;
  --space-l:   2.4rem;
  --space-xl:  3.5rem;
  --space-2xl: 5rem;

  --gap-section: clamp(6rem, 4rem + 9vw, 11rem);  /* 縮めない */
  --measure:      31rem;   /* 本文 62–66字 */
  --measure-wide: 44rem;   /* 写真プレート等 */
  --pad-inline:   1.5rem;

  /* ---- Lines & motion ---------------------------------------------- */
  --rule: 1px solid var(--hairline);
  --ease: 0.18s ease;
}

/* Dark mode は意図的に未実装。A′ の白基調と写真の見え方を両立する
   dark palette が未検証のため。検証していない色は出さない。 */