/* ─────────────────────────────────────────────────────────
   ATRX — Institutional design tokens
   Aesthetic: Two Sigma / AQR register. White ground editorial.
   Single restrained accent. Type does the work.
   ───────────────────────────────────────────────────────── */

:root{
  /* Ground & ink — light mode (default) */
  --ground:        #FBFAF7;   /* warm bone */
  --ground-2:      #F2EFE8;   /* card / rule fill */
  --ground-3:      #E7E2D6;   /* divider stronger */
  --ink:           #111418;   /* near-black, slight warm */
  --ink-2:         #2A2E36;
  --mute:          #6B6F78;   /* secondary */
  --mute-2:        #9A9DA4;   /* tertiary / captions */
  --rule:          rgba(17,20,24,0.10);
  --rule-strong:   rgba(17,20,24,0.22);
  --hairline:      rgba(17,20,24,0.06);

  /* Accent — muted Prussian / steel. Single accent only. */
  --accent:        #1F3A5F;
  --accent-ink:    #FBFAF7;

  /* Semantic — subdued */
  --pos:           #2D5F3F;
  --neg:           #7A2E2E;
  --warn:          #8A6A2A;

  /* Families */
  --serif: "IBM Plex Serif", ui-serif, Georgia, "Times New Roman", serif;
  --sans:  "Inter", ui-sans-serif, -apple-system, "Helvetica Neue", sans-serif;
  --mono:  "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;

  /* Scale — 1.25 minor third */
  --step--1: 13px;
  --step-0:  16px;
  --step-1:  18px;
  --step-2:  22px;
  --step-3:  28px;
  --step-4:  36px;
  --step-5:  48px;
  --step-6:  64px;
  --step-7:  84px;

  /* Measure */
  --measure: 66ch;       /* ~680px at 17px */
  --measure-wide: 92ch;
  --page-max: 1280px;
  --gutter: clamp(20px, 4vw, 56px);

  /* Density (tweakable) */
  --dens: 1;             /* 0.85 compact · 1 default · 1.15 spacious */
  --rhythm: calc(28px * var(--dens));
}

/* Dark ground */
[data-theme="dark"]{
  --ground:        #0C1016;
  --ground-2:      #141922;
  --ground-3:      #1E2430;
  --ink:           #EDEAE1;
  --ink-2:         #C9C6BE;
  --mute:          #8A8F9A;
  --mute-2:        #5E636D;
  --rule:          rgba(237,234,225,0.12);
  --rule-strong:   rgba(237,234,225,0.24);
  --hairline:      rgba(237,234,225,0.06);
  --accent:        #8FB4DC;
  --accent-ink:    #0C1016;
}

/* Accent presets (tweakable) */
[data-accent="prussian"]  { --accent:#1F3A5F; }
[data-accent="prussian"][data-theme="dark"] { --accent:#8FB4DC; }
[data-accent="gold"]      { --accent:#8F6F2A; }
[data-accent="gold"][data-theme="dark"]     { --accent:#C5A059; }
[data-accent="ink"]       { --accent:#111418; }
[data-accent="ink"][data-theme="dark"]      { --accent:#EDEAE1; }
[data-accent="slate"]     { --accent:#3E5366; }
[data-accent="slate"][data-theme="dark"]    { --accent:#A9BACC; }

/* Type pairing presets (tweakable) */
[data-type="plex"]{
  --serif:"IBM Plex Serif", ui-serif, Georgia, serif;
  --sans:"Inter", ui-sans-serif, sans-serif;
  --mono:"IBM Plex Mono", ui-monospace, monospace;
}
[data-type="fraunces"]{
  --serif:"Fraunces", ui-serif, Georgia, serif;
  --sans:"Inter", ui-sans-serif, sans-serif;
  --mono:"JetBrains Mono", ui-monospace, monospace;
}
[data-type="crimson"]{
  --serif:"Crimson Pro", ui-serif, Georgia, serif;
  --sans:"Inter", ui-sans-serif, sans-serif;
  --mono:"JetBrains Mono", ui-monospace, monospace;
}

/* Density presets */
[data-density="compact"]   { --dens: 0.85; }
[data-density="default"]   { --dens: 1; }
[data-density="spacious"]  { --dens: 1.18; }