/* ============================================================
   The Alluvial — Color Tokens
   Inspired by the sedimentary layers of river deltas:
   earthy, sophisticated, timeless, grounded, resilient.
   ============================================================ */

:root {
  /* ---- Brand core (the six canonical delta hues) ---- */
  --delta-white:   #ffffff; /* Delta White   — pure ground */
  --river-sand:    #eae6e2; /* River Sand    — warm neutral */
  --alluvial-clay: #a5583f; /* Alluvial Clay — signature terracotta */
  --deep-silt:     #560000; /* Deep Silt     — deep maroon */
  --delta-green:   #043726; /* Delta Green   — forest deep (primary) */
  --estuary-blue:  #00012c; /* Estuary Blue  — near-black navy / ink */

  /* Warm paper — the default page ground */
  --paper: #fbfaf8;

  /* ---- Clay scale (terracotta accent · 500 canonical) ---- */
  --clay-50:  #f7ece7;
  --clay-100: #efd6cc;
  --clay-200: #ddb1a1;
  --clay-300: #cb9078;
  --clay-400: #ba6f53;
  --clay-500: #a5583f; /* ● Alluvial Clay */
  --clay-600: #8a4632;
  --clay-700: #6c3727;
  --clay-800: #4f291d;
  --clay-900: #341b13;

  /* ---- Green scale (Delta Green forest · 600 canonical, 900 = brand deep) ---- */
  --green-50:  #e9f1ec;
  --green-100: #c8ddd2;
  --green-200: #9bc0af;
  --green-300: #6a9c85;
  --green-400: #3d7b62;
  --green-500: #1d6147;
  --green-600: #0f5038; /* ● usable forest */
  --green-700: #0c4530;
  --green-800: #073a28;
  --green-900: #043726; /* brand Delta Green */

  /* ---- Silt scale (Deep Silt maroon · 700 canonical) ---- */
  --silt-50:  #f7e9e9;
  --silt-100: #eccccc;
  --silt-200: #dba8a8;
  --silt-300: #c06b6b;
  --silt-400: #a13c3c;
  --silt-500: #8a1f1f;
  --silt-600: #6e0d0d;
  --silt-700: #560000; /* ● Deep Silt */
  --silt-900: #380000;

  /* ---- Ink ramp (Estuary-blue neutrals) ---- */
  --ink-50:  #f2f1f4;
  --ink-100: #e3e3ea;
  --ink-200: #cacbd6;
  --ink-300: #a7a9bb;
  --ink-400: #7c7e96;
  --ink-500: #545674;
  --ink-600: #353855;
  --ink-700: #1e2046;
  --ink-800: #0c0e34;
  --ink-900: #00012c; /* Estuary Blue */

  /* ---- Estuary accent — a usable river blue for links / info ---- */
  --current-blue: #2f5f80;

  /* ============================================================
     Semantic aliases — reference these in product UI.
     ============================================================ */

  /* Text */
  --text-primary:     #16182f;  /* headlines, strong copy (ink) */
  --text-secondary:   #4a4d68;  /* paragraph / body copy */
  --text-muted:       #82849a;  /* captions, mono labels, placeholder */
  --text-accent:      var(--clay-600); /* eyebrows, terracotta emphasis */
  --text-on-dark:     rgba(255, 255, 255, 0.92);
  --text-on-dark-dim: rgba(255, 255, 255, 0.62);

  /* Surfaces */
  --surface-page:  var(--paper);
  --surface-card:  var(--delta-white);
  --surface-muted: #f4f0ea; /* warm sand well */

  /* Borders */
  --border-subtle:  #ece7e0;
  --border-default: #ddd6cc;
  --border-strong:  #c7bfb3;
  --border-on-dark: rgba(255, 255, 255, 0.16);

  /* Brand intent aliases */
  --brand-primary: var(--delta-green);   /* solid CTAs, dark bands */
  --brand-accent:  var(--alluvial-clay); /* warm highlight, eyebrows */

  /* Status / feedback (kept earthy, on-brand) */
  --success: var(--green-500);
  --warning: var(--clay-500);
  --danger:  var(--silt-600);
  --info:    var(--current-blue);
}