/* ============================================================
     AtelierBID — interactive product guide
     Fully self-contained: no external fonts, scripts, or assets.
     Aesthetic: editorial "atelier design-manual" — warm ivory paper,
     ink serif display, brand-blue + gold accents, dot-grid texture.
     Brand tokens ported from data/design-system.json.
     ============================================================ */

  :root {
    --paper:      #F6F1E7;
    --paper-2:    #FBF8F1;
    --paper-3:    #EFE8D9;
    --ink:        #1A1714;
    --ink-soft:   #4C463C;
    --label:      #6B6358;
    --rule:       #DED4C0;
    --rule-soft:  #E7DECC;
    --accent:     #2D6CDF;   /* brand accent */
    --accent-2:   #1E4FB0;
    --gold:       #C7911B;   /* deepened #F0B429 for contrast on paper */
    --gold-bright:#F0B429;
    --green:      #0D9488;   /* RAG positive */
    --red:        #D63031;   /* RAG negative */
    --neutral:    #9CA3AF;
    --violet:     #6B4FA8;

    --serif: "Palatino Linotype", "Book Antiqua", Cambria, Georgia, "Times New Roman", serif;
    --sans:  "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif;
    --mono:  "Cascadia Code", "Cascadia Mono", Consolas, "SFMono-Regular", Menlo, monospace;

    --maxw: 1120px;
    --shadow: 0 1px 2px rgba(26,23,20,.06), 0 10px 30px rgba(26,23,20,.08);
    --shadow-lg: 0 2px 6px rgba(26,23,20,.08), 0 24px 60px rgba(26,23,20,.14);
    --radius: 4px;
    --transition: .28s cubic-bezier(.2,.7,.2,1);
  }

  html[data-theme="dark"] {
    --paper:      #17130D;
    --paper-2:    #201A12;
    --paper-3:    #120F0A;
    --ink:        #F2E9D7;
    --ink-soft:   #C6BBA5;
    --label:      #A99C82;
    --rule:       #372E1E;
    --rule-soft:  #2A2318;
    --accent:     #6C9BFF;
    --accent-2:   #97B7FF;
    --gold:       #E8B94A;
    --gold-bright:#F0B429;
    --green:      #2FBFB0;
    --red:        #F0605F;
    --shadow: 0 1px 2px rgba(0,0,0,.4), 0 10px 30px rgba(0,0,0,.5);
    --shadow-lg: 0 2px 6px rgba(0,0,0,.5), 0 24px 60px rgba(0,0,0,.6);
  }

  * { box-sizing: border-box; }
  html { scroll-behavior: smooth; scroll-padding-top: 84px; }

  body {
    margin: 0;
    background-color: var(--paper);
    background-image:
      radial-gradient(circle at 1px 1px, var(--rule) 1px, transparent 0);
    background-size: 26px 26px;
    color: var(--ink);
    font-family: var(--sans);
    font-size: 17px;
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
  }

  ::selection { background: var(--gold-bright); color: #1A1714; }

  a { color: var(--accent); text-decoration: none; }
  a:hover { text-decoration: underline; text-underline-offset: 3px; }

  h1,h2,h3,h4 { font-family: var(--serif); font-weight: 600; line-height: 1.12; letter-spacing: -.01em; }

  .kicker {
    font-family: var(--sans);
    font-size: 12px; font-weight: 700;
    letter-spacing: .22em; text-transform: uppercase;
    color: var(--gold);
    display: inline-flex; align-items: center; gap: .6em;
  }
  .kicker::before { content: ""; width: 26px; height: 2px; background: var(--gold); display: inline-block; }

  .wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 28px; }

  /* ---------- top nav ---------- */
  header.nav {
    position: sticky; top: 0; z-index: 60;
    backdrop-filter: saturate(1.3) blur(10px);
    background: color-mix(in srgb, var(--paper) 82%, transparent);
    border-bottom: 1px solid var(--rule);
  }
  .nav-inner { max-width: var(--maxw); margin: 0 auto; padding: 12px 28px;
    display: flex; align-items: center; gap: 20px; }
  .brand { display: flex; align-items: baseline; gap: 10px; font-family: var(--serif);
    font-size: 22px; font-weight: 600; letter-spacing: -.01em; }
  .brand .mark {
    font-family: var(--sans); font-weight: 800; font-size: 13px; letter-spacing: .04em;
    color: var(--paper); background: var(--ink); padding: 3px 7px; border-radius: 3px;
    transform: translateY(-2px);
  }
  .brand small { font-family: var(--sans); font-size: 11px; letter-spacing: .12em;
    text-transform: uppercase; color: var(--label); font-weight: 600; }
  .nav-links { display: flex; gap: 4px; margin-left: auto; align-items: center; }
  .nav-links a {
    font-family: var(--sans); font-size: 13.5px; font-weight: 600; color: var(--ink-soft);
    padding: 7px 11px; border-radius: 3px; position: relative;
  }
  .nav-links a:hover { color: var(--ink); text-decoration: none; background: var(--paper-3); }
  .nav-links a.active { color: var(--accent); }
  .nav-links a.active::after {
    content: ""; position: absolute; left: 11px; right: 11px; bottom: 2px; height: 2px;
    background: var(--accent); border-radius: 2px;
  }
  .theme-toggle {
    margin-left: 8px; border: 1px solid var(--rule); background: var(--paper-2);
    color: var(--ink); font-family: var(--mono); font-size: 12px; cursor: pointer;
    padding: 7px 10px; border-radius: 3px; transition: var(--transition); white-space: nowrap;
  }
  .theme-toggle:hover { border-color: var(--accent); color: var(--accent); }
  @media (max-width: 860px) { .nav-links a:not(.cta) { display: none; } }

  /* ---------- hero ---------- */
  .hero { position: relative; overflow: hidden; padding: 76px 0 56px; }
  .hero::before {
    content: ""; position: absolute; top: -140px; right: -120px; width: 460px; height: 460px;
    background: radial-gradient(circle, color-mix(in srgb, var(--accent) 22%, transparent), transparent 62%);
    z-index: 0; pointer-events: none;
  }
  .hero::after {
    content: ""; position: absolute; bottom: -160px; left: -100px; width: 360px; height: 360px;
    background: radial-gradient(circle, color-mix(in srgb, var(--gold-bright) 20%, transparent), transparent 64%);
    z-index: 0; pointer-events: none;
  }
  .hero .wrap { position: relative; z-index: 1; }
  .hero h1 { font-size: clamp(40px, 6.4vw, 74px); margin: 18px 0 0; max-width: 15ch; }
  .hero h1 .em { font-style: italic; color: var(--accent); }
  .hero .lede { font-size: clamp(18px, 2.1vw, 22px); color: var(--ink-soft); max-width: 60ch;
    margin: 22px 0 0; line-height: 1.55; }
  .chips { display: flex; flex-wrap: wrap; gap: 10px; margin: 28px 0 0; }
  .chip {
    font-family: var(--sans); font-size: 13px; font-weight: 600; color: var(--ink);
    background: var(--paper-2); border: 1px solid var(--rule); border-radius: 100px;
    padding: 7px 14px; display: inline-flex; align-items: center; gap: 8px;
  }
  .chip .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--green); }
  .chip .dot.b { background: var(--accent); } .chip .dot.g { background: var(--gold-bright); }
  .chip .dot.r { background: var(--red); } .chip .dot.v { background: var(--violet); }
  .cta-row { display: flex; flex-wrap: wrap; gap: 14px; margin: 34px 0 0; }
  .btn {
    font-family: var(--sans); font-weight: 700; font-size: 15px; cursor: pointer;
    padding: 13px 22px; border-radius: 3px; border: 1px solid transparent; transition: var(--transition);
    display: inline-flex; align-items: center; gap: 9px;
  }
  .btn.primary { background: var(--ink); color: var(--paper); }
  .btn.primary:hover { background: var(--accent); text-decoration: none; transform: translateY(-1px); }
  .btn.ghost { background: transparent; color: var(--ink); border-color: var(--rule); }
  .btn.ghost:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
  .btn .arr { transition: transform var(--transition); }
  .btn:hover .arr { transform: translateX(4px); }

  .namespace-note {
    margin: 30px 0 0; font-size: 13.5px; color: var(--label); font-family: var(--sans);
    border-left: 2px solid var(--gold); padding: 4px 0 4px 14px; max-width: 68ch; line-height: 1.5;
  }
  .namespace-note code { font-family: var(--mono); font-size: 12.5px; color: var(--ink-soft); }

  /* ---------- sections ---------- */
  section.band { padding: 70px 0; border-top: 1px solid var(--rule); position: relative; }
  .sec-head { display: flex; align-items: baseline; gap: 18px; flex-wrap: wrap; margin-bottom: 6px; }
  .sec-num { font-family: var(--mono); font-size: 13px; color: var(--gold); font-weight: 700; }
  section h2 { font-size: clamp(28px, 4vw, 42px); margin: 12px 0 0; max-width: 20ch; }
  .sec-sub { color: var(--ink-soft); font-size: 18px; max-width: 64ch; margin: 18px 0 0; }

  /* ---------- capability tabs ---------- */
  .tabs { display: inline-flex; gap: 4px; margin: 34px 0 0; background: var(--paper-2);
    border: 1px solid var(--rule); border-radius: 100px; padding: 4px; }
  .tab-btn {
    font-family: var(--sans); font-size: 14px; font-weight: 700; cursor: pointer;
    border: none; background: transparent; color: var(--ink-soft); padding: 9px 18px;
    border-radius: 100px; transition: var(--transition);
  }
  .tab-btn[aria-selected="true"] { background: var(--ink); color: var(--paper); }
  .tab-panel { margin-top: 26px; }
  .tab-panel[hidden] { display: none; }

  .card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; }
  .cap-card {
    background: var(--paper-2); border: 1px solid var(--rule); border-radius: var(--radius);
    padding: 22px; position: relative; overflow: hidden; transition: var(--transition);
  }
  .cap-card::before { content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 3px;
    background: var(--accent); opacity: .0; transition: var(--transition); }
  .cap-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); border-color: var(--rule-soft); }
  .cap-card:hover::before { opacity: 1; }
  .cap-card .cmd { font-family: var(--mono); font-size: 13px; color: var(--accent); font-weight: 600; }
  .cap-card h4 { font-size: 20px; margin: 10px 0 8px; }
  .cap-card p { margin: 0; font-size: 14.5px; color: var(--ink-soft); line-height: 1.55; }
  .cap-card .out { margin: 14px 0 0; font-family: var(--mono); font-size: 12px; color: var(--label); }
  .cap-card .out b { color: var(--ink-soft); font-weight: 600; }
  .badge { display: inline-block; font-family: var(--sans); font-size: 10.5px; font-weight: 800;
    letter-spacing: .1em; text-transform: uppercase; padding: 3px 8px; border-radius: 3px;
    background: color-mix(in srgb, var(--accent) 14%, transparent); color: var(--accent-2); margin-left: 8px; }
  .badge.ref { background: color-mix(in srgb, var(--gold-bright) 24%, transparent); color: var(--gold); }

  .phase-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px,1fr)); gap: 16px; }
  .phase-item { background: var(--paper-2); border: 1px solid var(--rule); border-radius: var(--radius); padding: 20px; }
  .phase-item .ph { font-family: var(--mono); font-size: 12px; color: var(--gold); font-weight: 700; letter-spacing: .08em; }
  .phase-item h4 { font-size: 18px; margin: 8px 0 6px; }
  .phase-item p { margin: 0 0 12px; font-size: 14px; color: var(--ink-soft); }
  .phase-item ul { margin: 0; padding-left: 0; list-style: none; display: flex; flex-wrap: wrap; gap: 6px; }
  .phase-item li { font-family: var(--mono); font-size: 11.5px; color: var(--ink-soft);
    background: var(--paper-3); border: 1px solid var(--rule-soft); border-radius: 3px; padding: 3px 7px; }

  /* ---------- architecture ---------- */
  .arch { display: grid; grid-template-columns: 1.15fr .85fr; gap: 40px; align-items: center; margin-top: 34px; }
  @media (max-width: 900px) { .arch { grid-template-columns: 1fr; } }
  .arch svg { width: 100%; height: auto; display: block; }
  .arch-points { display: grid; gap: 18px; }
  .arch-point { display: flex; gap: 14px; align-items: flex-start; }
  .arch-point .n { flex: none; width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center;
    font-family: var(--mono); font-size: 13px; font-weight: 700; color: var(--paper); background: var(--ink); }
  .arch-point h4 { font-size: 17px; margin: 2px 0 4px; font-family: var(--sans); font-weight: 700; }
  .arch-point p { margin: 0; font-size: 14.5px; color: var(--ink-soft); }
  .arch-point code { font-family: var(--mono); font-size: 12.5px; color: var(--accent); }

  .scan { margin-top: 40px; display: grid; grid-template-columns: repeat(4,1fr); gap: 14px; }
  @media (max-width: 720px){ .scan { grid-template-columns: repeat(2,1fr);} }
  .scan-cell { border: 1px solid var(--rule); border-radius: var(--radius); padding: 18px; background: var(--paper-2); }
  .scan-cell .l { font-family: var(--serif); font-size: 34px; font-weight: 700; line-height: 1; }
  .scan-cell.s .l{color:var(--accent);} .scan-cell.c .l{color:var(--gold);}
  .scan-cell.a .l{color:var(--green);} .scan-cell.n .l{color:var(--violet);}
  .scan-cell h4 { font-family: var(--sans); font-size: 15px; margin: 10px 0 5px; }
  .scan-cell p { margin: 0; font-size: 13px; color: var(--ink-soft); }

  /* ---------- stepper (centrepiece) ---------- */
  .demo-scenario {
    margin: 30px 0 8px; background: var(--paper-2); border: 1px solid var(--rule);
    border-left: 3px solid var(--accent); border-radius: var(--radius); padding: 20px 24px;
    font-size: 15.5px; color: var(--ink-soft); max-width: 78ch;
  }
  .demo-scenario b { color: var(--ink); }
  .stepper { display: grid; grid-template-columns: 260px 1fr; gap: 34px; margin-top: 30px; }
  @media (max-width: 900px) { .stepper { grid-template-columns: 1fr; } }
  .rail { position: relative; }
  .rail ol { list-style: none; margin: 0; padding: 0; position: relative; }
  .rail::before { content:""; position:absolute; left: 15px; top: 12px; bottom: 12px; width: 2px; background: var(--rule); }
  html[data-theme="dark"] .rail::before { background: var(--rule); }
  .rail li { position: relative; padding: 0 0 4px 44px; margin-bottom: 6px; cursor: pointer; }
  .rail li .rn {
    position: absolute; left: 0; top: 0; width: 32px; height: 32px; border-radius: 50%;
    display: grid; place-items: center; font-family: var(--mono); font-size: 13px; font-weight: 700;
    background: var(--paper); color: var(--label); border: 2px solid var(--rule); transition: var(--transition); z-index: 1;
  }
  .rail li .rt { font-family: var(--sans); font-size: 14px; font-weight: 600; color: var(--ink-soft);
    padding: 6px 0; transition: var(--transition); }
  .rail li .rp { font-family: var(--mono); font-size: 10.5px; color: var(--gold); letter-spacing: .06em; display:block; }
  .rail li:hover .rt { color: var(--ink); }
  .rail li.active .rn { background: var(--accent); color: #fff; border-color: var(--accent); box-shadow: 0 0 0 5px color-mix(in srgb, var(--accent) 18%, transparent); }
  .rail li.active .rt { color: var(--ink); }
  .rail li.done .rn { background: var(--ink); color: var(--paper); border-color: var(--ink); }

  .stage {
    background: var(--paper-2); border: 1px solid var(--rule); border-radius: var(--radius);
    box-shadow: var(--shadow); overflow: hidden; min-height: 420px; display: flex; flex-direction: column;
  }
  .stage-top { padding: 24px 26px 0; }
  .stage-ph { font-family: var(--mono); font-size: 12px; color: var(--gold); font-weight: 700; letter-spacing: .1em; }
  .stage h3 { font-size: 26px; margin: 8px 0 0; }
  .stage .desc { color: var(--ink-soft); font-size: 15.5px; margin: 12px 0 0; }
  .stage-body { padding: 20px 26px 26px; }
  .kv { display: grid; grid-template-columns: auto 1fr; gap: 10px 16px; margin: 18px 0 0; align-items: start; }
  .kv .k { font-family: var(--sans); font-size: 11px; font-weight: 800; letter-spacing: .12em; text-transform: uppercase;
    color: var(--label); padding-top: 3px; white-space: nowrap; }
  .kv .v { font-size: 14.5px; color: var(--ink-soft); }
  .kv .v.mono { font-family: var(--mono); font-size: 12.5px; color: var(--ink); }

  .cmd-block {
    display: flex; align-items: center; gap: 12px; margin: 20px 0 0;
    background: var(--paper-3); border: 1px solid var(--rule); border-radius: var(--radius);
    padding: 12px 14px; font-family: var(--mono); font-size: 13.5px; color: var(--ink);
    overflow-x: auto;
  }
  html[data-theme="dark"] .cmd-block { background: #0d0b07; }
  .cmd-block .prompt { color: var(--green); user-select: none; }
  .cmd-block code { white-space: nowrap; }
  .copy-btn { margin-left: auto; flex: none; font-family: var(--sans); font-size: 12px; font-weight: 700;
    cursor: pointer; border: 1px solid var(--rule); background: var(--paper-2); color: var(--ink-soft);
    border-radius: 3px; padding: 6px 11px; transition: var(--transition); }
  .copy-btn:hover { border-color: var(--accent); color: var(--accent); }
  .copy-btn.copied { border-color: var(--green); color: var(--green); }

  .stage-nav { margin-top: auto; display: flex; justify-content: space-between; align-items: center;
    padding: 16px 26px; border-top: 1px solid var(--rule); background: var(--paper); }
  .stage-nav .prog { font-family: var(--mono); font-size: 12px; color: var(--label); }
  .stage-nav .sp { display: flex; gap: 10px; }
  .mini-btn { font-family: var(--sans); font-weight: 700; font-size: 13.5px; cursor: pointer;
    border: 1px solid var(--rule); background: var(--paper-2); color: var(--ink); border-radius: 3px;
    padding: 8px 15px; transition: var(--transition); }
  .mini-btn:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
  .mini-btn:disabled { opacity: .4; cursor: not-allowed; }
  .mini-btn.solid { background: var(--ink); color: var(--paper); border-color: var(--ink); }
  .mini-btn.solid:hover:not(:disabled) { background: var(--accent); border-color: var(--accent); color:#fff; }

  .fade { animation: fade .4s ease both; }
  @keyframes fade { from { opacity: 0; transform: translateY(6px);} to {opacity:1; transform:none;} }

  /* ---------- result mockup ---------- */
  .result { margin-top: 40px; }
  .result-frame { background: var(--paper-2); border: 1px solid var(--rule); border-radius: var(--radius);
    box-shadow: var(--shadow-lg); padding: 8px; }
  .result-frame svg { width: 100%; height: auto; display: block; border-radius: 2px; }
  .result-cap { font-family: var(--sans); font-size: 13px; color: var(--label); margin: 14px 0 0; text-align: center; }
  .result-cap code { font-family: var(--mono); color: var(--ink-soft); }

  /* ---------- reference ---------- */
  .ref-controls { display:flex; gap: 14px; align-items:center; flex-wrap: wrap; margin: 30px 0 20px; }
  .search { flex: 1; min-width: 240px; position: relative; }
  .search input {
    width: 100%; font-family: var(--sans); font-size: 15px; color: var(--ink);
    background: var(--paper-2); border: 1px solid var(--rule); border-radius: 3px;
    padding: 12px 14px 12px 40px; transition: var(--transition);
  }
  .search input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 14%, transparent); }
  .search svg { position: absolute; left: 13px; top: 50%; transform: translateY(-50%); opacity: .5; }
  .ref-count { font-family: var(--mono); font-size: 13px; color: var(--label); }

  .ref-group { margin: 26px 0 0; }
  .ref-group > h4 { font-family: var(--sans); font-size: 13px; font-weight: 800; letter-spacing: .12em;
    text-transform: uppercase; color: var(--gold); margin: 0 0 12px; display: flex; align-items:center; gap: 10px; }
  .ref-group > h4 .ct { color: var(--label); font-weight: 700; letter-spacing: 0; }
  .ref-row { display: grid; grid-template-columns: minmax(230px, 320px) 1fr; gap: 8px 24px;
    padding: 12px 4px; border-top: 1px solid var(--rule-soft); align-items: baseline; }
  .ref-row .name { font-family: var(--mono); font-size: 13.5px; color: var(--accent); font-weight: 600; }
  .ref-row .name .k { color: var(--label); font-size: 10px; font-weight:800; letter-spacing:.08em; text-transform:uppercase;
    margin-left: 8px; background: var(--paper-3); padding: 2px 6px; border-radius: 3px; }
  .ref-row .desc { font-size: 14px; color: var(--ink-soft); }
  .ref-empty { font-family: var(--sans); color: var(--label); padding: 24px 4px; font-style: italic; }

  .install { margin-top: 40px; background: var(--paper-2); border: 1px solid var(--rule);
    border-radius: var(--radius); padding: 26px; }
  .install h3 { font-size: 22px; margin: 0 0 4px; }
  .install p { color: var(--ink-soft); font-size: 14.5px; margin: 6px 0 0; }

  /* ---------- footer ---------- */
  footer { border-top: 1px solid var(--rule); padding: 46px 0 60px; margin-top: 20px; }
  .foot { display: flex; justify-content: space-between; gap: 24px; flex-wrap: wrap; align-items: flex-start; }
  .foot .fb { font-family: var(--serif); font-size: 24px; }
  .foot p { color: var(--label); font-size: 13.5px; margin: 8px 0 0; max-width: 52ch; line-height: 1.6; }
  .foot .links { display: flex; flex-direction: column; gap: 7px; font-size: 14px; }
  .foot .links a { color: var(--ink-soft); font-weight: 600; }

  .reveal { opacity: 0; transform: translateY(18px); transition: opacity .7s ease, transform .7s cubic-bezier(.2,.7,.2,1); }
  .reveal.in { opacity: 1; transform: none; }
  @media (prefers-reduced-motion: reduce) {
    * { scroll-behavior: auto !important; }
    .reveal { opacity: 1; transform: none; transition: none; }
    .fade { animation: none; }
  }