:root {
  --chassis: #12100c;
  --panel: #1b1812;
  --inset: #0e0d0a;
  --rail: #16130f;
  --line: rgba(232, 184, 74, 0.14);
  --line-soft: rgba(243, 239, 228, 0.08);
  --ink: #f3efe4;
  --ink-2: #c8c0ae;
  --mute: #8a8376;
  --gold: #e8b84a;
  --gold-hot: #f3c96a;
  --teal: #3db8b0;
  --ok: #7dce8a;
  --bad: #e26a4a;
  --warn: #e0a24a;
  --font: "IBM Plex Sans", "Noto Sans SC", "PingFang SC", sans-serif;
  --display: "Syne", "Noto Sans SC", sans-serif;
  --mono: "IBM Plex Mono", "SFMono-Regular", ui-monospace, Menlo, monospace;
  --rail-w: 268px;
  --top-h: 58px;
  --radius: 10px;
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--chassis);
  line-height: 1.5;
}
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
a { color: var(--teal); text-decoration: none; }
a:hover { color: #5ad0c8; }
:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 2px;
}
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0); border: 0;
}
[hidden] { display: none !important; }

.app {
  display: flex;
  height: 100%;
  min-height: 100dvh;
}

/* ----- rail ----- */
.rail {
  width: var(--rail-w);
  flex-shrink: 0;
  background: var(--rail);
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  min-height: 0;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 16px 16px 12px;
  color: var(--ink);
}
.brand:hover { color: var(--ink); }
.brand-mark { width: 30px; height: 30px; color: #fff; flex-shrink: 0; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-text em {
  font-family: var(--display);
  font-style: normal;
  font-weight: 800;
  letter-spacing: 0.12em;
  font-size: 1.05rem;
}
.brand-text small {
  color: var(--gold);
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.22em;
  margin-top: 3px;
}
.finder { display: block; padding: 0 12px 12px; }
.finder input {
  width: 100%;
  background: var(--inset);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 8px 10px;
  color: var(--ink);
}
.finder input::placeholder { color: var(--mute); }
.cats {
  overflow: auto;
  padding: 0 8px 20px;
  flex: 1;
}
.cat { margin: 0 0 14px; }
.cat h2 {
  margin: 0 8px 6px;
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--gold);
  font-weight: 600;
}
.cat a {
  display: block;
  padding: 6px 8px;
  border-radius: 6px;
  color: var(--ink-2);
  font-size: 13px;
}
.cat a:hover { background: rgba(232, 184, 74, 0.08); color: var(--ink); }
.cat a.active {
  background: rgba(61, 184, 176, 0.16);
  color: var(--teal);
}
.cat a .hint {
  display: block;
  font-size: 11px;
  color: var(--mute);
}

/* ----- stage ----- */
.stage {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  background:
    radial-gradient(1200px 400px at 80% -10%, rgba(232, 184, 74, 0.07), transparent 50%),
    var(--chassis);
}
.topbar {
  height: var(--top-h);
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 0 20px;
}
.crumb { min-width: 0; }
.crumb-cat {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--teal);
}
.crumb-sep { margin: 0 8px; color: var(--mute); }
.topbar h1 {
  display: inline;
  margin: 0;
  font-size: 1.15rem;
  font-weight: 600;
}
.pledge {
  margin: 0 0 0 auto;
  color: var(--mute);
  font-size: 12px;
  white-space: nowrap;
}
.trace {
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--gold) 20%, var(--teal) 80%, transparent);
  opacity: 0.55;
  transform-origin: left;
}
.trace.ok { background: linear-gradient(90deg, transparent, var(--ok), transparent); }
.trace.bad { background: linear-gradient(90deg, transparent, var(--bad), transparent); }

.workspace {
  flex: 1;
  min-height: 0;
  padding: 14px 18px 18px;
  overflow: auto;
}

.rail-toggle {
  display: none;
  width: 36px;
  height: 36px;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 8px;
  flex-direction: column;
  justify-content: space-between;
}
.rail-toggle span { display: block; height: 1.5px; background: var(--ink); }

/* ----- tool chrome ----- */
.toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin-bottom: 10px;
}
.btn {
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--ink);
  padding: 7px 12px;
  border-radius: 7px;
  font-size: 13px;
}
.btn:hover { border-color: var(--gold); }
.btn.primary { background: var(--gold); color: #1a1408; border-color: var(--gold); font-weight: 600; }
.btn.primary:hover { background: var(--gold-hot); }
.btn.ghost { background: transparent; }
.btn.danger { color: var(--bad); }
.opt {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--ink-2);
  font-size: 13px;
}
.opt select, .field input, .field select, .field textarea {
  background: var(--inset);
  border: 1px solid var(--line);
  border-radius: 7px;
  padding: 7px 10px;
}
.field { display: flex; flex-direction: column; gap: 6px; }
.field label { font-size: 12px; color: var(--mute); }
.row { display: flex; gap: 10px; flex-wrap: wrap; }
.row > .field { flex: 1; min-width: 160px; }

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  min-height: calc(100dvh - 150px);
}
.split.stack { grid-template-columns: 1fr; min-height: 0; }
.pane {
  display: flex;
  flex-direction: column;
  min-height: 0;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.pane-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  border-bottom: 1px solid var(--line-soft);
  color: var(--mute);
  font-size: 12px;
  letter-spacing: 0.06em;
}
.editor, .out {
  flex: 1;
  min-height: 280px;
  width: 100%;
  border: 0;
  background: var(--inset);
  color: var(--ink);
  padding: 12px 14px;
  resize: none;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.55;
  tab-size: 2;
}
.out { overflow: auto; white-space: pre-wrap; word-break: break-word; }
.out.mono { white-space: pre; }

.status {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 10px;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--mute);
}
.status b { color: var(--ink-2); font-weight: 500; }
.status .ok { color: var(--ok); }
.status .bad { color: var(--bad); }

.tree { padding: 10px 14px 16px; overflow: auto; font-family: var(--mono); font-size: 13px; }
.tree details { margin-left: 14px; }
.tree > details { margin-left: 0; }
.tree summary { cursor: pointer; color: var(--ink-2); }
.tree .k { color: #8fd4cf; }
.tree .s { color: #e8c56a; }
.tree .n { color: #d98b6a; }
.tree .b { color: #9aa7e8; }
.tree .nil { color: var(--mute); }

.hl-key { color: #8fd4cf; }
.hl-str { color: #e8c56a; }
.hl-num { color: #d98b6a; }
.hl-kw { color: #9aa7e8; }

.tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 10px;
}
.tabs button {
  background: transparent;
  border: 0;
  border-bottom: 2px solid transparent;
  color: var(--mute);
  padding: 6px 10px;
}
.tabs button.active { color: var(--gold); border-bottom-color: var(--gold); }

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 12px;
}
.tool-card {
  display: block;
  padding: 16px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
}
.tool-card:hover { border-color: var(--gold); color: var(--ink); }
.tool-card small { display: block; margin-top: 6px; color: var(--mute); font-size: 12px; }

.preview-img {
  max-width: 100%;
  max-height: 280px;
  display: block;
  margin-top: 10px;
  background: repeating-conic-gradient(#2a261c 0% 25%, #1b1812 0% 50%) 0 0 / 16px 16px;
}
.qr-box { padding: 16px; background: #fff; display: inline-block; border-radius: 8px; }
.qr-box canvas { display: block; }

.table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
.table th, .table td {
  text-align: left;
  padding: 7px 8px;
  border-bottom: 1px solid var(--line-soft);
}
.table th { color: var(--mute); font-weight: 500; }

.note {
  color: var(--mute);
  font-size: 13px;
  margin: 0 0 10px;
}
.err {
  background: rgba(226, 106, 74, 0.12);
  border: 1px solid rgba(226, 106, 74, 0.35);
  color: #f0b2a2;
  padding: 8px 12px;
  border-radius: 8px;
  font-family: var(--mono);
  font-size: 12px;
  margin-bottom: 10px;
  white-space: pre-wrap;
}

.toast {
  position: fixed;
  bottom: 22px;
  right: 22px;
  background: var(--gold);
  color: #1a1408;
  padding: 10px 14px;
  border-radius: 8px;
  font-weight: 600;
  z-index: 50;
}

@media (max-width: 900px) {
  .rail {
    position: fixed;
    inset: 0 auto 0 0;
    z-index: 20;
    transform: translateX(-105%);
    transition: transform 0.2s ease;
  }
  body.rail-open .rail { transform: none; }
  .rail-toggle { display: flex; }
  .pledge { display: none; }
  .split { grid-template-columns: 1fr; min-height: 0; }
  .editor, .out { min-height: 220px; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}