:root {
  --bg: #14161a;
  --panel: #1d2026;
  --panel2: #23272f;
  --border: #31363f;
  --text: #d6dae2;
  --muted: #8b93a1;
  --accent: #e8a33d;
  --accent2: #4dd0e1;
  --good: #6fbf73;
  --warn: #e57373;
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}

* { box-sizing: border-box; }

html, body, #root {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
}

.app {
  display: flex;
  flex-direction: column;
  height: 100vh;
}

.topbar {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}

.topbar h1 {
  font-size: 16px;
  margin: 0 12px 0 0;
  font-weight: 600;
  color: var(--accent);
  white-space: nowrap;
}

button {
  background: var(--panel2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 14px;
  font-size: 13px;
  cursor: pointer;
}
button:hover { border-color: var(--muted); }
button:disabled { opacity: 0.45; cursor: default; }
button.primary {
  background: var(--accent);
  color: #1a1204;
  border-color: var(--accent);
  font-weight: 600;
}
button.play {
  background: var(--good);
  color: #06210a;
  border-color: var(--good);
  font-weight: 600;
}
button.play.preview {
  background: transparent;
  color: var(--accent);
  border-color: var(--accent);
}
button.loop.active {
  background: var(--accent2);
  color: #062a2f;
  border-color: var(--accent2);
  font-weight: 600;
}
button.code { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }
button.code.active { border-color: var(--accent2); color: var(--accent2); }

.status {
  margin-left: auto;
  font-size: 12px;
  color: var(--muted);
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 180px;
  justify-content: flex-end;
}

.badge {
  font-size: 11px;
  border-radius: 10px;
  padding: 2px 8px;
  border: 1px solid var(--border);
}
.badge.preview { color: var(--accent); border-color: var(--accent); }
.badge.full { color: var(--good); border-color: var(--good); }
.badge.err { color: var(--warn); border-color: var(--warn); }

.progressbar {
  width: 90px;
  height: 6px;
  background: var(--panel2);
  border-radius: 3px;
  overflow: hidden;
}
.progressbar > div {
  height: 100%;
  background: var(--accent2);
  transition: width 0.1s linear;
}

.main {
  display: flex;
  flex: 1;
  min-height: 0;
}

.sidebar {
  width: 340px;
  min-width: 340px;
  overflow-y: auto;
  background: var(--panel);
  border-right: 1px solid var(--border);
  padding: 8px;
}

.content {
  flex: 1;
  overflow-y: auto;
  padding: 10px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  align-content: start;
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 10px 10px;
  min-width: 0;
}
.card.wide { grid-column: 1 / -1; }
.card h2 {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  margin: 0 0 6px;
  font-weight: 600;
}
.card canvas { display: block; width: 100%; }

.scene3d { height: 380px; position: relative; }
.scene3d canvas { height: 100%; border-radius: 6px; }
.scene-hint {
  position: absolute;
  bottom: 10px;
  right: 14px;
  font-size: 11px;
  color: var(--muted);
  pointer-events: none;
}

/* Parameter panel */
details.group {
  border: 1px solid var(--border);
  border-radius: 6px;
  margin-bottom: 6px;
  background: var(--panel2);
}
details.group summary {
  cursor: pointer;
  padding: 6px 10px;
  font-size: 13px;
  font-weight: 600;
  user-select: none;
}
details.group[open] summary { border-bottom: 1px solid var(--border); }
.group-body { padding: 6px 10px 8px; }

.param-row { margin-bottom: 8px; }
.param-label {
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  margin-bottom: 2px;
  align-items: baseline;
}
.param-label .name { color: var(--text); }
.param-controls { display: flex; gap: 8px; align-items: center; }
.param-controls input[type='range'] { flex: 1; accent-color: var(--accent2); }
.param-controls input[type='number'] {
  width: 88px;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 3px 5px;
  font-size: 12px;
}
.param-controls select, .param-controls input[type='checkbox'] {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 12px;
}
.param-help { font-size: 11px; color: var(--muted); margin-top: 1px; }

/* Diagnostics */
.diag table { border-collapse: collapse; font-size: 12px; width: 100%; }
.diag td, .diag th {
  padding: 2px 8px 2px 0;
  text-align: left;
  color: var(--text);
  font-weight: 400;
}
.diag th { color: var(--muted); white-space: nowrap; }
.diag .partials { font-variant-numeric: tabular-nums; }
.warning { color: var(--warn); font-size: 12px; margin-top: 4px; }
.cachenote { color: var(--muted); font-size: 11px; margin-top: 6px; }

.mode-list { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 6px; }
.mode-list button { padding: 3px 10px; font-size: 12px; }
.mode-list button.active { border-color: var(--accent2); color: var(--accent2); }

/* Code panel */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(8, 10, 13, 0.72);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 50;
}

.code-panel {
  width: min(1180px, 94vw);
  height: min(860px, 92vh);
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.code-header {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border-bottom: 1px solid var(--border);
}
.code-header h2 {
  margin: 0;
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
}
.code-header button:last-child { margin-left: 0; }
.code-note {
  font-size: 11.5px;
  color: var(--muted);
  margin-right: auto;
}

.code-body { display: flex; flex: 1; min-height: 0; }

.code-files {
  width: 236px;
  min-width: 236px;
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 6px;
}
.code-files button {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 6px;
  width: 100%;
  text-align: left;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 5px;
  padding: 5px 8px;
  margin-bottom: 2px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 12px;
}
.code-files button:hover { background: var(--panel2); }
.code-files button.active {
  background: var(--panel2);
  border-color: var(--accent2);
  color: var(--accent2);
}
.code-files .fname { display: flex; align-items: center; gap: 5px; }
.code-files .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
}
.code-files .ftag {
  font-size: 9.5px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-family: system-ui, sans-serif;
}

.code-main { flex: 1; min-width: 0; display: flex; flex-direction: column; }
.code-toolbar {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 10px;
  border-bottom: 1px solid var(--border);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 12px;
  color: var(--text);
}
.code-hint {
  font-size: 11px;
  color: var(--muted);
  font-family: system-ui, sans-serif;
}
.code-editor { flex: 1; min-height: 0; overflow: hidden; }

.code-error {
  border-top: 1px solid var(--warn);
  background: #2a1a1a;
  color: #ffb4a9;
  padding: 7px 12px;
  font-size: 12px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
}

.error-card { border-color: var(--warn); }
.error-card h2 { color: var(--warn); }
.error-card div { font-size: 12px; }
.error-card strong { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }

@media (max-width: 1100px) {
  .content { grid-template-columns: 1fr; }
}

/* Sidebar credit */
.sidebar-credit {
  margin-top: 10px;
  padding: 8px 10px 12px;
  border-top: 1px solid var(--border);
  font-size: 11px;
  line-height: 1.5;
  color: var(--muted);
}
.sidebar-credit a { color: var(--accent2); }
button.linklike {
  background: none;
  border: none;
  padding: 0;
  margin-top: 4px;
  font-size: 11.5px;
  color: var(--accent);
  cursor: pointer;
}
button.linklike:hover { text-decoration: underline; border: none; }

/* Tutorial */
.tut-loading {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
}

.tutorial {
  flex: 1;
  min-height: 0;
  display: flex;
  overflow-y: auto;
  scroll-behavior: smooth;
  background: var(--bg);
}

.tut-toc {
  position: sticky;
  top: 0;
  align-self: flex-start;
  width: 230px;
  min-width: 230px;
  padding: 26px 8px 16px 16px;
  display: none;
  flex-direction: column;
  gap: 2px;
}
@media (min-width: 1050px) {
  .tut-toc { display: flex; }
}
.tut-toc-head {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 8px;
}
.tut-toc a {
  color: var(--muted);
  text-decoration: none;
  font-size: 12.5px;
  padding: 3px 6px;
  border-radius: 4px;
}
.tut-toc a:hover { color: var(--text); background: var(--panel2); }
.tut-toc button { margin-top: 14px; font-size: 12px; }

.tut-body {
  flex: 1;
  max-width: 860px;
  padding: 24px 28px 80px;
  font-size: 14.5px;
  line-height: 1.65;
}
.tut-body section { scroll-margin-top: 14px; }
.tut-header h1 {
  font-size: 26px;
  margin: 6px 0 12px;
  color: var(--accent);
}
.tut-lede {
  font-size: 15px;
  color: var(--text);
}
.tut-body h2 {
  font-size: 19px;
  margin: 40px 0 10px;
  color: var(--accent);
  border-bottom: 1px solid var(--border);
  padding-bottom: 6px;
}
.tut-body p { margin: 10px 0; }
.tut-body a { color: var(--accent2); }
.tut-body code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.92em;
  background: var(--panel2);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0 4px;
}

.tut-eq {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 14px 0;
  overflow-x: auto;
  padding: 4px 2px;
}
.tut-eq-body { flex: 1; text-align: center; }
.tut-eq-tag { color: var(--muted); font-size: 13px; white-space: nowrap; }
.tut-eq .katex { font-size: 1.02em; }

.tut-fig {
  margin: 18px 0;
  padding: 10px 12px 12px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 8px;
}
.tut-fig canvas { display: block; width: 100%; border-radius: 4px; }
.tut-fig figcaption {
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--muted);
  margin-top: 8px;
}
.tut-fig figcaption i, .tut-fig figcaption b { color: var(--text); }

.tut-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 22px;
  align-items: center;
  margin-top: 8px;
}
.tut-controls button { font-size: 12px; padding: 4px 10px; }
.tut-controls button.tut-active { border-color: var(--accent2); color: var(--accent2); }
.tut-slider {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--muted);
}
.tut-slider input[type='range'] { width: 150px; accent-color: var(--accent2); }
.tut-slider-name { white-space: nowrap; }
.tut-slider-val {
  color: var(--text);
  font-variant-numeric: tabular-nums;
  min-width: 62px;
}

.tut-pipe {
  width: 100%;
  height: auto;
  margin: 10px 0;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 8px;
}

.tut-steps { padding-left: 22px; }
.tut-steps li { margin: 7px 0; }
.tut-list { padding-left: 22px; }
.tut-list li { margin: 9px 0; }
.tut-refs { padding-left: 22px; font-size: 13.5px; }
.tut-refs li { margin: 8px 0; }

/* Strike picker */
.strike-picker { position: relative; }
.strike-picker canvas { display: block; width: 100%; }
.picker-hint {
  font-size: 11px;
  color: var(--muted);
  text-align: right;
  margin-top: 2px;
}

.preset-row {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px 4px;
}
.preset-row label {
  font-size: 12px;
  color: var(--muted, #888);
}
.preset-row select {
  flex: 1;
  min-width: 0;
}
.preset-note {
  padding: 2px 10px 8px;
  font-size: 11.5px;
  line-height: 1.45;
  color: var(--muted, #888);
}