:root {
  --bg: #ffffff;
  --bg-subtle: #f6f8fa;
  --bg-card: #ffffff;
  --text: #1c2128;
  --text-muted: #57606a;
  --border: #d0d7de;
  --accent: #1f6feb;
  --accent-text: #ffffff;
  --code-bg: #f6f8fa;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.06), 0 1px 8px rgba(0, 0, 0, 0.04);

  --status-done-bg: #dafbe1;
  --status-done-text: #116329;
  --status-partial-bg: #fff8c5;
  --status-partial-text: #7d5b00;
  --status-verified-bg: #ddf4ff;
  --status-verified-text: #0349b4;
  --status-notstarted-bg: #eaeef2;
  --status-notstarted-text: #57606a;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1117;
    --bg-subtle: #161b22;
    --bg-card: #161b22;
    --text: #e6edf3;
    --text-muted: #9198a1;
    --border: #30363d;
    --accent: #4493f8;
    --accent-text: #0d1117;
    --code-bg: #010409;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 1px 8px rgba(0, 0, 0, 0.3);

    --status-done-bg: #113221;
    --status-done-text: #3fb950;
    --status-partial-bg: #3b2f00;
    --status-partial-text: #e3b341;
    --status-verified-bg: #0c2d6b;
    --status-verified-text: #79c0ff;
    --status-notstarted-bg: #21262d;
    --status-notstarted-text: #9198a1;
  }
}

:root[data-theme="dark"] {
  --bg: #0d1117;
  --bg-subtle: #161b22;
  --bg-card: #161b22;
  --text: #e6edf3;
  --text-muted: #9198a1;
  --border: #30363d;
  --accent: #4493f8;
  --accent-text: #0d1117;
  --code-bg: #010409;
}
:root[data-theme="light"] {
  --bg: #ffffff;
  --bg-subtle: #f6f8fa;
  --bg-card: #ffffff;
  --text: #1c2128;
  --text-muted: #57606a;
  --border: #d0d7de;
  --accent: #1f6feb;
  --accent-text: #ffffff;
  --code-bg: #f6f8fa;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  max-width: 100%;
  overflow-x: hidden;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.55;
}

code {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  background: var(--code-bg);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  font-size: 0.9em;
}

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 20px;
}

.hero {
  background: var(--bg-subtle);
  border-bottom: 1px solid var(--border);
  padding: 56px 0 40px;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent);
  margin: 0 0 10px;
}

h1 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  margin: 0 0 16px;
}

.pitch {
  max-width: 720px;
  color: var(--text-muted);
  font-size: 1.05rem;
}

.hero-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.btn {
  display: inline-block;
  padding: 8px 16px;
  border-radius: 6px;
  border: 1px solid var(--border);
  color: var(--text);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
  background: var(--bg-card);
  cursor: pointer;
}
.btn:hover { border-color: var(--accent); }
.btn-primary {
  background: var(--accent);
  color: var(--accent-text);
  border-color: var(--accent);
}

.tabbar {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}
.tabbar-inner {
  display: flex;
  gap: 4px;
  overflow-x: auto;
}
.tabbar a {
  display: inline-block;
  padding: 12px 14px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
}
.tabbar a:hover {
  color: var(--text);
  border-bottom-color: var(--accent);
}

.section {
  padding: 48px 0;
  border-bottom: 1px solid var(--border);
  scroll-margin-top: 52px;
}
.section:last-of-type { border-bottom: none; }

.section h2 {
  margin: 0 0 8px;
  font-size: 1.5rem;
}

.section-note {
  color: var(--text-muted);
  font-size: 0.92rem;
  max-width: 700px;
  margin: 0 0 24px;
}

.diagram-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  overflow-x: auto;
  box-shadow: var(--shadow);
}
.diagram-card .mermaid { display: flex; justify-content: center; }
.diagram-card svg { max-width: 100%; height: auto; }

/* --- Replay widget --- */
.replay-widget {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 20px;
}
@media (max-width: 720px) {
  .replay-widget { grid-template-columns: 1fr; }
}

.replay-picker {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
@media (max-width: 720px) {
  .replay-picker { flex-direction: row; flex-wrap: wrap; }
}

.replay-picker button {
  text-align: left;
  padding: 8px 12px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text);
  cursor: pointer;
  font-size: 0.88rem;
  text-transform: capitalize;
}
.replay-picker button.active {
  background: var(--accent);
  color: var(--accent-text);
  border-color: var(--accent);
}

.replay-viewer {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  box-shadow: var(--shadow);
  min-width: 0;
}

.replay-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}
.replay-description {
  color: var(--text-muted);
  font-size: 0.92rem;
}

.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: capitalize;
  background: var(--status-verified-bg);
  color: var(--status-verified-text);
}

.step-card {
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 16px;
  margin-bottom: 14px;
}
.step-card .step-label {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  font-weight: 600;
  margin-bottom: 2px;
}
.step-card .step-thought { margin: 0 0 10px; }
.step-card .step-action {
  font-family: ui-monospace, SFMono-Regular, monospace;
  font-size: 0.85rem;
  margin: 0 0 8px;
}
.step-card pre {
  background: var(--code-bg);
  border-radius: 6px;
  padding: 10px 12px;
  overflow-x: auto;
  font-size: 0.8rem;
  margin: 0;
  max-height: 220px;
}

.replay-controls {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 16px;
  flex-wrap: wrap;
}
.replay-progress {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.final-answer {
  margin-top: 18px;
  padding-top: 18px;
  border-top: 1px dashed var(--border);
}
.final-answer h4 { margin: 0 0 8px; font-size: 0.95rem; }
.final-answer pre {
  background: var(--code-bg);
  border-radius: 6px;
  padding: 12px;
  overflow-x: auto;
  font-size: 0.82rem;
  margin: 0;
}

/* --- Stat tiles --- */
.stat-tiles {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 14px;
  margin-bottom: 20px;
}
.stat-tile {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  box-shadow: var(--shadow);
}
.stat-tile .stat-value {
  font-size: 1.6rem;
  font-weight: 700;
}
.stat-tile .stat-label {
  color: var(--text-muted);
  font-size: 0.8rem;
  margin-top: 4px;
}

.callout {
  border-radius: 8px;
  padding: 14px 16px;
  font-size: 0.88rem;
  margin-bottom: 24px;
}
.callout-warning {
  background: var(--status-partial-bg);
  color: var(--status-partial-text);
  border: 1px solid var(--status-partial-text);
}

.table-wrap { overflow-x: auto; }
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  min-width: 560px;
}
.data-table th, .data-table td {
  text-align: left;
  padding: 8px 10px;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}
.data-table th {
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}
.data-table tr:last-child td { border-bottom: none; }

/* --- Phase strip --- */
.phase-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 12px;
  margin-bottom: 28px;
}
.phase-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px;
  box-shadow: var(--shadow);
}
.phase-card .phase-num {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 600;
}
.phase-card .phase-name {
  font-weight: 600;
  margin: 4px 0 8px;
  font-size: 0.92rem;
}
.phase-card .phase-note {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 8px;
}

.status-done { background: var(--status-done-bg); color: var(--status-done-text); }
.status-mostly-verified { background: var(--status-verified-bg); color: var(--status-verified-text); }
.status-code-ready-not-run,
.status-logic-tested-not-e2e { background: var(--status-partial-bg); color: var(--status-partial-text); }
.status-not-started { background: var(--status-notstarted-bg); color: var(--status-notstarted-text); }

.site-footer {
  padding: 32px 0 60px;
  color: var(--text-muted);
  font-size: 0.85rem;
}
.footer-inner a { color: var(--text-muted); }
.footer-note { margin-top: 8px; }