:root {
  --ink: #1a2433;
  --muted: #5b6b7d;
  --border: #dde3ea;
  --accent: #2a6fdb;
  --bg-card: #ffffff;
  --bg-page: #f4f6f9;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink);
  background: var(--bg-page);
  line-height: 1.5;
}

header {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2rem 1.5rem 0.5rem;
}

h1 { margin: 0 0 0.4rem; font-size: 1.6rem; }

.subtitle, .updated-at { color: var(--muted); font-size: 0.92rem; max-width: 70ch; }
.updated-at { font-size: 0.82rem; margin-top: 0.5rem; }

main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 1rem 1.5rem 3rem;
  display: grid;
  gap: 1.5rem;
}

.variant-tabs, .subtabs {
  display: flex;
  gap: 0.25rem;
  border-bottom: 1px solid var(--border);
}

.variant-tabs { margin-bottom: 1.25rem; }
.subtabs { margin: 0 0 1.25rem; }

.variant-tab, .subtab {
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  font: inherit;
  color: var(--muted);
  padding: 0.6rem 1rem;
}

.subtab { font-size: 0.85rem; padding: 0.4rem 0.8rem; }

.variant-tab.active, .subtab.active { color: var(--accent); border-bottom-color: var(--accent); }
.variant-tab:hover, .subtab:hover { color: var(--ink); }

.variant-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.25rem 1.5rem;
}

.variant-description { color: var(--muted); margin: 0 0 1rem; font-size: 0.9rem; }

.side-buy { color: #1a8a4a; font-weight: 600; }
.side-sell { color: #c0392b; font-weight: 600; }

.curve-modes {
  display: flex;
  gap: 0.4rem;
  margin: 0 0 1rem;
}

.curve-mode {
  background: var(--bg-page);
  border: 1px solid var(--border);
  border-radius: 999px;
  cursor: pointer;
  font: inherit;
  font-size: 0.8rem;
  color: var(--muted);
  padding: 0.35rem 0.9rem;
}

.curve-mode.active { background: var(--accent); border-color: var(--accent); color: #fff; }
.curve-mode:hover:not(.active) { color: var(--ink); border-color: var(--accent); }

.metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(110px, 1fr));
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.metric {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.6rem 0.8rem;
}

.metric-label { font-size: 0.75rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.03em; }
.metric-value { font-size: 1.15rem; font-weight: 600; margin-top: 0.15rem; }

.benchmark-compare { max-width: 360px; margin: 0 auto 1.25rem; text-align: center; }
.benchmark-compare table { text-align: left; }
.benchmark-compare h4 { font-size: 0.8rem; color: var(--muted); margin: 0 0 0.4rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.03em; }
.compare-table { font-size: 0.85rem; }
.compare-table th, .compare-table td { padding: 0.3rem 0.5rem; }
.compare-table th:not(:first-child), .compare-table td:not(:first-child) { text-align: right; }

.equity-chart { max-height: 260px; margin-bottom: 1.25rem; }

h3 { font-size: 1rem; margin: 0 0 0.6rem; }

table { width: 100%; border-collapse: collapse; font-size: 0.88rem; }
table a { color: var(--accent); text-decoration: none; }
table a:hover { text-decoration: underline; }
th, td { text-align: left; padding: 0.4rem 0.6rem; border-bottom: 1px solid var(--border); }
th { color: var(--muted); font-weight: 600; font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.03em; }

.empty { color: var(--muted); font-size: 0.9rem; font-style: italic; }

.insights-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-top: 1.5rem;
}

.insight-card {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.9rem 1rem;
}

.insight-wide { grid-column: 1 / -1; }

.insight-note { color: var(--muted); font-size: 0.82rem; margin: 0 0 0.6rem; }

.contributors-col + .contributors-col { margin-top: 1rem; }
.contributors-col h4 { font-size: 0.85rem; margin: 0 0 0.4rem; color: var(--muted); }

.contributor-list, .concentration-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.4rem;
}

.contributor-list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.6rem;
  font-size: 0.85rem;
}

.contributor-dates { color: var(--muted); font-size: 0.76rem; white-space: nowrap; }

.concentration-list li {
  display: grid;
  grid-template-columns: 5rem 1fr 3.2rem;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.85rem;
}

.concentration-bar {
  display: block;
  height: 8px;
  border-radius: 999px;
  background: var(--bg-page);
  overflow: hidden;
}

.concentration-bar span {
  display: block;
  height: 100%;
  background: var(--accent);
  border-radius: 999px;
}

.concentration-pct { text-align: right; color: var(--muted); }

@media (max-width: 720px) {
  .insights-grid { grid-template-columns: 1fr; }
}

footer {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem 2rem;
  color: var(--muted);
  font-size: 0.78rem;
}