/* ==========================================================================
   Critical Issues — design tokens (light/dark, validated palette)
   ========================================================================== */

:root {
  color-scheme: light;

  /* chrome & ink */
  --surface-1:      #fcfcfb;
  --page-plane:      #f9f9f7;
  --text-primary:    #0b0b0b;
  --text-secondary:  #52514e;
  --text-muted:      #898781;
  --gridline:        #e1e0d9;
  --baseline:        #c3c2b7;
  --border:          rgba(11,11,11,0.10);
  --success-text:    #006300;

  /* categorical slots (fixed order — never cycled) */
  --series-1: #2a78d6; /* blue */
  --series-2: #eb6834; /* orange */
  --series-3: #1baf7a; /* aqua */
  --series-4: #eda100; /* yellow */
  --series-5: #e87ba4; /* magenta */
  --series-6: #008300; /* green */
  --series-7: #4a3aa7; /* violet */
  --series-8: #e34948; /* red */

  /* sequential (blue ramp) */
  --seq-100: #cde2fb;
  --seq-400: #3987e5;
  --seq-700: #0d366b;

  /* status (fixed, never themed) */
  --status-good: #0ca30c;
  --status-warning: #fab219;
  --status-serious: #ec835a;
  --status-critical: #d03b3b;

  --radius: 10px;
  --shadow: 0 1px 2px rgba(11,11,11,0.06), 0 1px 12px rgba(11,11,11,0.04);
  --font: system-ui, -apple-system, "Segoe UI", sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --surface-1:      #1a1a19;
    --page-plane:      #0d0d0d;
    --text-primary:    #ffffff;
    --text-secondary:  #c3c2b7;
    --text-muted:      #898781;
    --gridline:        #2c2c2a;
    --baseline:        #383835;
    --border:          rgba(255,255,255,0.10);
    --success-text:    #0ca30c;

    --series-1: #3987e5;
    --series-2: #d95926;
    --series-3: #199e70;
    --series-4: #c98500;
    --series-5: #d55181;
    --series-6: #008300;
    --series-7: #9085e9;
    --series-8: #e66767;
  }
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --surface-1:      #1a1a19;
  --page-plane:      #0d0d0d;
  --text-primary:    #ffffff;
  --text-secondary:  #c3c2b7;
  --text-muted:      #898781;
  --gridline:        #2c2c2a;
  --baseline:        #383835;
  --border:          rgba(255,255,255,0.10);
  --success-text:    #0ca30c;

  --series-1: #3987e5;
  --series-2: #d95926;
  --series-3: #199e70;
  --series-4: #c98500;
  --series-5: #d55181;
  --series-6: #008300;
  --series-7: #9085e9;
  --series-8: #e66767;
}

* { box-sizing: border-box; }

[hidden] { display: none !important; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--page-plane);
  color: var(--text-primary);
  font-family: var(--font);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; }

a { color: var(--series-1); }

.wrap {
  max-width: 1100px;
  margin: 0 auto;
  padding-inline: 20px;
}

/* ---------- header / nav ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--surface-1) 92%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 60px;
  flex-wrap: wrap;
  padding-block: 8px 2px;
  row-gap: 2px;
}

.brand {
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  text-decoration: none;
  white-space: nowrap;
}

.brand span { color: var(--series-1); }

.main-nav {
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
  order: 3;
  width: 100%;
  margin-inline: -10px;
}

.view-toggle { margin-left: auto; }

.main-nav a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 10px;
  border-radius: 8px;
}

.main-nav a:hover { background: var(--gridline); color: var(--text-primary); }

.theme-toggle {
  border: 1px solid var(--border);
  background: var(--surface-1);
  color: var(--text-secondary);
  border-radius: 8px;
  padding: 7px 10px;
  font-size: 0.85rem;
  cursor: pointer;
  font-family: var(--font);
}
.theme-toggle:hover { color: var(--text-primary); }

.view-toggle {
  display: inline-flex;
  background: var(--gridline);
  border-radius: 999px;
  padding: 3px;
  gap: 2px;
  flex: none;
}

.view-btn {
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 650;
  padding: 7px 14px;
  border-radius: 999px;
  cursor: pointer;
  font-family: var(--font);
  white-space: nowrap;
}
.view-btn:hover { color: var(--text-primary); }
.view-btn.active {
  background: var(--surface-1);
  color: var(--text-primary);
  box-shadow: var(--shadow);
}

/* ---------- hero ---------- */

.hero {
  padding-block: 56px 40px;
  border-bottom: 1px solid var(--border);
}

.hero h1 {
  font-size: clamp(1.9rem, 4vw, 2.75rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  margin: 0 0 14px;
  max-width: 18ch;
}

.hero p.lead {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 62ch;
  margin: 0 0 28px;
}

.hero-links {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid var(--border);
  background: var(--surface-1);
  color: var(--text-primary);
  text-decoration: none;
  padding: 8px 14px;
  border-radius: 999px;
  font-size: 0.88rem;
  font-weight: 500;
}
.pill:hover { border-color: var(--baseline); }
.pill .dot { width: 8px; height: 8px; border-radius: 50%; flex: none; }

/* ---------- section ---------- */

.section {
  padding-block: 52px;
  border-bottom: 1px solid var(--border);
  scroll-margin-top: 110px;
}

.section:last-of-type { border-bottom: none; }

.section-head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 22px;
}

.section-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex: none;
  font-size: 1.2rem;
}

.section-head h2 {
  font-size: 1.5rem;
  margin: 0 0 4px;
  letter-spacing: -0.01em;
}

.section-head p {
  margin: 0;
  color: var(--text-secondary);
  max-width: 70ch;
}

/* ---------- chart cards ---------- */

.chart-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(420px, 1fr));
  gap: 18px;
}

.chart-card {
  background: var(--surface-1);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 20px 16px;
  box-shadow: var(--shadow);
}

.chart-card .chart-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 4px;
}

.chart-title-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.chart-card h3 {
  margin: 0;
  font-size: 1.02rem;
  letter-spacing: -0.005em;
}

.trend-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.68rem;
  font-weight: 650;
  letter-spacing: 0.01em;
  text-transform: uppercase;
  padding: 3px 8px;
  border-radius: 999px;
  flex: none;
}
.trend-badge::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  flex: none;
}
.trend-badge.trend-good {
  color: var(--status-good);
  background: color-mix(in srgb, var(--status-good) 14%, transparent);
}
.trend-badge.trend-good::before { background: var(--status-good); }
.trend-badge.trend-bad {
  color: var(--status-critical);
  background: color-mix(in srgb, var(--status-critical) 14%, transparent);
}
.trend-badge.trend-bad::before { background: var(--status-critical); }
.trend-badge.trend-mixed {
  color: var(--status-warning);
  background: color-mix(in srgb, var(--status-warning) 18%, transparent);
}
.trend-badge.trend-mixed::before { background: var(--status-warning); }

.chart-card .takeaway {
  color: var(--text-secondary);
  font-size: 0.88rem;
  margin: 4px 0 12px;
}

.table-toggle {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  border-radius: 7px;
  padding: 5px 9px;
  font-size: 0.75rem;
  cursor: pointer;
  font-family: var(--font);
  flex: none;
}
.table-toggle:hover { color: var(--text-primary); border-color: var(--baseline); }

.chart-viz { position: relative; }

.chart-viz svg { display: block; width: 100%; height: auto; overflow: visible; }

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 10px;
  font-size: 0.78rem;
  color: var(--text-secondary);
}
.legend .item { display: flex; align-items: center; gap: 6px; }
.legend .swatch { width: 14px; height: 3px; border-radius: 2px; flex: none; }
.legend .swatch.bar { width: 10px; height: 10px; border-radius: 3px; }

.chart-source {
  margin-top: 12px;
  font-size: 0.75rem;
  color: var(--text-muted);
}
.chart-source a { color: var(--text-muted); }

/* data table (accessible fallback) */
.data-table-wrap { overflow-x: auto; margin-top: 10px; }
table.data-table {
  border-collapse: collapse;
  width: 100%;
  font-size: 0.82rem;
}
table.data-table th, table.data-table td {
  text-align: right;
  padding: 6px 10px;
  border-bottom: 1px solid var(--gridline);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
table.data-table th:first-child, table.data-table td:first-child {
  text-align: left;
  font-variant-numeric: normal;
}
table.data-table th { color: var(--text-secondary); font-weight: 600; }

/* ---------- tooltip ---------- */

.viz-tooltip {
  position: absolute;
  pointer-events: none;
  background: var(--surface-1);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  border-radius: 8px;
  padding: 8px 10px;
  font-size: 0.78rem;
  min-width: 120px;
  opacity: 0;
  transform: translate(-50%, -100%);
  transition: opacity 0.08s ease;
  z-index: 20;
}
.viz-tooltip.visible { opacity: 1; }
.viz-tooltip .t-head {
  color: var(--text-muted);
  margin-bottom: 4px;
  font-size: 0.72rem;
}
.viz-tooltip .t-row {
  display: flex;
  align-items: center;
  gap: 6px;
  justify-content: space-between;
}
.viz-tooltip .t-key { display: flex; align-items: center; gap: 5px; color: var(--text-secondary); }
.viz-tooltip .t-key .line { width: 10px; height: 2px; border-radius: 1px; flex: none; }
.viz-tooltip .t-val { font-weight: 650; color: var(--text-primary); font-variant-numeric: tabular-nums; }

/* ---------- footer ---------- */

.site-footer {
  padding-block: 32px;
  color: var(--text-muted);
  font-size: 0.85rem;
}
.site-footer a { color: var(--text-muted); }

/* ---------- responsive ---------- */

@media (max-width: 640px) {
  .hero { padding-block: 40px 28px; }
  .section { padding-block: 40px; }
  .chart-grid { grid-template-columns: 1fr; }
}

.panel-title {
  margin: 14px 0 6px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
}
.panel-title:first-child { margin-top: 4px; }

.section .chart-card {
  background: color-mix(in srgb, var(--section-accent, transparent) 5%, var(--surface-1));
  border-color: color-mix(in srgb, var(--section-accent, transparent) 22%, var(--border));
}

.pair-link {
  display: inline-block;
  margin-top: 8px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-primary);
  text-decoration: none;
  border-bottom: 2px solid var(--section-accent, var(--baseline));
  padding-bottom: 1px;
}
.pair-link:hover { color: var(--text-secondary); }

.explainer-card { grid-column: 1 / -1; }
.explainer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 14px;
  margin-top: 6px;
}
.explainer-item {
  border-top: 3px solid var(--section-accent, var(--baseline));
  padding-top: 10px;
}
.explainer-item h4 { margin: 0 0 4px; font-size: 0.92rem; }
.explainer-item p { margin: 0 0 6px; font-size: 0.82rem; color: var(--text-secondary); }
.explainer-item ul { margin: 0; padding-left: 16px; font-size: 0.8rem; color: var(--text-secondary); }
.explainer-item li { margin-bottom: 2px; }