/* ── Design tokens ───────────────────────────────────────────── */
:root {
  --bg:           #0d0e0f;
  --surface:      #161819;
  --surface-2:    #1e2022;
  --border:       rgba(255, 255, 255, 0.07);
  --border-hi:    rgba(255, 255, 255, 0.13);
  --accent:       #DA291C;
  --accent-glow:  rgba(218, 41, 28, 0.3);
  --text:         #efefef;
  --text-dim:     rgba(239, 239, 239, 0.55);
  --text-muted:   rgba(239, 239, 239, 0.27);
  --radius:       18px;
  --radius-sm:    9px;
  --font-mono:    'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  --shadow:       0 6px 48px rgba(0, 0, 0, 0.4);
}

/* ── Reset ───────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  scrollbar-width: none;
}
html::-webkit-scrollbar { display: none; }

/* ── Base ────────────────────────────────────────────────────── */
body {
  background-color: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, 'Segoe UI', Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  scrollbar-width: none;
}
body::-webkit-scrollbar { display: none; }

/* ── Page wrapper ────────────────────────────────────────────── */
.page {
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* ── Colorblind toggle ───────────────────────────────────────── */
#colorblind-toggle {
  position: fixed;
  top: 16px;
  right: 20px;
  z-index: 200;
}

/* ── Buttons ─────────────────────────────────────────────────── */
button {
  background-color: var(--surface-2);
  color: var(--text-dim);
  border: 1px solid var(--border-hi);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  padding: 5px 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background-color 0.18s, color 0.18s, border-color 0.18s;
  white-space: nowrap;
}
button:hover {
  background-color: #252829;
  color: var(--text);
  border-color: rgba(255, 255, 255, 0.22);
}

/* ── Selects ─────────────────────────────────────────────────── */
select {
  background-color: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--border-hi);
  font-family: system-ui, sans-serif;
  font-size: 13px;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background-color 0.18s;
  appearance: none;
  -webkit-appearance: none;
}
select:hover { background-color: #252829; }

/* ── Spacer ──────────────────────────────────────────────────── */
.spacer { height: 14vh; }

/* ── Section base ────────────────────────────────────────────── */
.section {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
}

/* ── Section title ───────────────────────────────────────────── */
.section-title {
  font-size: clamp(20px, 2vw, 34px);
  font-weight: 700;
  letter-spacing: -0.025em;
  text-align: center;
  margin-bottom: 1.4vw;
  color: var(--text);
}

/* ── Chart cards ─────────────────────────────────────────────── */
.chart-card {
  width: 82vw;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.8vw 2.2vw 1.4vw;
  box-shadow: var(--shadow);
  transition: transform 0.18s ease;
}
.chart-card:hover { transform: scale(1.015); }

/* ── Dual chart layout ───────────────────────────────────────── */
.dual-chart-row {
  display: flex;
  gap: 1.4vw;
  width: 82vw;
}

.chart-card-half {
  flex: 1;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.8vw 2.2vw 1.4vw;
  box-shadow: var(--shadow);
  transition: transform 0.18s ease;
}
.chart-card-half:hover { transform: scale(1.015); }


.chart-btn-row {
  display: flex;
  gap: 8px;
  margin-top: 0.6vw;
}
.chart-btn-row button {
  font-size: 10px;
  padding: 4px 8px;
}

/* ── Chart footer (note left, source right) ──────────────────── */
.chart-footer {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-top: 1vw;
  gap: 4vw;
}

.chart-note {
  font-size: 12px;
  font-family: var(--font-mono);
  color: var(--text-muted);
  letter-spacing: 0.03em;
  flex: 1;
}

.chart-source {
  font-size: 12px;
  font-family: var(--font-mono);
  color: var(--text-muted);
  text-align: right;
  letter-spacing: 0.03em;
  white-space: nowrap;
  text-decoration: none;
  transition: color 0.18s;
}
.chart-source:hover {
  color: var(--text-dim);
}

/* ── Prose ───────────────────────────────────────────────────── */
.prose {
  width: 72vw;
  font-size: clamp(15px, 1.05vw, 18px);
  color: var(--text-dim);
  line-height: 1.85;
  margin-top: 1.8vw;
  text-align: center;
}

.dual-prose-row {
  display: flex;
  gap: 2vw;
  width: 82vw;
  margin-top: 1.6vw;
}
.prose-half {
  flex: 1;
  font-size: clamp(15px, 1.05vw, 18px);
  color: var(--text-dim);
  line-height: 1.85;
}

/* ── Hero ────────────────────────────────────────────────────── */
#section-intro {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 8vh 0 6vh;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 5vw;
  width: 82vw;
  margin-bottom: 3.5vw;
}

.hero-image-wrap {
  border-radius: var(--radius);
  transition: transform 0.18s ease;
}
.hero-image-wrap:hover { transform: scale(1.015); }

.hero-image {
  width: 100%;
  display: block;
  border-radius: var(--radius);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.65), 0 0 0 1px var(--border);
}

.hero-text {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.hero-tag {
  font-size: 13px;
  font-family: var(--font-mono);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
}

.hero-title {
  font-size: clamp(28px, 3.8vw, 66px);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.07;
  color: var(--text);
}

.hero-subtitle {
  font-size: clamp(14px, 1.1vw, 20px);
  color: var(--text-dim);
  font-weight: 400;
  line-height: 1.5;
}

.hero-prose {
  width: 82vw;
  font-size: clamp(15px, 1.05vw, 18px);
  color: var(--text-dim);
  line-height: 1.9;
  border-top: 1px solid var(--border);
  padding-top: 2.2vw;
}

/* ── Conclusion ──────────────────────────────────────────────── */
.conclusion {
  min-height: 60vh;
  justify-content: center;
  padding: 8vh 0;
}

.conclusion-title {
  font-size: clamp(36px, 5vw, 80px);
  font-weight: 800;
  letter-spacing: -0.04em;
  margin-bottom: 2vw;
  color: var(--text);
}

/* ── Red Line nav ────────────────────────────────────────────── */
#rl-nav {
  position: fixed;
  left: 0;
  top: 0;
  width: 44px;
  height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 100;
}

#rl-track {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 3px;
  background-color: rgba(218, 41, 28, 0.18);
  z-index: -1;
}

#rl-progress {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 3px;
  height: 0;
  background-color: var(--accent);
  transition: height 0.4s ease;
  z-index: -1;
}

.rl-station {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  flex: 1;
  width: 100%;
  cursor: pointer;
  max-height: 25vh;
}

.rl-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  border: 2px solid var(--accent);
  background-color: var(--bg);
  flex-shrink: 0;
  z-index: 1;
  transition: background-color 0.25s, transform 0.25s, box-shadow 0.25s;
}
.rl-station.terminal .rl-dot {
  width: 13px;
  height: 13px;
  border-width: 2.5px;
}

.rl-station:hover .rl-dot {
  transform: scale(1.5);
  box-shadow: 0 0 8px var(--accent-glow);
}
.rl-station.active .rl-dot {
  background-color: var(--accent);
  transform: scale(1.5);
  box-shadow: 0 0 14px var(--accent-glow);
}

.rl-label {
  position: absolute;
  left: calc(100% + 6px);
  font-size: 10px;
  font-family: var(--font-mono);
  letter-spacing: 0.07em;
  text-transform: uppercase;
  white-space: nowrap;
  opacity: 0;
  transition: opacity 0.2s;
  pointer-events: none;
  color: var(--text-dim);
}
.rl-station:hover .rl-label,
.rl-station.active .rl-label { opacity: 1; }

/* ── Footnote ────────────────────────────────────────────────── */
.footnote {
  width: 100%;
  text-align: center;
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-muted);
  padding: 2vh 0 3vh;
  letter-spacing: 0.06em;
}

/* ── Inline note read-more button ────────────────────────────── */
.chart-note-btn {
  display: inline;
  background: none;
  border: none;
  padding: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.03em;
  color: var(--text-dim);
  cursor: pointer;
  text-decoration: none;
  border-radius: 0;
  white-space: nowrap;
}
.chart-note-btn:hover {
  background: none;
  color: var(--text);
  border-color: transparent;
}

/* ── Canvas ──────────────────────────────────────────────────── */
canvas {
  display: block;
  width: 100% !important;
}