/* ============================================================
   USDX — Whitepaper Stylesheet
   ============================================================ */

:root {
  --bg-100: #020810;
  --bg-200: #060D1A;
  --bg-card: #0D1D30;
  --border-subtle: rgba(255, 255, 255, 0.05);
  --border-default: rgba(255, 255, 255, 0.09);
  --border-accent: rgba(37, 99, 235, 0.35);

  --blue-400: #60A5FA;
  --blue-500: #3B82F6;
  --blue-600: #2563EB;
  --cyan-400: #22D3EE;
  --green-400: #4ADE80;
  --amber-400: #FBBF24;
  --red-400: #F87171;

  --text-primary: #F0F6FF;
  --text-secondary: #94A3B8;
  --text-muted: #4B6280;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  --sidebar-width: 280px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --transition: 0.2s ease;
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
  background: var(--bg-100);
  color: var(--text-primary);
  font-family: var(--font-sans);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }

/* ── Top bar ─────────────────────────────────────────────────── */
.wp-topbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: 64px;
  background: rgba(2, 8, 16, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  padding: 0 32px;
  gap: 24px;
}

.wp-topbar-logo {
  display: flex;
  align-items: center;
  margin-right: auto;
}

.nav-logo-img {
  height: 36px;
  width: auto;
}

.wp-topbar-badge {
  font-size: 11px;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 999px;
  background: rgba(37, 99, 235, 0.15);
  border: 1px solid rgba(37, 99, 235, 0.3);
  color: var(--blue-400);
  letter-spacing: 0.05em;
}

.wp-topbar-back {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-default);
  transition: color var(--transition), background-color var(--transition);
}

.wp-topbar-back:hover {
  color: var(--text-primary);
  background: rgba(255,255,255,0.05);
}

.wp-download-btn {
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 14px;
  font-weight: 600;
  padding: 8px 18px;
  background: var(--blue-600);
  color: #fff;
  border-radius: var(--radius-sm);
  cursor: pointer;
  border: none;
  transition: background-color var(--transition);
}

.wp-download-btn:focus-visible {
  outline: 2px solid var(--blue-400);
  outline-offset: 3px;
}

.wp-download-btn:hover {
  background: var(--blue-500);
}

/* ── Layout ──────────────────────────────────────────────────── */
.wp-layout {
  display: flex;
  padding-top: 64px;
  min-height: 100vh;
}

/* ── Sidebar ─────────────────────────────────────────────────── */
.wp-sidebar {
  width: var(--sidebar-width);
  flex-shrink: 0;
  position: fixed;
  top: 64px; bottom: 0; left: 0;
  overflow-y: auto;
  border-right: 1px solid var(--border-subtle);
  background: var(--bg-200);
  padding: 28px 0;
  scrollbar-width: thin;
  scrollbar-color: var(--border-default) transparent;
}

.wp-sidebar::-webkit-scrollbar { width: 4px; }
.wp-sidebar::-webkit-scrollbar-track { background: transparent; }
.wp-sidebar::-webkit-scrollbar-thumb { background: var(--border-default); border-radius: 2px; }

.sidebar-header {
  padding: 0 20px 20px;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 16px;
}

.sidebar-header h2 {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.toc-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 7px 20px;
  font-size: 13px;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
  border-left: 2px solid transparent;
  line-height: 1.4;
}

.toc-item:hover {
  color: var(--text-primary);
  background: rgba(255,255,255,0.03);
}

.toc-item.active {
  color: var(--blue-400);
  border-left-color: var(--blue-500);
  background: rgba(37, 99, 235, 0.08);
  font-weight: 600;
}

.toc-num {
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-muted);
  flex-shrink: 0;
  width: 22px;
}

.toc-item.active .toc-num {
  color: var(--blue-400);
}

/* ── Main content ────────────────────────────────────────────── */
.wp-content {
  flex: 1;
  margin-left: var(--sidebar-width);
  max-width: 820px;
  padding: 60px 64px 120px;
}

/* ── Cover ───────────────────────────────────────────────────── */
.wp-cover {
  margin-bottom: 72px;
  padding-bottom: 56px;
  border-bottom: 1px solid var(--border-subtle);
}

.wp-cover-eyebrow {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--blue-400);
  margin-bottom: 16px;
}

.wp-cover h1 {
  font-size: clamp(32px, 4vw, 52px);
  font-weight: 900;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 20px;
}

.wp-cover-gradient {
  background: linear-gradient(135deg, #60A5FA, #22D3EE);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.wp-cover-desc {
  font-size: 17px;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 580px;
  margin-bottom: 32px;
}

.wp-meta-row {
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.wp-meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--text-muted);
}

.wp-meta-item strong {
  color: var(--text-secondary);
  font-weight: 600;
}

/* ── Sections ────────────────────────────────────────────────── */
.wp-section {
  margin-bottom: 72px;
  scroll-margin-top: 88px;
}

.wp-section h2 {
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.025em;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-subtle);
}

.section-num {
  font-size: 13px;
  font-family: var(--font-mono);
  color: var(--blue-400);
  background: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(37, 99, 235, 0.25);
  padding: 3px 9px;
  border-radius: 6px;
}

.wp-section h3 {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-top: 32px;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.wp-section h4 {
  font-size: 12px;
  font-weight: 700;
  margin-top: 24px;
  margin-bottom: 10px;
  color: var(--blue-400);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.wp-section p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}

.wp-section ul, .wp-section ol {
  padding-left: 0;
  margin-bottom: 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.wp-section ul li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.wp-section ul li::before {
  content: '→';
  color: var(--blue-400);
  flex-shrink: 0;
  font-size: 13px;
  margin-top: 3px;
}

.wp-section ol {
  counter-reset: list-counter;
}

.wp-section ol li {
  display: flex;
  gap: 12px;
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
  counter-increment: list-counter;
}

.wp-section ol li::before {
  content: counter(list-counter);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--blue-400);
  background: rgba(37, 99, 235, 0.15);
  border: 1px solid rgba(37, 99, 235, 0.25);
  width: 22px; height: 22px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 2px;
}

/* ── Invariant box ───────────────────────────────────────────── */
.invariant-box {
  background: rgba(6, 182, 212, 0.06);
  border: 1px solid rgba(6, 182, 212, 0.2);
  border-left: 3px solid var(--cyan-400);
  border-radius: var(--radius-sm);
  padding: 20px 24px;
  margin: 20px 0;
}

.invariant-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan-400);
  margin-bottom: 10px;
}

.invariant-formula {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--text-primary);
  background: rgba(0, 0, 0, 0.3);
  padding: 12px 16px;
  border-radius: 6px;
  margin-bottom: 8px;
}

.invariant-desc {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ── Code block ──────────────────────────────────────────────── */
pre.code-block {
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  padding: 20px 24px;
  overflow-x: auto;
  margin: 20px 0;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--cyan-400);
}

code {
  font-family: var(--font-mono);
  font-size: 13px;
  background: rgba(255,255,255,0.07);
  padding: 2px 6px;
  border-radius: 4px;
  color: var(--cyan-400);
}

/* ── Info / warning callout ──────────────────────────────────── */
.callout {
  display: flex;
  gap: 14px;
  padding: 18px 20px;
  border-radius: var(--radius-sm);
  margin: 20px 0;
}

.callout-info {
  background: rgba(37, 99, 235, 0.08);
  border: 1px solid rgba(37, 99, 235, 0.2);
}

.callout-warning {
  background: rgba(251, 191, 36, 0.07);
  border: 1px solid rgba(251, 191, 36, 0.2);
}

.callout-success {
  background: rgba(34, 197, 94, 0.07);
  border: 1px solid rgba(34, 197, 94, 0.2);
}

.callout-icon {
  font-size: 18px;
  flex-shrink: 0;
  margin-top: 1px;
}

.callout p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 0;
}

.callout-info p { color: var(--blue-400); }
.callout-warning p { color: var(--amber-400); }
.callout-success p { color: var(--green-400); }

/* ── Data table ──────────────────────────────────────────────── */
.data-table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 14px;
}

.data-table th {
  text-align: left;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-default);
}

.data-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  vertical-align: top;
}

.data-table td:first-child {
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
}

.data-table tr:last-child td { border-bottom: none; }

.data-table tr:hover td {
  background: rgba(255,255,255,0.02);
}

/* ── Reserve composition ─────────────────────────────────────── */
.reserve-table-wrap {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin: 24px 0;
}

.reserve-row {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 24px;
  border-bottom: 1px solid var(--border-subtle);
}

.reserve-row:last-child { border-bottom: none; }

.reserve-color {
  width: 12px; height: 12px;
  border-radius: 3px;
  flex-shrink: 0;
}

.reserve-name {
  flex: 1;
  font-size: 14px;
  font-weight: 600;
}

.reserve-range {
  font-size: 13px;
  color: var(--text-secondary);
}

.reserve-pct {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  width: 60px;
  text-align: right;
}

/* ── Risk matrix ─────────────────────────────────────────────── */
.risk-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin: 24px 0;
}

.risk-card {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  padding: 20px;
}

.risk-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.risk-card h4 {
  font-size: 14px;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0;
  text-transform: none;
  letter-spacing: 0;
}

.risk-level {
  font-size: 11px;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 999px;
}

.risk-medium {
  background: rgba(251, 191, 36, 0.12);
  color: var(--amber-400);
  border: 1px solid rgba(251, 191, 36, 0.25);
}

.risk-low {
  background: rgba(34, 197, 94, 0.12);
  color: var(--green-400);
  border: 1px solid rgba(34, 197, 94, 0.25);
}

.risk-card p {
  font-size: 13px;
  margin: 0;
  line-height: 1.65;
}

/* ── Governance roles ────────────────────────────────────────── */
.role-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin: 20px 0;
}

.role-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
}

.role-icon {
  width: 36px; height: 36px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  flex-shrink: 0;
  background: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(37, 99, 235, 0.2);
}

.role-item h4 {
  font-size: 14px;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0 0 4px;
  text-transform: none;
  letter-spacing: 0;
}

.role-item p {
  font-size: 13px;
  margin: 0;
  line-height: 1.6;
}

/* ── Chain comparison table ──────────────────────────────────── */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 13px;
}

.comparison-table th {
  padding: 12px 16px;
  text-align: center;
  font-size: 13px;
  font-weight: 700;
  border-bottom: 1px solid var(--border-default);
}

.comparison-table th:first-child { text-align: left; }

.comparison-table td {
  padding: 13px 16px;
  text-align: center;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

.comparison-table td:first-child {
  text-align: left;
  font-weight: 600;
  color: var(--text-primary);
}

.comparison-table tr:last-child td { border-bottom: none; }

.check { color: var(--green-400); font-size: 16px; }
.cross { color: var(--red-400); font-size: 16px; }
.partial { color: var(--amber-400); font-size: 16px; }

.highlight-col { background: rgba(37, 99, 235, 0.06); }

/* ── Responsive ──────────────────────────────────────────────── */
@media (max-width: 1024px) {
  .wp-sidebar { display: none; }
  .wp-content { margin-left: 0; }
  .wp-topbar { padding: 0 20px; }
}

@media (max-width: 768px) {
  .wp-content { padding: 40px 24px 80px; }
  .risk-grid { grid-template-columns: 1fr; }
  .wp-topbar-back span { display: none; }
}