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

/* ── Design Tokens ── */
:root {
  color-scheme: dark;
  --bg: #0a0e17;
  --bg-glow: #141a29;
  --bg-deep: #050813;
  --bg-soft: #111827;
  --surface: rgba(22, 27, 38, 0.74);
  --surface-strong: rgba(22, 27, 38, 0.9);
  --border: rgba(148, 163, 184, 0.15);
  --border-strong: rgba(148, 163, 184, 0.25);
  --text: #f3f4f6;
  --muted: #9ca3af;
  --muted-strong: #d1d5db;
  --accent: #06b6d4;
  --accent-strong: #0891b2;
  --accent-alpha: rgba(6, 182, 212, 0.12);
  --on-accent: #0a0e17;
  --radius-lg: 1rem;
  --radius-md: 0.5rem;
}

:root.light {
  color-scheme: light;
  --bg: #f8fafc;
  --bg-glow: #fff;
  --bg-deep: #e2e8f0;
  --bg-soft: #f1f5f9;
  --surface: rgba(255, 255, 255, 0.78);
  --surface-strong: rgba(255, 255, 255, 0.94);
  --border: rgba(15, 23, 42, 0.08);
  --border-strong: rgba(15, 23, 42, 0.14);
  --text: #0f172a;
  --muted: #64748b;
  --muted-strong: #334155;
  --accent: #0891b2;
  --accent-strong: #0e7490;
  --accent-alpha: rgba(8, 145, 178, 0.08);
  --on-accent: #ffffff;
}

/* ── Base ── */
html {
  background-color: var(--bg);
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  background: radial-gradient(circle at top left, var(--accent-alpha), transparent 30rem),
              linear-gradient(135deg, var(--bg) 0%, var(--bg-soft) 48%, var(--bg) 100%);
  color: var(--text);
  font-family: 'Inter', ui-sans-serif, system-ui, sans-serif;
  -webkit-tap-highlight-color: transparent;
  line-height: 1.7;
}

@supports (color: color-mix(in lab, red, red)) {
  body {
    background: radial-gradient(circle at top left, color-mix(in srgb, var(--accent) 12%, transparent), transparent 30rem),
                linear-gradient(135deg, var(--bg) 0%, var(--bg-soft) 48%, var(--bg) 100%);
  }
}

/* ── Shell ── */
.shell {
  width: min(100% - 32px, 720px);
  margin: 0 auto;
  padding: 3rem 0 4rem;
}

/* ── Header ── */
.header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.logo {
  font-family: 'Space Grotesk', ui-sans-serif, system-ui, sans-serif;
  font-weight: 900;
  font-size: clamp(1.5rem, 4vw, 2.25rem);
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.badge {
  display: inline-block;
  font-family: 'Space Grotesk', ui-sans-serif, system-ui, sans-serif;
  font-weight: 600;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-alpha);
  border: 1px solid var(--accent);
  border-radius: 2rem;
  padding: 0.25rem 0.85rem;
}

.effective-date {
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 1.5rem;
}

.intro {
  color: var(--muted-strong);
  margin-bottom: 2.5rem;
  font-size: 1.05rem;
}

/* ── Table of Contents ── */
.toc {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem 1.75rem;
  margin-bottom: 2.5rem;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.toc-title {
  font-family: 'Space Grotesk', ui-sans-serif, system-ui, sans-serif;
  font-weight: 700;
  font-size: 1.05rem;
  margin-bottom: 0.75rem;
  color: var(--text);
}

.toc-list {
  list-style: decimal;
  padding-left: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.toc-list a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.92rem;
  transition: color 0.2s;
}

.toc-list a:hover {
  color: var(--accent-strong);
  text-decoration: underline;
}

.toc-list a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 2px;
}

/* ── Cards ── */
.sections {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.card h2 {
  font-family: 'Space Grotesk', ui-sans-serif, system-ui, sans-serif;
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--accent);
  margin-bottom: 0.85rem;
}

.card p {
  color: var(--muted-strong);
  margin-bottom: 0.75rem;
}

.card p:last-child {
  margin-bottom: 0;
}

.card ul {
  color: var(--muted-strong);
  padding-left: 1.25rem;
  margin-bottom: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.card ul:last-child {
  margin-bottom: 0;
}

.card a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  font-weight: 500;
  transition: color 0.2s;
}

.card a:hover {
  color: var(--accent-strong);
}

.card a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 2px;
}

strong {
  color: var(--text);
  font-weight: 600;
}

/* ── Footer ── */
.footer {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.footer-brand {
  font-family: 'Space Grotesk', ui-sans-serif, system-ui, sans-serif;
  font-weight: 700;
  color: var(--text);
  font-size: 0.95rem;
}

.footer a {
  color: var(--accent);
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}

.footer a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 2px;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
}

/* ── Responsive ── */
@media (max-width: 480px) {
  .shell {
    padding: 2rem 0 3rem;
  }

  .card {
    padding: 1.25rem;
  }

  .toc {
    padding: 1.25rem;
  }

  .header {
    gap: 0.5rem;
  }
}

/* ── Accessibility ── */
@media (prefers-reduced-motion: reduce) {
  * {
    transition: none !important;
    animation: none !important;
  }

  html {
    scroll-behavior: auto;
  }
}

/* Focus visible only for keyboard */
:focus:not(:focus-visible) {
  outline: none;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 2px;
}