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

:root {
  --bg: #0e0c18;
  --surface: #1a1730;
  --surface2: #1e1a36;
  --border: #2a2647;
  --accent: #6c63ff;
  --accent-hover: #5a52e0;
  --text: #f8f8fc;
  --text-muted: #9692aa;
  --text-dim: #4a4563;
  --text-secondary: #c4c1d8;
  --mark-cutout-color: #0e0c18;
  --radius: 12px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
  --transition: 180ms ease;
}

[data-theme="light"] {
  --bg: #fcfbff;
  --surface: #ffffff;
  --surface2: #edeaf7;
  --border: #e2dff0;
  --accent: #6c63ff;
  --accent-hover: #5a52e0;
  --text: #18142a;
  --text-muted: #9692aa;
  --text-dim: #4a4563;
  --text-secondary: #4a4563;
  --mark-cutout-color: #fcfbff;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
}

body {
  font-family:
    "Outfit",
    "Inter",
    system-ui,
    -apple-system,
    sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

/* ── Header ── */
header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  padding: 0 24px;
  height: 64px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
}
:root header {
  background: rgba(14, 12, 24, 0.9);
}
[data-theme="light"] header {
  background: rgba(252, 251, 255, 0.9);
}
.header-inner {
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 14px;
}
.logo-full {
  height: 36px;
  width: auto;
  flex-shrink: 0;
}
header a.logo-link {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text);
}
header a.logo-link:hover {
  text-decoration: none;
}

.theme-toggle {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition);
  margin-left: auto;
}
.theme-toggle:hover {
  border-color: var(--accent);
  color: var(--text);
}
.theme-toggle svg {
  width: 16px;
  height: 16px;
}
.theme-toggle .icon-moon,
[data-theme="light"] .theme-toggle .icon-sun {
  display: none;
}
[data-theme="light"] .theme-toggle .icon-moon {
  display: block;
}

/* ── Content ── */
.content {
  flex: 1;
  max-width: 740px;
  margin: 0 auto;
  padding: 48px 32px;
  width: 100%;
}
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 32px;
}
.content h2 {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 8px;
}
.content .subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 40px;
}
.content h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-top: 36px;
  margin-bottom: 12px;
}
.content p {
  line-height: 1.7;
  color: var(--text-muted);
  margin-bottom: 16px;
}
.content ul {
  list-style: none;
  padding: 0;
  margin-bottom: 16px;
}
.content ul li {
  position: relative;
  padding-left: 16px;
  line-height: 1.7;
  color: var(--text-muted);
  margin-bottom: 6px;
}
.content ul li::before {
  content: "";
  position: absolute;
  left: 0.25rem;
  top: 0.65rem;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
}
.highlight-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin: 24px 0;
}
.highlight-box p {
  margin-bottom: 0;
}

/* ── Footer ── */
footer {
  border-top: 1px solid var(--border);
  padding: 24px;
  background: var(--surface);
  margin-top: auto;
}
.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.footer-left {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.8rem;
  color: var(--text-muted);
}
.footer-logo {
  height: 24px;
  width: auto;
}
footer a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.75rem;
  transition: color var(--transition);
}
footer a:hover {
  color: var(--accent);
  text-decoration: none;
}
footer .footer-links {
  display: flex;
  gap: 24px;
}

@media (max-width: 600px) {
  header {
    padding: 0 16px;
  }
  .content {
    padding: 32px 20px;
  }
  .content h2 {
    font-size: 1.5rem;
  }
  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
}