:root {
  color-scheme: dark;
  --portal-bg: #0b0f19;
  --portal-panel: #111827;
  --portal-panel-raised: #151e2d;
  --portal-border: #1f293d;
  --portal-accent: #00f0ff;
  --portal-accent-glow: rgba(0, 240, 255, 0.2);
  --portal-text: #f3f4f6;
  --portal-muted: #9ca3af;
}

html {
  min-height: 100%;
  font-size: 16px;
}

body {
  min-width: 320px;
  min-height: 100vh;
  margin: 0;
  background: var(--portal-bg);
  color: var(--portal-text);
  font-family: 'Inter', sans-serif;
  line-height: 1.6;
}

a {
  color: var(--portal-accent);
}

a:hover {
  color: #8cf8ff;
}

.portal-shell {
  display: flex;
  min-height: 100vh;
}

.sidebar {
  position: sticky;
  top: 0;
  display: flex;
  width: 258px;
  height: 100vh;
  flex: 0 0 258px;
  flex-direction: column;
  padding: 1.75rem 1.2rem 1.25rem;
  border-right: 1px solid var(--portal-border);
  background: #0d121e;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin-bottom: 3.25rem;
  color: var(--portal-text);
  text-decoration: none;
}

.brand:hover {
  color: #fff;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  flex: 0 0 42px;
  place-items: center;
  border: 1px solid rgba(0, 240, 255, 0.4);
  border-radius: 12px;
  background: rgba(0, 240, 255, 0.08);
  color: var(--portal-accent);
  font-family: 'Fira Code', monospace;
  font-size: 0.85rem;
  font-weight: 600;
}

.brand-name,
.brand-caption {
  display: block;
}

.brand-name {
  font-size: 0.95rem;
  font-weight: 700;
}

.brand-caption {
  margin-top: 0.15rem;
  color: var(--portal-muted);
  font-family: 'Fira Code', monospace;
  font-size: 0.62rem;
  letter-spacing: 0.1em;
}

.nav-heading {
  margin: 0 0 0.65rem 0.7rem;
  color: #687386;
  font-family: 'Fira Code', monospace;
  font-size: 0.67rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.primary-nav {
  display: grid;
  gap: 0.35rem;
}

.primary-nav .nav-link {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  padding: 0.72rem 0.75rem;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--portal-muted);
  font-size: 0.9rem;
  transition: color 0.2s ease, background-color 0.2s ease, border-color 0.2s ease;
}

.primary-nav .nav-link:hover,
.primary-nav .nav-link:focus-visible {
  border-color: var(--portal-border);
  background: rgba(255, 255, 255, 0.03);
  color: var(--portal-text);
}

.primary-nav .nav-link.active {
  border-color: rgba(0, 240, 255, 0.16);
  background: rgba(0, 240, 255, 0.08);
  color: var(--portal-accent);
}

.nav-index {
  color: #687386;
  font-family: 'Fira Code', monospace;
  font-size: 0.7rem;
}

.active .nav-index {
  color: var(--portal-accent);
}

.sidebar-status {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  margin-top: auto;
  padding: 0.9rem 0.2rem 0;
  border-top: 1px solid var(--portal-border);
  color: var(--portal-muted);
  font-size: 0.76rem;
}

.status-indicator {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--portal-accent);
  box-shadow: 0 0 10px var(--portal-accent-glow);
}

.status-separator {
  padding: 0 0.15rem;
  color: #566174;
}

.portal-main {
  display: flex;
  min-width: 0;
  flex: 1;
  flex-direction: column;
}

.topbar {
  position: relative;
  z-index: 2;
  display: flex;
  min-height: 72px;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.8rem clamp(1rem, 3vw, 2.5rem);
  border-bottom: 1px solid var(--portal-border);
  background: rgba(11, 15, 25, 0.88);
}

.page-context {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--portal-text);
  font-size: 0.9rem;
  font-weight: 600;
}

.context-mark {
  color: var(--portal-accent);
  font-family: 'Fira Code', monospace;
}

.language-toggle {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.45rem 0.7rem;
  border: 1px solid var(--portal-border);
  border-radius: 8px;
  background: var(--portal-panel);
  color: var(--portal-text);
  font-size: 0.8rem;
}

.language-toggle::after {
  margin-left: 0.2rem;
  color: var(--portal-muted);
}

.language-toggle:hover,
.language-toggle:focus-visible {
  border-color: var(--portal-accent);
  color: var(--portal-text);
}

.language-indicator {
  color: var(--portal-accent);
  font-family: 'Fira Code', monospace;
  font-weight: 600;
}

.language-menu {
  min-width: 10rem;
  padding: 0.35rem;
  border: 1px solid var(--portal-border);
  background: var(--portal-panel);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
}

.language-menu form {
  margin: 0;
}

.language-menu .dropdown-item {
  border-radius: 5px;
  color: var(--portal-muted);
  font-size: 0.85rem;
}

.language-menu .dropdown-item:hover,
.language-menu .dropdown-item:focus {
  background: var(--portal-panel-raised);
  color: var(--portal-accent);
}

.content-shell {
  width: 100%;
  flex: 1;
  padding: 1.5rem clamp(1rem, 3vw, 2.5rem);
}

.portal-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.55rem;
  padding: 1rem clamp(1rem, 3vw, 2.5rem);
  border-top: 1px solid var(--portal-border);
  color: #7f8a9c;
  font-size: 0.75rem;
}

.footer-divider {
  color: var(--portal-accent);
  font-family: 'Fira Code', monospace;
}

.home-page,
.content-page,
.error-page {
  position: relative;
  max-width: 1100px;
  margin: 0 auto;
  padding: clamp(1.4rem, 4vw, 3rem);
  overflow: hidden;
  border: 1px solid var(--portal-border);
  border-radius: 16px;
  background:
    radial-gradient(ellipse at 85% 0%, rgba(0, 240, 255, 0.08), transparent 45%),
    var(--portal-panel);
}

.eyebrow {
  margin: 0 0 0.85rem;
  color: var(--portal-accent);
  font-family: 'Fira Code', monospace;
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.home-page h1,
.content-page h1,
.error-page h1 {
  margin: 0 0 1rem;
  color: var(--portal-text);
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 800;
  letter-spacing: -0.045em;
}

.home-page h1 {
  background: linear-gradient(90deg, #fff, var(--portal-accent));
  background-clip: text;
  color: transparent;
  -webkit-background-clip: text;
}

.home-intro,
.content-page p,
.error-page p {
  max-width: 720px;
  color: var(--portal-muted);
}

.home-intro {
  margin: 0;
  font-size: 1.05rem;
}

.home-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 230px), 1fr));
  gap: 1rem;
  margin-top: 2.25rem;
}

.home-link-card {
  display: flex;
  min-height: 130px;
  flex-direction: column;
  justify-content: space-between;
  padding: 1.1rem 1.2rem;
  border: 1px solid var(--portal-border);
  border-radius: 12px;
  background: rgba(11, 15, 25, 0.56);
  color: var(--portal-text);
  text-decoration: none;
  transition: transform 0.2s ease, border-color 0.2s ease, background-color 0.2s ease;
}

.home-link-card:hover,
.home-link-card:focus-visible {
  transform: translateY(-2px);
  border-color: var(--portal-accent);
  background: rgba(0, 240, 255, 0.04);
  color: var(--portal-text);
}

.home-link-card span:first-child {
  color: var(--portal-accent);
  font-family: 'Fira Code', monospace;
  font-size: 0.75rem;
}

.home-link-card strong {
  font-size: 1.05rem;
}

.content-page {
  min-height: 260px;
}

.content-page h1 {
  font-size: clamp(1.8rem, 4vw, 2.5rem);
}

.error-page h1 {
  color: #fca5a5;
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--portal-accent);
  outline-offset: 3px;
}

@media (max-width: 760px) {
  .portal-shell {
    flex-direction: column;
  }

  .sidebar {
    position: static;
    width: 100%;
    height: auto;
    flex: 0 0 auto;
    padding: 0.75rem 1rem;
    border-right: 0;
    border-bottom: 1px solid var(--portal-border);
  }

  .brand {
    margin-bottom: 0.8rem;
  }

  .brand-mark {
    width: 36px;
    height: 36px;
    flex-basis: 36px;
  }

  .nav-heading,
  .sidebar-status {
    display: none;
  }

  .primary-nav {
    display: flex;
    gap: 0.35rem;
    overflow-x: auto;
  }

  .primary-nav .nav-link {
    flex: 0 0 auto;
    gap: 0.45rem;
    padding: 0.48rem 0.65rem;
    font-size: 0.8rem;
  }

  .topbar {
    min-height: 60px;
  }
}

@media (max-width: 420px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.65rem;
    padding-top: 0.75rem;
    padding-bottom: 0.75rem;
  }

  .language-toggle {
    padding: 0.35rem 0.55rem;
  }

  .portal-footer {
    gap: 0.35rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}