/* ═══════════════════════════════════════════════
   nav.css — navbar, sidebar, layout shell
   ═══════════════════════════════════════════════ */

/* ── Navbar ───────────────────────────────────── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  background: rgba(12, 14, 19, 0.90);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  z-index: 100;
  display: flex;
  align-items: center;
  padding: 0 1.4rem;
  gap: 1rem;
}
[data-theme="light"] .nav {
  background: rgba(242, 244, 249, 0.94);
}

/* Brand / logo ───────────────────────────────── */
.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text);
  text-decoration: none;
  user-select: none;
}
.nav-brand:hover { text-decoration: none; color: var(--text); }

.nav-logo {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  flex-shrink: 0;
  object-fit: cover;
  display: block;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}

.nav-links a {
  font-size: 0.875rem;
  color: var(--text2);
  padding: 5px 11px;
  border-radius: var(--radius-sm);
  transition: all 0.18s;
  display: flex;
  align-items: center;
  gap: 6px;
  text-decoration: none;
}

.nav-links a:hover {
  color: var(--text);
  background: var(--bg3);
}

.nav-links a .nf,
.theme-btn .nf { font-size: 1.24rem; }

.theme-btn {
  background: var(--bg3);
  border: 1px solid var(--border);
  color: var(--text2);
  cursor: pointer;
  padding: 5px 11px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-family: var(--font);
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all 0.18s;
  line-height: 1;
}
.theme-btn:hover {
  color: var(--text);
  border-color: var(--border2);
}

.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text2);
  padding: 6px;
  font-family: var(--nf);
  font-size: 1.2rem;
  line-height: 1;
}

/* ── Layout shell ─────────────────────────────── */
.layout {
  display: flex;
  padding-top: var(--nav-h);
  min-height: 100vh;
}

/* ── Sidebar ──────────────────────────────────── */
.sidebar {
  width: var(--sidebar-w);
  flex-shrink: 0;
  position: fixed;
  top: var(--nav-h);
  left: 0;
  bottom: 0;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  overflow-x: hidden;
  border-right: 1px solid var(--border);
  background: var(--bg2);
  padding: 1.4rem 0 0;
  transition: transform 0.24s ease;
  z-index: 80;
}
.sidebar::-webkit-scrollbar       { width: 3px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--border2); border-radius: 2px; }

.sidebar-section { margin-bottom: 1.4rem; }

.sidebar-label {
  font-size: 0.69rem;
  font-weight: 600;
  color: var(--text3);
  text-transform: uppercase;
  letter-spacing: 0.09em;
  padding: 0 1.1rem;
  margin-bottom: 0.4rem;
  display: flex;
  align-items: center;
  gap: 6px;
}

.sidebar-link {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 6px 1.1rem;
  font-size: 0.875rem;
  color: var(--text2);
  transition: all 0.14s;
  border-left: 2px solid transparent;
  text-decoration: none;
  user-select: none;
}
.sidebar-link:hover {
  color: var(--text);
  background: var(--accent-dim);
  border-left-color: var(--accent);
  text-decoration: none;
}
.sidebar-link.active {
  color: var(--accent2);
  background: var(--accent-dim);
  border-left-color: var(--accent);
  font-weight: 500;
}

/* icon inside sidebar links */
.sidebar-link .nf {
  color: var(--text3);
  font-size: 1.36rem;
  width: 26px;
  text-align: center;
  flex-shrink: 0;
}
.sidebar-link:hover .nf,
.sidebar-link.active .nf { color: var(--accent2); }

.sidebar-link[data-page="faq"] .nf {
  font-size: 0.9rem;
}

.sidebar-badge {
  font-size: 0.67rem;
  padding: 1px 6px;
  border-radius: 3px;
  font-weight: 600;
  margin-left: auto;
  font-family: var(--mono);
}
.badge-alpha { background: var(--amber-dim); color: var(--amber); }
.badge-new   { background: var(--accent-dim); color: var(--accent2); }

/* ── Main content area ────────────────────────── */
.main {
  margin-left: var(--sidebar-w);
  flex: 1;
  min-width: 0;
}

.content-area {
  max-width: 820px;
  padding: 3rem 3.5rem;
  margin: 0 auto;
}

/* ── Page headings ────────────────────────────── */
.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.4rem;
  display: flex;
  align-items: center;
  gap: 10px;
}
.section-title .nf { color: var(--accent2); font-size: 1.72rem; }

.section-sub {
  color: var(--text2);
  margin-bottom: 2rem;
  font-size: 0.92rem;
}

.sub-h {
  font-size: 0.96rem;
  font-weight: 600;
  margin: 2rem 0 0.75rem;
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text);
}
.sub-h .nf { color: var(--accent2); font-size: 1.34rem; }

/* ── Sidebar overlay (mobile) ─────────────────── */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  z-index: 70;
}

/* ── page-body wrapper (hidden until JS moves it) */
#page-body { display: contents; }

/* ── Page transitions ─────────────────────────── */
.main .content-area {
  animation: fadeUp 0.22s ease both;
  transition: opacity 0.14s ease;
}

.page-transition-overlay {
  position: fixed;
  inset: 0;
  background: var(--bg);
  opacity: 0;
  pointer-events: none;
  z-index: 120;
  transition: opacity 0.22s ease;
}

body.page-leave .page-transition-overlay {
  opacity: 1;
}

@media (prefers-reduced-motion: reduce) {
  .main .content-area {
    transition: none;
    animation: none;
  }
  .page-transition-overlay {
    transition: none;
    opacity: 0;
  }
}

/* ── Mobile ───────────────────────────────────── */
@media (max-width: 768px) {
  .hamburger { display: flex; }

  .sidebar {
    transform: translateX(-100%);
    z-index: 95;
  }
  .sidebar.open { transform: translateX(0); }
  .sidebar-overlay.open { display: block; }

  .main { margin-left: 0; }
  .content-area { padding: 2rem 1.4rem; }
  .nav-links a span:not(.nf) { display: none; }
}

/* ── Ko-fi button (navbar) ────────────────────── */
.kofi-btn {
  font-size: 0.875rem;
  color: var(--text2) !important;
  padding: 5px 11px;
  border-radius: var(--radius-sm);
  transition: all 0.18s;
  display: flex;
  align-items: center;
  gap: 6px;
  border: none;
  background: transparent;
}
.kofi-btn:hover {
  background: var(--bg3);
  text-decoration: none;
  color: var(--text) !important;
}
.kofi-btn .nf { font-size: 1.24rem; }

/* ── Ko-fi card (sidebar bottom) ─────────────── */
.sidebar-kofi {
  margin-top: auto;
  padding: 0.55rem 0.8rem 0.55rem;
  border-top: 1px solid var(--border);
  background: var(--bg2);
  position: sticky;
  bottom: 0;
  z-index: 1;
}

.sidebar-kofi-link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0.55rem 0.7rem;
  border-radius: var(--radius);
  background: var(--accent-dim);
  border: 1px solid rgba(124, 106, 245, 0.28);
  text-decoration: none;
  transition: all 0.18s;
}
.sidebar-kofi-link:hover {
  background: rgba(124, 106, 245, 0.2);
  border-color: rgba(124, 106, 245, 0.48);
  text-decoration: none;
  transform: translateY(-1px);
}
.sidebar-kofi-link .nf {
  font-size: 1.34rem;
  color: var(--accent2);
  flex-shrink: 0;
}

.sidebar-kofi-title {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent2);
  line-height: 1.15;
}
.sidebar-kofi-sub {
  font-size: 0.66rem;
  color: var(--text3);
  margin-top: 1px;
}