.nav-orb {
  position: fixed;
  bottom: 28px; right: 28px;
  z-index: 1000;
  width: 46px; height: 46px;
  border-radius: 2px;
  background: var(--text);
  border: 1px solid var(--border);
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 4px 20px var(--shadow-float);
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease), background 0.35s;
  -webkit-tap-highlight-color: transparent;
  user-select: none; outline: none;
  color: var(--bg);
}
.nav-orb:hover {
  transform: scale(1.06);
  box-shadow: 0 8px 28px var(--shadow-panel);
}

/* Full-screen overlay */
.nav-overlay {
  position: fixed; inset: 0; z-index: 999;
  background: var(--bg);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 40px; opacity: 0; pointer-events: none;
  transition: opacity 0.3s var(--ease);
}
.nav-overlay.open { opacity: 1; pointer-events: all; }

.nav-links { list-style: none; text-align: center; display: flex; flex-direction: column; gap: 2px; }

.nav-link-item {
  opacity: 0; transform: translateY(16px);
  transition: opacity 0.28s var(--ease), transform 0.28s var(--ease);
}
.nav-overlay.open .nav-link-item { opacity: 1; transform: none; }
.nav-overlay.open .nav-link-item:nth-child(1) { transition-delay: 0.04s; }
.nav-overlay.open .nav-link-item:nth-child(2) { transition-delay: 0.08s; }
.nav-overlay.open .nav-link-item:nth-child(3) { transition-delay: 0.12s; }
.nav-overlay.open .nav-link-item:nth-child(4) { transition-delay: 0.16s; }
.nav-overlay.open .nav-link-item:nth-child(5) { transition-delay: 0.20s; }
.nav-overlay.open .nav-link-item:nth-child(6) { transition-delay: 0.24s; }

.nav-link {
  font-family: 'Instrument Serif', serif;
  font-size: clamp(2.4rem, 5.5vw, 4.4rem);
  font-weight: 400;
  color: var(--text);
  text-decoration: none;
  line-height: 1.2;
  display: inline-block;
  padding: 4px 12px;
  transition: color 0.15s;
  position: relative;
}
.nav-link:hover { color: var(--red); }
.nav-number {
  font-family: 'Geist Mono', monospace;
  font-size: 0.65rem;
  color: var(--text-dim);
  vertical-align: super;
  margin-right: 5px;
}

/* Theme toggle */
.nav-theme-row {
  opacity: 0; transform: translateY(10px);
  transition: opacity 0.28s var(--ease) 0.26s, transform 0.28s var(--ease) 0.26s;
}
.nav-overlay.open .nav-theme-row { opacity: 1; transform: none; }
.nav-theme-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 16px;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 2px;
  color: var(--text-sub);
  cursor: pointer;
  font-family: 'Geist Mono', monospace;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  transition: color 0.2s, border-color 0.2s;
}
@media (min-width: 769px) {
  .nav-orb {
    width: 54px; height: 54px;
    bottom: 32px; right: 32px;
  }
}

@media (max-width: 768px) {
  .nav-orb { bottom: 20px; right: 20px; }
}
.nav-theme-btn:hover { color: var(--red); border-color: var(--red); }