/* ═══════════════════════════ TOP NAV (glass) ═══════════════════════════ */
#top-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  background: var(--nav-bg);
  backdrop-filter: saturate(1.8) blur(14px);
  -webkit-backdrop-filter: saturate(1.8) blur(14px);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  z-index: 2000;
  gap: 16px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex-shrink: 0;
}
.nav-brand svg { filter: drop-shadow(0 0 10px var(--accent-glow)); }
.brand-name {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.02em;
}
.nav-brand:hover { text-decoration: none; }

/* ── Desktop nav links ────────────────────────────────────── */
.nav-links {
  display: flex;
  align-items: center;
  gap: 2px;
  flex: 1;
  justify-content: center;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0 14px;
  height: 36px;
  border-radius: var(--radius);
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
  transition: background 0.15s, color 0.15s;
  white-space: nowrap;
}
.nav-link:hover { background: var(--surface); color: var(--text); text-decoration: none; }
.nav-link.active { background: var(--accent-soft); color: var(--accent); }

/* ── Nav right side (theme toggle + burger) ──────────────── */
.nav-right {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

/* ── Theme toggle ─────────────────────────────────────────── */
#theme-toggle {
  width: 36px; height: 36px;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
  flex-shrink: 0;
  padding: 0;
}
#theme-toggle:hover {
  color: var(--accent);
  border-color: var(--accent-ring);
  background: var(--accent-soft);
}
#theme-toggle .icon-sun  { display: none; }
#theme-toggle .icon-moon { display: block; }
[data-theme="light"] #theme-toggle .icon-sun  { display: block; }
[data-theme="light"] #theme-toggle .icon-moon { display: none; }

/* ── Burger button ────────────────────────────────────────── */
#burger-btn {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  color: var(--text-muted);
  transition: background 0.15s, color 0.15s, border-color 0.15s;
  flex-shrink: 0;
  padding: 0;
}
#burger-btn:hover { background: var(--surface); color: var(--text); border-color: var(--border-strong); }

#burger-btn span {
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  transition: transform 0.25s ease, opacity 0.2s ease;
  transform-origin: center;
}

/* Burger → X animation when nav is open */
body.nav-open #burger-btn span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
body.nav-open #burger-btn span:nth-child(2) { opacity: 0; transform: scaleX(0); }
body.nav-open #burger-btn span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ── Backdrop ─────────────────────────────────────────────── */
#nav-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  z-index: 1800;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s;
}
body.nav-open #nav-backdrop {
  opacity: 1;
  pointer-events: all;
}

/* ── Mobile/tablet drawer ─────────────────────────────────── */
#nav-drawer {
  position: fixed;
  top: var(--nav-h);
  left: 0;
  bottom: 0;
  width: 280px;
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  z-index: 1900;
  display: flex;
  flex-direction: column;
  padding: 12px;
  gap: 4px;
  transform: translateX(-100%);
  transition: transform 0.28s cubic-bezier(0.4, 0, 0.2, 1);
  overflow-y: auto;
  box-shadow: var(--shadow-lg);
}
body.nav-open #nav-drawer { transform: translateX(0); }

/* Drawer links — larger tap targets than desktop */
.drawer-link {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
  transition: background 0.15s, color 0.15s;
}
.drawer-link:hover  { background: var(--surface); color: var(--text); text-decoration: none; }
.drawer-link.active { background: var(--accent-soft); color: var(--accent); }
.drawer-link svg    { flex-shrink: 0; }

/* ── Responsive: show burger at tablet + mobile ───────────── */
@media (max-width: 1024px) {
  .nav-links { display: none; }
  #burger-btn { display: flex; }
}

@media (max-width: 640px) {
  #top-nav { padding: 0 12px; gap: 8px; }
  .brand-name { font-size: 13px; }
}

/* ── Pull-to-refresh indicator ────────────────────────────── */
#ptr-indicator {
  position: fixed;
  top: var(--nav-h);
  left: 50%;
  transform: translateX(-50%) translateY(-100%);
  z-index: 1999;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-top: none;
  border-radius: 0 0 var(--radius) var(--radius);
  box-shadow: var(--shadow-md);
  font-size: 12px;
  color: var(--text-muted);
  pointer-events: none;
  transition: transform 0.2s ease;
  white-space: nowrap;
}
#ptr-indicator.ptr-visible {
  transform: translateX(-50%) translateY(0);
}
#ptr-indicator .ptr-spinner {
  width: 14px;
  height: 14px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  flex-shrink: 0;
}
#ptr-indicator.ptr-loading .ptr-spinner {
  animation: ptr-spin 0.7s linear infinite;
}
@keyframes ptr-spin {
  to { transform: rotate(360deg); }
}
#ptr-indicator .ptr-arrow {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
  transition: transform 0.2s;
}
#ptr-indicator.ptr-ready .ptr-arrow {
  transform: rotate(180deg);
}