#nav {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; gap: 18px;
  padding: 12px 24px;
  background: color-mix(in srgb, var(--canvas) 82%, transparent);
  backdrop-filter: saturate(1.2) blur(12px);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 9px; }
.brand-mark { display: grid; place-items: center; width: 30px; height: 30px; border-radius: 9px; background: var(--brand); color: #04211d; }
:root[data-theme='light'] .brand-mark { color: #fff; }
.brand-name { font-family: var(--display); font-weight: 800; font-size: 19px; letter-spacing: -0.03em; }
.brand-tag { font-family: var(--mono); font-size: 10px; letter-spacing: 0.6px; color: var(--fg-faint); border-left: 1px solid var(--line-2); padding-left: 9px; margin-left: 2px; }
@media (max-width: 1000px) { .brand-tag { display: none; } }

.tabs { display: flex; gap: 2px; margin-left: 8px; }
.tab { display: inline-flex; align-items: center; gap: 7px; padding: 8px 13px; border-radius: var(--r-sm); color: var(--fg-muted); font-weight: 500; font-size: 14px; transition: all 0.16s; }
.tab svg { color: var(--fg-faint); transition: color 0.16s; }
.tab:hover { color: var(--fg); background: var(--surface); }
.tab.is-active { color: var(--fg); background: var(--surface); }
.tab.is-active svg { color: var(--brand); }

.nav-right { display: flex; align-items: center; gap: 8px; margin-left: auto; }
.lang-btn { width: auto; padding: 0 11px; }
.lang-code { font-family: var(--mono); font-size: 11px; font-weight: 600; }
.offline-pill { display: inline-flex; align-items: center; gap: 7px; font-size: 11.5px; color: var(--warn); background: var(--warn-tint); border: 1px solid color-mix(in srgb, var(--warn) 40%, transparent); padding: 5px 10px; border-radius: 20px; }
.menu-btn { display: none; }

@media (max-width: 860px) {
  .menu-btn { display: inline-flex; }
  .tabs { position: absolute; top: 100%; left: 0; right: 0; flex-direction: column; gap: 4px; padding: 12px 16px; background: var(--surface); border-bottom: 1px solid var(--line); box-shadow: var(--shadow); transform: translateY(-8px); opacity: 0; pointer-events: none; transition: all 0.18s var(--ease); }
  #nav.menu-open .tabs { transform: translateY(0); opacity: 1; pointer-events: auto; }
  .tab { padding: 12px 14px; }
  .offline-pill span { display: none; }
}
@media (max-width: 480px) { .brand-name { font-size: 17px; } .nav-right { gap: 5px; } }