/* ── NAV ── */
nav {
  position:fixed; top:0; left:0; right:0; z-index:100;
  display:flex; align-items:center; justify-content:space-between;
  padding:1.2rem 4rem;
  background: rgba(245,240,232,0.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}

.nav-logo { display:flex; align-items:center; gap:1rem; text-decoration:none; }

.logo-mark {
  width:42px; height:42px;
  display:flex; align-items:center; justify-content:center;
}
.logo-mark svg { width:100%; height:100%; }

.logo-text-zh {
  font-family:'Noto Serif SC', serif;
  font-size:1.4rem; font-weight:600;
  color:var(--ink); letter-spacing:0.05em;
}
.logo-text-en {
  font-family:'IBM Plex Mono', monospace;
  font-size:0.6rem; letter-spacing:0.25em;
  color:var(--signal); text-transform:uppercase;
  display:block; margin-top:1px;
}

.nav-center {
  display:flex; gap:3rem; list-style:none;
}
.nav-center a {
  color:var(--muted); text-decoration:none;
  font-size:0.68rem; letter-spacing:0.12em;
  text-transform:uppercase; transition:color 0.2s;
  position:relative;
}
.nav-center a::after {
  content:''; position:absolute;
  bottom:-3px; left:0; right:0; height:1px;
  background:var(--signal);
  transform:scaleX(0); transition:transform 0.2s;
}
.nav-center a:hover { color:var(--signal); }
.nav-center a:hover::after { transform:scaleX(1); }

.nav-right { display:flex; align-items:center; gap:1rem; }

.lang-pill {
  display:flex; gap:1px;
  background:var(--parchment);
  border:1px solid var(--border);
  border-radius:2px; padding:2px;
}
.lang-btn {
  background:none; border:none;
  padding:4px 10px;
  font-family:'IBM Plex Mono', monospace;
  font-size:0.6rem; letter-spacing:0.1em;
  color:var(--muted); cursor:pointer;
  border-radius:1px; transition:all 0.15s;
}
.lang-btn.active { background:var(--ink); color:var(--cream); }

.nav-login {
  background:none; border:1px solid var(--ink3);
  padding:0.45rem 1.1rem;
  font-family:'IBM Plex Mono', monospace;
  font-size:0.62rem; letter-spacing:0.12em;
  text-transform:uppercase; color:var(--ink3);
  cursor:pointer; border-radius:2px; transition:all 0.2s;
}
.nav-login:hover { background:var(--ink); color:var(--cream); }

@media(max-width:900px) {
  nav { padding:1rem 1.5rem; }
  .nav-center { display:none; }
}