header{
  position:sticky;top:0;z-index:80;
  background:rgba(246,245,242,0.88);
  backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line);
}
.nav{display:flex;align-items:center;justify-content:space-between;height:80px;gap:20px;}
.nav-panel{display:contents;}
.nav-actions{display:flex;align-items:center;gap:10px;}
.brandmark{display:flex;align-items:center;gap:16px;}
.brandmark img{width:auto;}
.brandmark img:first-of-type{height:40px;}
.brandmark img:last-of-type{height:22px;}
.brandmark .sep{width:1px;height:24px;background:var(--line-strong);}
.nav-links{display:flex;align-items:center;gap:30px;font-size:0.9rem;color:var(--ink-soft);}
.nav-links a{transition:color .16s ease;}
.nav-links a:hover{color:var(--ink);}
.nav-toggle{
  display:none;
  position:relative;
  z-index:100;
  width:44px;height:44px;
  align-items:center;justify-content:center;
  flex-direction:column;gap:5px;
  border:none;background:none;cursor:pointer;padding:0;
  flex-shrink:0;
}
.nav-toggle-bar{
  display:block;width:22px;height:2px;
  background:var(--ink);border-radius:2px;
  transition:transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:first-child{transform:translateY(3.5px) rotate(45deg);}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:last-child{transform:translateY(-3.5px) rotate(-45deg);}
.nav-backdrop{
  position:fixed;inset:0;z-index:70;
  background:rgba(28,28,28,0.35);
  opacity:0;
  visibility:hidden;
  pointer-events:none;
  transition:opacity var(--dur) var(--ease), visibility 0s var(--dur);
}
.nav-backdrop.is-open{
  opacity:1;
  visibility:visible;
  pointer-events:auto;
  transition:opacity var(--dur) var(--ease), visibility 0s 0s;
}
@media(max-width:900px){
  header{backdrop-filter:none;background:var(--bg);}
  .nav{height:68px;}
  .nav-toggle{display:flex;}
  .nav-panel{
    display:flex;flex-direction:column;
    position:fixed;top:0;right:0;bottom:0;
    width:min(86vw,340px);
    z-index:95;
    background:var(--surface);
    border-left:1px solid var(--line);
    padding:84px 24px 32px;
    gap:8px;
    overflow-y:auto;
    overscroll-behavior:contain;
    transform:translateX(101%);
    visibility:hidden;
    transition:transform .28s var(--ease), visibility 0s .28s;
  }
  .nav-panel.is-open{
    transform:none;
    visibility:visible;
    transition:transform .28s var(--ease), visibility 0s 0s;
  }
  .nav-links{
    flex-direction:column;align-items:stretch;gap:0;
    font-size:1rem;
  }
  .nav-links a{
    display:flex;align-items:center;min-height:48px;
    padding:0 4px;
    color:var(--ink);
    border-bottom:1px solid var(--line);
  }
  .nav-actions{
    flex-direction:column;align-items:stretch;gap:10px;
    margin-top:24px;
  }
  .nav-actions .btn{width:100%;min-height:48px;}
  .lang-switch{align-self:flex-start;}
}
@media(min-width:901px){
  .nav-panel{transform:none;}
  .nav-backdrop{display:none;}
}