.site-header{position:sticky;top:0;z-index:50;background:var(--surface);border-bottom:1px solid var(--line)}
.site-header__bar{position:relative;display:flex;align-items:center;justify-content:space-between;min-height:68px}
.logo{display:inline-flex;align-items:center;gap:.7rem;font-weight:700;font-size:1.15rem;color:var(--ink);text-decoration:none}
.logo__mark{display:grid;place-items:center;width:38px;height:38px;border-radius:9px;background:var(--navy);color:#fff;font-size:.85rem;letter-spacing:.02em}
.nav__list{display:flex;gap:.3rem}
.nav__link{display:block;padding:.55rem .95rem;border-radius:var(--radius-sm);font-weight:500;color:var(--ink-soft);text-decoration:none;transition:background .15s,color .15s}
.nav__link:hover{background:var(--sky);color:var(--ink)}
.burger{display:none;width:48px;height:48px;border:1px solid var(--line);border-radius:var(--radius-sm);background:var(--surface);cursor:pointer;flex-direction:column;justify-content:center;align-items:center;gap:6px;padding:0}
.burger span{display:block;width:22px;height:2px;background:var(--ink)}
@media (max-width:820px){
  .burger{display:flex}
  .nav{position:absolute;left:0;right:0;top:100%;display:none;background:var(--surface);border:1px solid var(--line);border-radius:0 0 var(--radius) var(--radius);box-shadow:var(--shadow-md);padding:.6rem}
  .nav.is-open{display:block}
  .nav__list{flex-direction:column}
  .nav__link{padding:.85rem 1rem}
}

.logo__text{display:flex;flex-direction:column;line-height:1.15}
.logo__name{font-size:1.05rem}
.logo__sub{font-size:.78rem;font-weight:500;color:var(--ink-soft)}
@media (max-width:640px){.logo__name span{display:block}.logo__sub{display:none}}