@media(min-width:1101px){
  .site-header.wrap{--header-expanded-height:98px;position:sticky;top:0;z-index:30;background:#f7f5ef;width:100%;max-width:none;margin-inline:0;padding-inline:max(56px,calc((100% - 1280px)/2));transition:transform .2s ease}
  .site-header.wrap.is-scrolled{height:72px;margin-bottom:calc(var(--header-expanded-height) - 72px)}
  .site-header.wrap.is-hidden{transform:translateY(-100%)}
}
@media(min-width:1101px) and (max-width:1150px){
  .site-header.wrap{padding-inline:32px}
}

@media(min-width:1101px) and (prefers-reduced-motion:reduce){.site-header.wrap{transition:none}}

/* The pinned book owns the viewport while its scroll-driven scene is active. */
body:has(.journal-scroll-track.is-scrolling .journal-scroll-hint.is-active) .site-header.wrap{
  transform:translateY(-100%);visibility:hidden;pointer-events:none
}

/* Focused desktop courses lock page scrolling, so navigation stays visible. */
@media(min-width:1101px){
  body.course-open .site-header.wrap{position:fixed;inset:0 0 auto;transform:none;transition:none}
  body.course-open .site-header.wrap + main{padding-top:98px}
}

@media(min-width:1101px){
  body.course-open:has(.site-header.is-scrolled) .atlas-explorer{top:84px}
}