/* One masthead for the identity, sections and supporting material. Its footprint
   matches the original hero masthead; opening a menu never shifts the page. */
.atlas-layout .research-header {
  --nav-paper:0;
  --nav-paper-percent:0%;
  --nav-ink-blend:0%;
  --nav-ink:color-mix(in srgb,#e8ecdd,#fff var(--nav-ink-blend));
  --nav-muted:color-mix(in srgb,#bbc8b9,#fff var(--nav-ink-blend));
  --nav-rule:color-mix(in srgb,#dce8ce24,transparent var(--nav-paper-percent));
  position:fixed;
  inset:0 0 auto;
  z-index:30;
  color:var(--nav-ink);
  background:transparent;
  box-shadow:none;
  backdrop-filter:none;
  isolation:isolate;
  transition:none;
}
.atlas-layout .research-header::before {
  content:"";
  position:absolute;
  inset:0;
  z-index:-1;
  background:var(--paper);
  box-shadow:0 1px 0 var(--rule);
  opacity:var(--nav-paper);
  pointer-events:none;
}
.atlas-layout .research-header.is-reading {
  --nav-ink:color-mix(in srgb,#0b100c,#26382e var(--nav-ink-blend));
  --nav-muted:color-mix(in srgb,#0b100c,#626f61 var(--nav-ink-blend));
}
.atlas-layout .research-header .header-inner {
  display:flex;
  min-height:76px;
  gap:24px;
  align-items:center;
  border-top:0;
  border-bottom:1px solid var(--nav-rule);
}
.atlas-layout .publication-masthead { border-bottom:0; }
.atlas-layout .research-header .research-brand { flex:none; color:var(--nav-ink); transition:none; }
.atlas-layout .research-header .research-brand span { color:var(--nav-muted); transition:none; }
.navigation-panel { display:flex; align-self:stretch; align-items:stretch; gap:48px; margin-left:auto; }
.atlas-layout .research-header .page-nav { display:flex; width:auto; gap:32px; margin:0; min-height:0; align-self:stretch; background:none; }
.atlas-layout .research-header .page-nav a {
  display:flex;
  align-items:center;
  align-self:center;
  min-height:44px;
  position:relative;
  padding:0;
  max-width:none;
  font:14px/1.2 var(--sans);
  letter-spacing:0;
  color:var(--nav-muted);
  text-decoration:none;
  white-space:nowrap;
  transition:none;
}
.atlas-layout .research-header .page-nav a:hover,
.atlas-layout .research-header .page-nav a[aria-current] { color:var(--nav-ink); }
.atlas-layout .research-header .page-nav a::after {
  content:"";
  display:block;
  position:absolute;
  inset:auto auto 1px 0;
  width:24px;
  height:1px;
  background:currentColor;
  opacity:0;
  transform:scaleX(.4);
  transform-origin:left;
  transition:opacity .16s,transform .16s;
}
.atlas-layout .research-header .page-nav a[aria-current]::after,
.atlas-layout .research-header .page-nav a:hover::after { opacity:1; transform:scaleX(1); }
.research-header :is(a,button):focus-visible { outline:2px solid var(--nav-muted); outline-offset:6px; }
.publication-links { display:flex; align-items:center; gap:24px; }
.publication-links :is(a,.paper-forthcoming) { display:inline-flex; align-items:center; gap:6px; min-height:44px; color:var(--nav-muted); font:13px/1.2 var(--sans); white-space:nowrap; text-decoration:none; }
.publication-links a:hover { color:var(--nav-ink); }
.publication-links a > span { font-size:12px; opacity:.7; }
.navigation-toggle { display:none; }
@media(max-width:1000px) {
  .navigation-panel { gap:32px; }
  .publication-links { gap:20px; }
  .atlas-layout .research-header .page-nav { gap:24px; }
  .atlas-layout .research-header .header-inner { gap:24px; }
}
@media(max-width:800px) {
  .atlas-layout .research-header:has(.navigation-toggle[aria-expanded=true]) {
    --nav-ink:#26382e;
    --nav-muted:#626f61;
    --nav-rule:#bdc6b6;
    background:var(--paper);
  }
  .navigation-toggle { display:flex; align-items:center; align-self:center; min-height:44px; gap:22px; padding:0; color:var(--nav-ink); font:12px/1.2 var(--sans); }
  .navigation-icon { position:relative; width:19px; height:16px; }
  .navigation-icon::before,.navigation-icon::after { content:""; position:absolute; left:0; width:19px; height:1px; background:currentColor; transition:transform .18s; }
  .navigation-icon::before { top:5px; }
  .navigation-icon::after { top:11px; }
  .navigation-toggle[aria-expanded=true] .navigation-icon::before { transform:translateY(3px) rotate(45deg); }
  .navigation-toggle[aria-expanded=true] .navigation-icon::after { transform:translateY(-3px) rotate(-45deg); }
  .navigation-panel {
    position:absolute;
    inset:100% 0 auto;
    display:flex;
    flex-direction:column;
    gap:24px;
    margin:0;
    padding:16px 24px 24px;
    max-height:calc(100dvh - var(--section-nav-height,76px));
    overflow-y:auto;
    overscroll-behavior:contain;
    background:var(--paper);
    color:var(--ink);
    border-bottom:1px solid var(--rule-dark);
    box-shadow:0 16px 22px -22px #10241f99;
  }
  .navigation-toggle[aria-expanded=false] + .navigation-panel { display:none; }
  .atlas-layout .research-header .page-nav { display:flex; flex-direction:column; width:100%; gap:0; }
  .atlas-layout .research-header .page-nav a { align-self:stretch; min-height:58px; padding:12px 0; font:24px/1.2 "Newsreader Display",var(--serif); letter-spacing:-.25px; border-bottom:1px solid var(--rule); color:#687565; }
  .atlas-layout .research-header .page-nav a[aria-current] { color:var(--ink); }
  .atlas-layout .research-header .page-nav a::after { inset:50% 2px auto auto; width:15px; transform:scaleX(.4); }
  .publication-links { justify-content:flex-start; gap:32px; padding-top:2px; }
  .publication-links a { font-size:13px; }

}
@media(max-width:600px) {
  .atlas-layout .research-header .header-inner { min-height:67px; gap:16px; }
  .navigation-panel { padding:12px 16px 22px; }
  .navigation-toggle { gap:17px; }
}
/* Section destinations receive focus only to continue keyboard reading order;
   the active masthead link identifies the destination, while controls retain rings. */
:is(#leaderboard,#explore,#design,#about)[tabindex="-1"]:focus { outline:none; }

/* Only hero text passes beneath a transparent masthead; reading surfaces keep
   their ordinary layout and the header becomes opaque before they arrive. */
.atlas-layout .publication-header { clip-path:inset(var(--nav-cover,0px) 0 0); }