/* Bio2Twin shell v2 + HOME_TOPBAR_MEGA_MENU_V1 */
:root{
  --bt-bg:#07100e;
  --bt-panel:#0d1b16;
  --bt-ink:#f3f4ef;
  --bt-muted:#a7afa7;
  --bt-line:rgba(185,255,203,.08);
  --bt-mint:#b9ffcb;
  --bt-max:1180px;
  --bt-nav-h:76px;
  --bt-mega-h:310px;
  --bt-mega-bg:#0a1411;
  --bt-mega-ink:#f3f4ef;
  --bt-mega-muted:rgba(243,244,239,.48);
  --bt-mega-line:rgba(185,255,203,.08);
}
*{box-sizing:border-box}
body{overflow-x:hidden}

.bt-header{
  position:sticky;top:0;z-index:80;
  background:rgba(7,16,14,.96);
  border-bottom:1px solid rgba(255,255,255,.10);
  color:var(--bt-ink);
  overflow:visible;
}
.bt-header-inner{
  width:min(calc(100% - 76px),var(--bt-max));
  min-height:var(--bt-nav-h);
  margin:0 auto;
  display:grid;
  grid-template-columns:auto 1fr auto;
  align-items:center;
  gap:24px;
  position:relative;
  z-index:83;
}
.bt-brand{display:flex;align-items:center;gap:16px;line-height:0;flex:0 0 auto;text-decoration:none;color:var(--bt-ink)}
.bt-brand-wordmark{display:block;height:21px;width:auto;max-width:178px;object-fit:contain;flex:0 0 auto}
.bt-brand-mark{width:42px;height:42px;display:block;object-fit:contain;flex:0 0 42px;filter:drop-shadow(0 0 9px rgba(22,220,255,.24))}

.bt-nav{
  display:flex;align-items:center;justify-content:center;gap:4px;
  white-space:nowrap;
}
.bt-nav__trigger{
  appearance:none;border:0;background:transparent;cursor:pointer;
  min-height:40px;padding:0 12px;border-radius:10px;
  font:inherit;font-size:13px;font-weight:560;color:#c4cbc4;
}
.bt-nav__trigger:hover,
.bt-nav__trigger[aria-expanded="true"],
.bt-nav__trigger:focus-visible{
  color:var(--bt-ink);background:rgba(255,255,255,.06);
}
.bt-nav__link{
  display:inline-flex;align-items:center;min-height:40px;padding:0 12px;
  border-radius:10px;text-decoration:none;font-size:13px;font-weight:560;color:#c4cbc4;
}
.bt-nav__link:hover,
.bt-nav__link[aria-current="page"],
.bt-nav__link:focus-visible{color:var(--bt-ink);background:rgba(255,255,255,.06)}
.bt-nav__trigger:focus-visible,
.bt-nav__link:focus-visible{outline:2px solid rgba(185,255,203,.45);outline-offset:2px}

.bt-header__cta{display:flex;align-items:center;gap:10px;justify-self:end}
.bt-dayone,.bt-cta-secondary,.bt-cta-primary{
  display:inline-flex;align-items:center;justify-content:center;
  min-height:38px;padding:0 14px;border-radius:999px;
  text-decoration:none;font-size:12px;font-weight:700;
}
.bt-dayone,.bt-cta-primary{
  border:1px solid var(--bt-mint);background:var(--bt-mint);color:#07100e;
}
.bt-cta-secondary{
  border:1px solid rgba(180,220,195,.28);background:transparent;color:var(--bt-ink);font-weight:560;
}
.bt-cta-secondary:hover{border-color:rgba(180,220,195,.45);color:var(--bt-mint)}
.bt-dayone:hover,.bt-cta-primary:hover{filter:brightness(1.04)}

.bt-account{display:none} /* account lives in Resources / drawer */
.bt-menu{
  display:none;width:38px;height:38px;border:1px solid var(--bt-line);
  border-radius:999px;background:#0b1612;color:var(--bt-ink);cursor:pointer;
}
.bt-mobile-day1{display:none}

/* Mega panels */
.bt-mega{
  position:absolute;left:0;right:0;top:100%;
  height:var(--bt-mega-h);
  background:var(--bt-mega-bg);
  border-bottom:1px solid var(--bt-mega-line);
  color:var(--bt-mega-ink);
  opacity:0;transform:translateY(-8px);pointer-events:none;visibility:hidden;
  transition:opacity .2s ease, transform .2s ease;
  z-index:81;
}
.bt-mega.is-open{
  opacity:1;transform:translateY(0);pointer-events:auto;visibility:visible;
}
.bt-mega__inner{
  width:min(calc(100% - 40px),var(--bt-max));
  margin:0 auto;height:100%;
  display:grid;grid-template-columns:minmax(0,1.05fr) minmax(280px,.95fr);
  gap:22px;padding:18px 0 20px;
}
.bt-mega__cols{display:grid;gap:12px 18px;align-content:start}
.bt-mega__cols--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.bt-mega__cols--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.bt-mega__label{
  margin:0 0 8px;font-size:11px;font-weight:600;color:var(--bt-mega-muted);
}
.bt-mega__list{list-style:none;margin:0;padding:0;display:grid;gap:2px}
.bt-mega__link{
  display:flex;align-items:center;justify-content:space-between;gap:10px;
  min-height:30px;padding:3px 7px;margin:0 -7px;border-radius:8px;
  text-decoration:none;color:rgba(243,244,239,.82);
  font-size:15px;line-height:1.35;font-weight:520;letter-spacing:-.015em;
}
.bt-mega__link span{flex:1}
.bt-mega__link i{
  font-style:normal;opacity:0;transform:translateX(-4px);
  transition:opacity .18s ease, transform .18s ease;
  color:rgba(185,255,203,.72);font-size:13px;
}
.bt-mega__link:hover,
.bt-mega__link:focus-visible,
.bt-mega__link.is-active{
  color:var(--bt-mega-ink);background:rgba(255,255,255,.055);
}
.bt-mega__link:hover i,
.bt-mega__link:focus-visible i,
.bt-mega__link.is-active i{opacity:1;transform:translateX(0)}
.bt-mega__link:focus-visible{outline:2px solid rgba(185,255,203,.42);outline-offset:2px}

.bt-mega__visual{
  position:relative;border-radius:16px;overflow:hidden;
  background:#111;min-height:220px;align-self:stretch;
}
.bt-mega__img,.bt-mega__img-b{
  position:absolute;inset:0;width:100%;height:100%;
  object-fit:cover;object-position:center 30%;
  transition:opacity .26s ease;
}
.bt-mega__img-b{opacity:0}
.bt-mega__visual.is-swap .bt-mega__img{opacity:0}
.bt-mega__visual.is-swap .bt-mega__img-b{opacity:1}
.bt-mega__shade{
  position:absolute;left:0;right:0;bottom:0;height:48%;
  background:linear-gradient(180deg,transparent,rgba(8,10,9,.78));
  pointer-events:none;
}
.bt-mega__caption{
  position:absolute;left:18px;right:18px;bottom:18px;z-index:1;color:#f5f3ee;
}
.bt-mega__caption strong{display:block;font-size:16px;letter-spacing:-.02em;font-weight:650}
.bt-mega__caption p{margin:5px 0 0;font-size:12px;line-height:1.45;color:rgba(245,243,238,.78);min-height:2.4em}

.bt-mega-backdrop{
  display:none;position:fixed;left:0;right:0;top:var(--bt-nav-h);bottom:0;z-index:70;background:transparent;
}
.bt-mega-backdrop.is-open{display:block}

/* Mobile drawer */
.bt-drawer{display:none}
.bt-drawer.open{
  display:block;position:fixed;inset:0;z-index:90;
  background:#07100e;color:var(--bt-ink);
  padding:calc(var(--bt-nav-h) + 8px) 18px 120px;overflow:auto;
}
.bt-drawer__group{border-bottom:1px solid rgba(255,255,255,.1)}
.bt-drawer__summary{
  list-style:none;cursor:pointer;display:flex;align-items:center;justify-content:space-between;
  min-height:52px;font-size:16px;font-weight:650;color:var(--bt-ink);
}
.bt-drawer__summary::-webkit-details-marker{display:none}
.bt-drawer__links{display:grid;gap:2px;padding:0 0 14px}
.bt-drawer__links a{
  display:block;padding:12px 4px;text-decoration:none;color:#c4cbc4;font-size:15px;
}
.bt-drawer__links a:hover{color:var(--bt-mint)}
.bt-drawer__foot{
  position:fixed;left:0;right:0;bottom:0;z-index:91;
  display:grid;grid-template-columns:1fr 1fr;gap:10px;
  padding:14px 18px calc(14px + env(safe-area-inset-bottom));
  background:#07100e;border-top:1px solid rgba(255,255,255,.1);
}
.bt-drawer__account{padding:16px 4px;display:grid;gap:8px}
.bt-drawer__account a,.bt-drawer__account .bt-member-id{color:#c4cbc4;text-decoration:none;font-size:13px}
.bt-header :focus-visible{outline:2px solid var(--bt-mint);outline-offset:3px}

@media(max-width:1140px){
  .bt-nav,.bt-header__cta,.bt-mega,.bt-mega-backdrop{display:none!important}
  .bt-header-inner{
    grid-template-columns:auto 1fr auto auto;
    width:min(calc(100% - 28px),var(--bt-max));
    min-height:68px;gap:12px;
  }
  .bt-mobile-day1{
    display:inline-flex;align-items:center;justify-content:center;
    min-height:36px;padding:0 12px;border-radius:999px;
    background:var(--bt-mint);color:#07100e;text-decoration:none;
    font-size:12px;font-weight:700;justify-self:end;
  }
  .bt-menu{display:inline-flex;align-items:center;justify-content:center}
  body.bt-drawer-open{overflow:hidden}
  .bt-brand{gap:12px}
  .bt-brand-wordmark{height:17px;max-width:138px}
  .bt-brand-mark{width:34px;height:34px;flex-basis:34px}
}
@media(prefers-reduced-motion:reduce){
  .bt-mega,.bt-mega__img,.bt-mega__img-b,.bt-mega__link i{transition:none!important}
}

/* homepage scroll targets */
#baseline,#body-state,#truth-loop,#model-cycle,#research-intelligence,#model-declaration{
  scroll-margin-top:96px;
}

/* Biology mega menu: Sovereign OI blue, shared across Bio2Twin */
#bt-mega-biology{
  background:linear-gradient(180deg,#081923 0%,#0b2430 100%);
  color:#eaf8f8;
  border-top:1px solid rgba(140,220,230,.10);
  border-bottom:1px solid rgba(140,220,230,.18);
}
#bt-mega-biology .bt-mega__list{gap:0;}
#bt-mega-biology .bt-mega__label{
  color:#a2bec9;
  font-size:11px;
  font-weight:400;
  line-height:1.35;
  margin:0 0 8px;
}
#bt-mega-biology .bt-mega__link{
  color:#eaf8f8;
  font-size:14px;
  font-weight:400;
  line-height:1.4;
  letter-spacing:0;
  min-height:34px;
  padding:5px 8px;
  white-space:normal;
}
#bt-mega-biology .bt-mega__link:hover,
#bt-mega-biology .bt-mega__link:focus-visible,
#bt-mega-biology .bt-mega__link.is-active{
  background:rgba(124,212,212,.10);
  color:#9ee7d7;
}
#bt-mega-biology .bt-mega__link:focus-visible{
  outline:2px solid #9ee7d7;
  outline-offset:2px;
}
#bt-mega-biology .bt-mega__link i{color:#9ee7d7;}
#bt-mega-biology .bt-mega__visual{
  background:#081923;
  border:1px solid rgba(140,220,230,.16);
  box-shadow:0 10px 30px rgba(0,0,0,.22);
}

/* Compact bilingual N-of-1 topbar label */
.bt-nav__link--n1{display:flex!important;flex-direction:column;align-items:flex-start;justify-content:center;gap:1px;line-height:1.05!important;white-space:nowrap}
.bt-nav__link--n1>span{display:block;font-size:12px;letter-spacing:.01em}
.bt-nav__link--n1>small{display:block;font-size:9px;line-height:1.1;color:inherit;opacity:.7;letter-spacing:.02em;font-weight:500}
@media(max-width:1240px){.bt-nav__link--n1>span{font-size:11px}.bt-nav__link--n1>small{font-size:8px}}