/* ============================================================
   BLU3 — shared site navigation
   ------------------------------------------------------------
   One canonical nav for every page. Self-contained: relies only
   on the shared --font-* tokens (styles/tokens.css) + literal
   brand colours, so it renders identically under both the home
   (rv9-) and subpage (rv-) systems. Link this LAST in each page
   so it wins style ties against either system's link reset.

   Markup contract:
     <header class="rv-nav" id="top">
       <div class="[page-wrap] rv-nav__inner">
         <a class="rv-nav__logo"><img></a>
         <nav class="rv-nav__links"> … </nav>
         <div class="rv-nav__right">
           <a class="rv-nav__book"> … </a>   (or a page CTA)
           <button class="rv-nav__burger"><span×3></button>
         </div>
       </div>
       <nav class="rv-nav__panel"> … </nav>
     </header>
   ============================================================ */
.rv-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,0.92);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid rgba(10,10,11,0.06);
}
.rv-nav__inner {
  height: 64px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 24px;
}
.rv-nav__logo img { height: 20px; width: auto; }

.rv-nav__links {
  justify-self: center;
  display: flex;
  align-items: center;
  gap: 36px;
}
.rv-nav__links a {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 14px;
  letter-spacing: 0.01em;
  color: #0A0A0B;
  position: relative;
  padding: 8px 0;
  transition: color 240ms ease;
}
.rv-nav__links a:hover,
.rv-nav__links a.on { color: #4169E1; }

.rv-nav__right {
  justify-self: end;
  display: flex;
  align-items: center;
  gap: 18px;
  font-family: var(--font-display);
  font-size: 13px;
  letter-spacing: 0.04em;
}
.rv-nav__book {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #0A0A0B;
  border: 0;
  border-bottom: 1px solid #0A0A0B;
  padding: 0 0 2px;
  background: none;
  font-family: var(--font-display);
  font-size: 13px;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: color 240ms ease, border-color 240ms ease;
}
.rv-nav__book:hover { color: #4169E1; border-bottom-color: #4169E1; }
.rv-nav__book .arr { font-family: var(--font-mono); transition: transform 240ms ease; }

/* Contact dropdown */
.rv-nav__contact { position: relative; display: inline-flex; }
.rv-nav__contact.is-open .rv-nav__book { color: #4169E1; border-bottom-color: #4169E1; }
.rv-nav__contact.is-open .rv-nav__book .arr { transform: rotate(180deg); }
.rv-nav__menu {
  position: absolute;
  top: calc(100% + 12px);
  right: 0;
  min-width: 252px;
  background: #FFFFFF;
  border: 1px solid rgba(10,10,11,0.09);
  border-radius: 7px;
  box-shadow: 0 22px 54px -26px rgba(10,10,11,0.42), 0 2px 8px -4px rgba(10,10,11,0.12);
  padding: 5px;
  display: none;
  flex-direction: column;
  z-index: 60;
}
.rv-nav__contact.is-open .rv-nav__menu { display: flex; animation: rv-nav-menu-in .18s ease; }
@keyframes rv-nav-menu-in { from { opacity: 0; transform: translateY(-6px); } to { opacity: 1; transform: none; } }
.rv-nav__menu-item {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 1px 12px;
  padding: 9px 13px;
  border-radius: 5px;
  font-family: var(--font-display);
  color: #0A0A0B;
  white-space: nowrap;
  transition: background 180ms ease;
}
.rv-nav__menu-item .lbl {
  grid-column: 1;
  font-weight: 400;
  font-size: 14px;
  letter-spacing: 0.005em;
  color: #0A0A0B;
  transition: color 180ms ease;
}
.rv-nav__menu-item .meta {
  grid-column: 1;
  font-weight: 400;
  font-size: 11.5px;
  letter-spacing: 0.008em;
  color: rgba(10,10,11,0.4);
  transition: color 180ms ease;
}
.rv-nav__menu-item .ext {
  grid-column: 2;
  grid-row: 1 / span 2;
  align-self: center;
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(10,10,11,0.28);
  transition: color 180ms ease, transform 180ms ease;
}
.rv-nav__menu-item:hover { background: rgba(65,105,225,0.06); }
.rv-nav__menu-item:hover .lbl { color: #4169E1; }
.rv-nav__menu-item:hover .meta { color: rgba(65,105,225,0.62); }
.rv-nav__menu-item:hover .ext { color: #4169E1; transform: translate(1px,-1px); }

.rv-nav__burger { display: none; }
.rv-nav__panel  { display: none; }

/* Nav collapses to burger at 880 — aligned with the content grids
   (heroes, section heads, founder/engage grids) so there's no band
   where a desktop nav sits over single-column content. */
@media (max-width: 880px) {
  .rv-nav__links { display: none; }
  .rv-nav__book  { display: none; }
  .rv-nav__contact { display: none; }
  .rv-nav__inner { grid-template-columns: auto 1fr auto; height: 58px; }

  .rv-nav__burger {
    display: flex; flex-direction: column; justify-content: center; gap: 5px;
    width: 44px; height: 44px; padding: 0 11px; margin-right: -11px;
    background: none; border: 0; cursor: pointer; justify-self: end;
  }
  .rv-nav__burger span {
    display: block; width: 22px; height: 1.5px; background: #0A0A0B;
    transition: transform .28s ease, opacity .2s ease;
  }
  .rv-nav.is-nav-open .rv-nav__burger span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
  .rv-nav.is-nav-open .rv-nav__burger span:nth-child(2) { opacity: 0; }
  .rv-nav.is-nav-open .rv-nav__burger span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

  .rv-nav__panel {
    display: block; overflow: hidden; max-height: 0;
    background: #FFFFFF;
    transition: max-height .4s cubic-bezier(.4,0,.2,1);
  }
  .rv-nav.is-nav-open .rv-nav__panel {
    max-height: 280px;
    border-top: 1px solid rgba(10,10,11,0.10);
    border-bottom: 1px solid rgba(10,10,11,0.12);
  }
  .rv-nav__panel a {
    display: flex; align-items: center; justify-content: space-between;
    padding: 20px clamp(20px,6vw,40px);
    font-family: var(--font-display); font-weight: 400; font-size: 22px;
    letter-spacing: -0.01em; color: #0A0A0B;
    border-top: 1px solid rgba(10,10,11,0.07);
    transition: color .2s ease;
  }
  .rv-nav__panel a:first-child { border-top: 0; }
  .rv-nav__panel a::after {
    content: "\2192"; font-family: var(--font-mono, monospace); font-size: 15px;
    color: #4169E1; opacity: 0; transform: translateX(-6px);
    transition: opacity .2s ease, transform .2s ease;
  }
  .rv-nav__panel a:hover, .rv-nav__panel a:active, .rv-nav__panel a.on { color: #4169E1; }
  .rv-nav__panel a:hover::after { opacity: 1; transform: translateX(0); }
}