/* Shared sticky chrome for the concept demonstration site. */
.site-nav {
  --nav-h: 46px;
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  right: 0;
  min-height: var(--nav-h);
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px 10px;
  padding: 6px 12px;
  padding-left: max(12px, env(safe-area-inset-left, 0px));
  padding-right: max(12px, env(safe-area-inset-right, 0px));
  background: rgba(8, 14, 26, 0.94);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  font-family: "Segoe UI", system-ui, sans-serif;
  color: #f4f7fb;
  box-sizing: border-box;
}
.site-nav *, .site-nav *::before, .site-nav *::after { box-sizing: border-box; }
.site-nav a {
  color: inherit;
  text-decoration: none;
  -webkit-tap-highlight-color: transparent;
}
.site-nav__brand {
  flex: 0 0 auto;
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: #f4f7fb;
  white-space: nowrap;
}
.site-nav__brand span { color: #3ec6ff; font-weight: 650; }
.site-nav__brand .site-nav__brand-short { display: none; }
.site-nav__row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1 1 auto;
  min-width: 0;
}
.site-nav__concepts,
.site-nav__modes {
  display: flex;
  align-items: center;
  gap: 4px;
  min-width: 0;
}
.site-nav__concepts {
  flex: 1 1 auto;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}
.site-nav__concepts::-webkit-scrollbar { display: none; }
.site-nav__modes { flex: 0 0 auto; }
.site-nav__pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 30px;
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 650;
  color: #a9b4c7;
  border: 1px solid transparent;
  white-space: nowrap;
}
.site-nav__pill:hover {
  color: #3ec6ff;
  border-color: rgba(62, 198, 255, 0.28);
  background: rgba(62, 198, 255, 0.08);
}
.site-nav__pill.is-current {
  color: #fff;
  background: rgba(62, 198, 255, 0.22);
  border-color: rgba(62, 198, 255, 0.45);
  pointer-events: none;
}
.site-nav__modes .site-nav__pill.is-current {
  background: rgba(62, 198, 255, 0.32);
}
.site-nav__modes[hidden] { display: none !important; }

/* Narrow phones: two-row chrome so Look|Inspect never get clipped. */
@media (max-width: 640px) {
  .site-nav {
    --nav-h: 84px;
    align-items: stretch;
    gap: 6px;
    padding: 8px;
    padding-left: max(8px, env(safe-area-inset-left, 0px));
    padding-right: max(8px, env(safe-area-inset-right, 0px));
  }
  .site-nav__brand { font-size: 0.72rem; }
  .site-nav__brand .site-nav__brand-full { display: none; }
  .site-nav__brand .site-nav__brand-short { display: inline; }
  .site-nav__row {
    display: flex;
    align-items: center;
    gap: 6px;
    width: 100%;
    min-width: 0;
  }
  .site-nav__modes {
    margin-left: 0;
    width: 100%;
    display: grid;
    /* 3 (slim) or 4 (eth Look|Inspect|Eval|Still) equal pills */
    grid-template-columns: repeat(auto-fit, minmax(0, 1fr));
    gap: 6px;
  }
  .site-nav__modes .site-nav__pill {
    width: 100%;
    min-height: 34px;
    font-size: 0.8rem;
  }
  .site-nav__pill { min-height: 28px; padding: 3px 9px; font-size: 0.72rem; }
}

body.has-site-nav {
  --site-nav-h: 46px;
}
@media (max-width: 640px) {
  body.has-site-nav { --site-nav-h: 84px; }
}
body.has-site-nav .hud {
  top: calc(12px + var(--site-nav-h) + env(safe-area-inset-top, 0px));
}
body.has-site-nav #btnPanel {
  top: calc(12px + var(--site-nav-h) + env(safe-area-inset-top, 0px));
}
@media (max-width: 720px) {
  body.has-site-nav .hud { top: auto; }
  body.has-site-nav #btnPanel { top: auto; }
}

/* First-load pulse so mobile users find Controls when the panel starts closed. */
@keyframes site-nav-pulse {
  0%, 100% { box-shadow: 0 8px 28px rgba(0,0,0,.4); }
  50% { box-shadow: 0 0 0 4px rgba(62,198,255,.35), 0 8px 28px rgba(0,0,0,.4); }
}
body.panel-closed #btnPanel.pulse-once {
  animation: site-nav-pulse 1.1s ease-in-out 2;
}