.app-screen {
  position: relative;
  display: none;
  grid-template-rows: auto 1fr auto;
  width: 100%;
  height: 100%;
  min-height: 0;
  overflow: hidden;
}

.app-screen.is-active { display: grid; }
.app-screen.active { display: grid; }
.app-screen.is-active:not(.active) { display: none; }

.stub-screen {
  align-self: center;
  justify-self: center;
  width: min(100%, 320px);
  padding: 28px 22px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 24px;
  background: linear-gradient(135deg, rgba(47, 210, 255, 0.08), rgba(243, 16, 186, 0.06));
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.05);
  text-align: center;
}

.stub-screen h2 { margin: 8px 0; font-size: clamp(28px, 8vw, 40px); letter-spacing: -0.04em; }
.stub-screen p { margin: 0; color: #aeb8cb; font-size: 14px; line-height: 1.5; }
.screen-kicker { color: #2fd2ff; font-size: 10px; font-weight: 900; letter-spacing: 0.16em; text-transform: uppercase; }

.bottom-navigation {
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: max(10px, env(safe-area-inset-bottom));
  z-index: 12;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  align-items: stretch;
  gap: 5px;
  padding: 6px;
  border: 1px solid rgba(255, 255, 255, 0.11);
  border-radius: 23px;
  background: linear-gradient(180deg, rgba(16, 22, 34, 0.94), rgba(6, 9, 16, 0.96));
  box-shadow: 0 18px 42px rgba(0, 0, 0, 0.44), inset 0 1px 0 rgba(255, 255, 255, 0.07);
  backdrop-filter: blur(18px) saturate(135%);
  -webkit-backdrop-filter: blur(18px) saturate(135%);
}

.splash-layer ~ .app-shell .bottom-navigation { visibility: hidden; pointer-events: none; }
.app-frame.splash-done .bottom-navigation { visibility: visible; pointer-events: auto; }

/* V1.9.3 — modern app-style navigation. */
.nav-button,
.nav-item,
.bottom-nav-item {
  appearance: none;
  -webkit-appearance: none;
  display: grid;
  justify-items: center;
  align-content: center;
  gap: 3px;
  min-width: 0;
  min-height: 52px;
  padding: 6px 4px;
  border: 1px solid transparent;
  border-radius: 17px;
  outline: 0;
  background: transparent;
  color: #8f9bb0;
  font: inherit;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  transition: background 160ms ease, border-color 160ms ease, color 160ms ease, transform 160ms ease;
}

.nav-button:hover,
.nav-item:hover,
.bottom-nav-item:hover { color: #edf5ff; background: rgba(255,255,255,.035); }

.nav-button:active,
.nav-item:active,
.bottom-nav-item:active { transform: scale(.95); }

.nav-button.active,
.nav-item.is-active,
.bottom-nav-item.active {
  background: linear-gradient(145deg, rgba(47,210,255,.18), rgba(61,61,234,.2));
  border-color: rgba(47,210,255,.22);
  color: #fff;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.07), 0 5px 18px rgba(0,0,0,.14);
}

.nav-icon,
.bottom-nav-icon {
  display: grid;
  place-items: center;
  width: 28px;
  height: 24px;
  font-size: 19px;
  line-height: 1;
  font-family: system-ui, -apple-system, "Segoe UI Symbol", sans-serif;
}

.nav-label,
.bottom-nav-label {
  display: block;
  max-width: 100%;
  overflow: hidden;
  color: inherit;
  font-size: 8px;
  font-weight: 900;
  letter-spacing: .065em;
  line-height: 1;
  text-overflow: ellipsis;
  text-transform: uppercase;
  white-space: nowrap;
}

.nav-button:focus-visible,
.nav-item:focus-visible,
.bottom-nav-item:focus-visible {
  outline: 2px solid #ff9df2;
  outline-offset: 2px;
}

#screen-home { padding-bottom: 84px; }

#screen-home .mascot-orbit { position: relative; z-index: 20; }
#screen-home .home-mascot-button {
  position: absolute;
  inset: 0;
  z-index: 21;
  display: block;
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
  border: 0;
  background: transparent;
  color: inherit;
  cursor: pointer;
  pointer-events: auto;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

#screen-home .home-mascot-button .mascot-ring,
#screen-home .home-mascot-button .mascot-badge,
#screen-home .home-mascot-button .mascot-caption,
#screen-home .home-mascot-button .home-mascot-image { pointer-events: none; }

#screen-home .home-mascot-button:focus-visible { outline: 3px solid #ff9df2; outline-offset: 3px; border-radius: 18px; }

@media (max-width: 360px) {
  .bottom-navigation { left: 8px; right: 8px; padding: 5px; border-radius: 20px; gap: 3px; }
  .nav-button, .nav-item, .bottom-nav-item { min-height: 50px; border-radius: 15px; padding-inline: 3px; }
  .nav-icon, .bottom-nav-icon { width: 25px; height: 22px; font-size: 18px; }
  .nav-label, .bottom-nav-label { font-size: 7px; }
  #screen-home { padding-bottom: 78px; }
}

@media (prefers-reduced-motion: reduce) {
  .nav-button, .nav-item, .bottom-nav-item { transition: none; }
}