/* Session presentation is independent from the browser's native fullscreen API. */
.site-header,
.sidebar-panel,
.site-footer,
.arena-bottom-bar {
  transition:
    transform 320ms cubic-bezier(0.4, 0, 0.2, 1),
    opacity 220ms ease;
}

.session-toolbar {
  position: absolute;
  top: 1rem;
  right: 1rem;
  z-index: 30;
  display: none;
  align-items: center;
  gap: 0.6rem;
}

.btn-danger {
  color: #fff;
  background: color-mix(in srgb, var(--accent-red) 82%, transparent);
  border-color: color-mix(in srgb, var(--accent-red) 72%, white);
  backdrop-filter: blur(10px);
}

.btn-danger:hover {
  background: var(--accent-red);
}

.session-toolbar kbd {
  margin-left: 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  opacity: 0.8;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) {
  overflow: hidden;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .canvas-container {
  position: fixed;
  inset: 0;
  z-index: 100;
  width: 100dvw;
  height: 100dvh;
  min-height: 0;
  max-height: none;
  border: 0;
  border-radius: 0;
  box-shadow: none;
  animation: session-stage-enter 220ms ease-out both;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .session-toolbar {
  display: flex;
}

body[data-game-state="playing"] .arena-canvas {
  cursor: none;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .live-hud {
  position: fixed;
  z-index: 140;
  top: 0.65rem;
  left: 0.65rem;
  right: auto;
  grid-template-columns: repeat(6, max-content);
  gap: 0.3rem;
  max-width: calc(100dvw - 1.3rem);
  pointer-events: none;
  animation: session-hud-enter 300ms 100ms ease-out both;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .hud-pill {
  gap: 0.05rem;
  min-width: 0;
  padding: 0.34rem 0.58rem;
  background: color-mix(in srgb, var(--bg-surface) 72%, transparent);
  border: 0;
  border-radius: var(--radius-sm);
  box-shadow: none;
  backdrop-filter: blur(10px);
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .hud-label {
  color: var(--text-muted);
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  opacity: 1;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .hud-value {
  font-size: 0.96rem;
  line-height: 1.2;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .site-header {
  position: relative;
  z-index: 130;
  transform: translateY(calc(-100% - 2rem));
  opacity: 0;
  pointer-events: none;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .sidebar-panel {
  position: relative;
  z-index: 130;
  transform: translateX(calc(-100% - 2rem));
  opacity: 0;
  pointer-events: none;
}

body:is([data-game-state="countdown"], [data-game-state="playing"]) .site-footer,
body:is([data-game-state="countdown"], [data-game-state="playing"]) .arena-bottom-bar {
  position: relative;
  z-index: 130;
  transform: translateY(calc(100% + 2rem));
  opacity: 0;
  pointer-events: none;
}

/* Native fullscreen changes the browser chrome, not the session layout. */
:fullscreen,
:-webkit-full-screen {
  background: var(--bg-main);
}

:fullscreen .app-layout,
:-webkit-full-screen .app-layout {
  max-width: none;
}

@keyframes session-stage-enter {
  from { opacity: 0.6; transform: scale(0.99); }
  to { opacity: 1; transform: scale(1); }
}

@keyframes session-hud-enter {
  from { opacity: 0; transform: translateY(-12px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 760px) {
  body:is([data-game-state="countdown"], [data-game-state="playing"]) .live-hud {
    right: auto;
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .session-toolbar {
    inset: auto 0.75rem 0.75rem auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  .site-header,
  .sidebar-panel,
  .site-footer,
  .arena-bottom-bar,
  body:is([data-game-state="countdown"], [data-game-state="playing"]) .canvas-container,
  body:is([data-game-state="countdown"], [data-game-state="playing"]) .live-hud {
    animation: none;
    transition-duration: 1ms;
  }
}