*,
*::before,
*::after { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: #16303a;
  color: #f6efe4;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC", "Noto Sans SC", sans-serif;
  touch-action: none;
  user-select: none;
  -webkit-user-select: none;
  -webkit-tap-highlight-color: transparent;
}

#c {
  display: block;
  width: 100%;
  height: 100%;
}

#fail {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  margin: 0;
  padding: 24px;
  text-align: center;
  background: #16303a;
}

#fail[hidden] { display: none; }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

button {
  font: inherit;
  color: inherit;
  appearance: none;
  -webkit-appearance: none;
  border: 1px solid rgba(246, 228, 196, 0.38);
  background: rgba(28, 18, 12, 0.72);
  border-radius: 14px;
  padding: 6px 4px 7px;
  min-width: 0;
  min-height: 44px;
  line-height: 1.15;
  cursor: pointer;
}

button:focus { outline: none; }

button:focus-visible {
  outline: 2px solid #f0c27a;
  outline-offset: 2px;
}

button:active,
button.is-down {
  background: #e39a45;
  color: #2a160c;
  border-color: #f0c27a;
  transform: translateY(1px);
}

@media (hover: hover) and (pointer: fine) {
  button:hover { background: rgba(54, 34, 22, 0.88); }
  button:active:hover,
  button.is-down:hover { background: #e39a45; }
}

kbd {
  display: block;
  margin-bottom: 2px;
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 10px;
  font-weight: 560;
  letter-spacing: 0.04em;
  opacity: 0.72;
}

.top {
  position: fixed;
  z-index: 3;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 8px;
  padding: calc(8px + env(safe-area-inset-top)) 10px 0;
  pointer-events: none;
}

.top button { pointer-events: auto; }

.top-r { display: flex; gap: 8px; }

#btn-sound,
#btn-cam,
#btn-help {
  min-width: 52px;
  padding-inline: 10px;
  background: rgba(18, 16, 14, 0.46);
  font-size: 13px;
}

#hint {
  position: fixed;
  z-index: 2;
  left: 12px;
  right: 12px;
  bottom: calc(132px + env(safe-area-inset-bottom));
  margin: 0;
  text-align: center;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: #f8f1e6;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.55);
  pointer-events: none;
  transition: opacity 0.6s linear;
}

#hint.is-gone { opacity: 0; }

#help {
  position: fixed;
  z-index: 4;
  left: 10px;
  right: 10px;
  bottom: calc(128px + env(safe-area-inset-bottom));
  max-height: min(46vh, 320px);
  overflow: auto;
  margin: 0;
  padding: 12px 14px 8px;
  border-radius: 16px;
  background: rgba(22, 14, 10, 0.92);
  border: 1px solid rgba(246, 228, 196, 0.28);
  -webkit-overflow-scrolling: touch;
}

#help[hidden] { display: none; }

#help p {
  margin: 0 0 8px;
  font-size: 13px;
  line-height: 1.45;
}

.dock {
  position: fixed;
  z-index: 3;
  left: 0;
  right: 0;
  bottom: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
  padding: 8px 10px calc(10px + env(safe-area-inset-bottom));
}

.pad { font-size: 15px; }

.pad-main { min-height: 56px; }

.pad-go {
  background: rgba(92, 42, 18, 0.78);
  border-color: rgba(240, 176, 96, 0.7);
}

@media (max-width: 340px) {
  .pad { font-size: 14px; }
  .dock { gap: 6px; padding-inline: 8px; }
}

@media (max-height: 560px) {
  .pad { min-height: 40px; font-size: 13px; }
  .pad-main { min-height: 46px; }
  #hint { bottom: calc(112px + env(safe-area-inset-bottom)); }
  #help { bottom: calc(108px + env(safe-area-inset-bottom)); }
}

@media (prefers-reduced-motion: reduce) {
  #hint { transition: none; }
  button:active, button.is-down { transform: none; }
}