* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  -webkit-user-select: none;
  user-select: none;
  -webkit-touch-callout: none;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  overscroll-behavior: none;
  touch-action: manipulation;
  background: #ffffff;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

#board-wrap {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  touch-action: none;
}

#board {
  display: block;
  touch-action: none;
}

.banner {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: calc(env(safe-area-inset-top, 0px) + 14px) 16px 14px;
  background: rgba(20, 20, 20, 0.92);
  color: #ffffff;
  font-size: 20px;
  font-weight: 600;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.25);
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.banner.hidden {
  transform: translateY(-100%);
  opacity: 0;
  pointer-events: none;
}

#new-game-btn {
  appearance: none;
  border: none;
  border-radius: 8px;
  padding: 8px 16px;
  font-size: 16px;
  font-weight: 600;
  background: #ffffff;
  color: #111111;
  touch-action: manipulation;
}

#new-game-btn:active {
  background: #dddddd;
}