html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(1200px 700px at 50% 0%, #eaf5ff 0%, #d7ecff 35%, #cfe6ff 70%, #c3ddff 100%);
  font-family: 'Poppins', system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  color: #123;
}
#game-container {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: 16px;
  box-sizing: border-box;
}
canvas {
  box-shadow: 0 24px 70px rgba(15, 28, 45, 0.28);
  border-radius: 18px;
  border: 1px solid rgba(255,255,255,0.45);
  touch-action: none;
  -ms-touch-action: none;
}

#game-container:fullscreen {
  padding: 0;
  width: 100vw;
  height: 100vh;
  background: #000;
}
#game-container:fullscreen canvas {
  width: 100vw;
  height: 100vh;
  object-fit: cover;
  border-radius: 0;
  box-shadow: none;
  border: 0;
}
#game-container:-webkit-full-screen {
  padding: 0;
  width: 100vw;
  height: 100vh;
  background: #000;
}
#game-container:-webkit-full-screen canvas {
  width: 100vw;
  height: 100vh;
  object-fit: cover;
  border-radius: 0;
  box-shadow: none;
  border: 0;
}
#game-container:-moz-full-screen {
  padding: 0;
  width: 100vw;
  height: 100vh;
  background: #000;
}
#game-container:-moz-full-screen canvas {
  width: 100vw;
  height: 100vh;
  object-fit: cover;
  border-radius: 0;
  box-shadow: none;
  border: 0;
}
.overlay-input {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  background: rgba(255,255,255,0.85);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  padding: 18px 20px;
  border-radius: 8px;
  box-shadow: 0 12px 36px rgba(0,0,0,0.2);
}
.overlay-input input {
  padding: 10px 12px;
  font-size: 15px;
  border: 1px solid #d0d7de;
  border-radius: 6px;
}
.overlay-input button {
  padding: 10px 14px;
  margin-left: 8px;
  font-size: 15px;
  cursor: pointer;
  border: 0;
  border-radius: 6px;
  background: #4dabf7;
  color: #fff;
}

@media (max-width: 768px), (hover: none) and (pointer: coarse) {
  html, body {
    background: #000;
    height: 100%;
    width: 100%;
  }
  #game-container {
    padding: 0;
    width: 100vw;
    height: 100dvh;
  }
  canvas {
    border-radius: 0;
    box-shadow: none;
    border: 0;
  }
}