html, body {
  height: 100%;
  margin: 0;
  padding: 0;
}

body {
  text-align: center;
  background-color: #011F3F;
  display: flex;
  flex-direction: column;
  justify-content: center; /* vertical center */
  align-items: center;     /* horizontal center */
}

#level-title {
  font-family: 'Press Start 2P', cursive;
  font-size: 2.2rem; /* slightly smaller to fit */
  margin-bottom: 60px;
  color: #FEF2BF;
}

.container {
  display: flex;
  flex-direction: column;
  gap: 10px; /* space between rows */
}

.row {
  display: flex;
  gap: 10px; /* space between buttons */
}

.btn {
  height: 130px; /* slightly smaller buttons */
  width: 130px;
  border: 10px solid black;
  border-radius: 20%;
}

.game-over {
  background-color: red;
  opacity: 0.8;
}

.red { background-color: red; }
.green { background-color: green; }
.blue { background-color: blue; }
.yellow { background-color: yellow; }

.pressed {
  box-shadow: 0 0 20px white;
  background-color: grey;
}