:root {
  --bg-color: #1a1a1a;
  --text-color: #ffffff;
  --red: #ff4d4d;
  --green: #2ecc71;
  --blue: #3498db;
  --yellow: #f1c40f;
  --btn-size: 150px;
}

body {
  text-align: center;
  background-color: var(--bg-color);
  color: var(--text-color);
  font-family: "Press Start 2P", cursive;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  margin: 0;
  transition: background-color 0.2s ease;
}

h1 {
  font-size: 3rem;
  margin-bottom: 0.5rem;
  text-shadow: 2px 2px 0px #000;
}

h2 {
  font-size: 1.2rem;
  margin-bottom: 2rem;
  font-weight: normal;
  color: #ccc;
}

.btn-container {
  display: flex;
  flex-direction: column;
  gap: 15px;
  background: #2c3e50;
  padding: 30px;
  border-radius: 50%;
  border: 10px solid #34495e;
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.5);
}

.line-one,
.line-two {
  display: flex;
  gap: 15px;
}

.btn {
  height: var(--btn-size);
  width: var(--btn-size);
  border-radius: 25px;
  border: 4px solid rgba(0, 0, 0, 0.2);
  cursor: pointer;
  transition: all 0.1s ease;
  box-shadow: 0 6px 0 rgba(0, 0, 0, 0.3);
}

.btn:active {
  box-shadow: 0 2px 0 rgba(0, 0, 0, 0.3);
  transform: translateY(4px);
}

.red {
  background-color: var(--red);
  border-top-left-radius: 100%;
}

.green {
  background-color: var(--green);
  border-top-right-radius: 100%;
}

.yellow {
  background-color: var(--yellow);
  border-bottom-left-radius: 100%;
}

.blue {
  background-color: var(--blue);
  border-bottom-right-radius: 100%;
}

.flash {
  background-color: white;
  box-shadow: 0 0 20px white;
  transform: scale(0.98);
}

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

body.game-over {
  background-color: red;
}