body {
  text-align: center;
}

.yellow {
  background-color: yellow;
  border: 5px solid black;
  height: 150px;
  width: 150px;
  border-radius: 20%;
  margin: 1rem;

}

.red {
  background-color: lightpink;
  border: 5px solid black;
  height: 150px;
  width: 150px;
  border-radius: 20%;
  margin: 1rem;

}

.purple {
  background-color: darkmagenta;
  border: 5px solid black;
  height: 150px;
  width: 150px;
  border-radius: 20%;
  margin: 1rem;

}

.green {
  background-color: orange;
  border: 5px solid black;
  height: 150px;
  width: 150px;
  border-radius: 20%;
  margin: 1rem;

}

.btn-container {
  display: flex;
  justify-content: center;
}

.gameflash {
  background-color: white;
}

.userflash {
  background-color: green;
}

body.dark-mode {
  background-color: #121212;
  color: #f1f1f1;
}

body.dark-mode h1,
body.dark-mode h2 {
  color: #f1f1f1;
}

body.dark-mode .yellow,
body.dark-mode .red,
body.dark-mode .purple,
body.dark-mode .green {
  border-color: #333;
}

body,
h1,
h2,
.yellow,
.red,
.purple,
.green {
  transition: all 0.3s ease;
}

#dark-toggle {
  position: absolute;
  top: 10px;
  right: 10px;
  padding: 6px 12px;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  background: #eee;
  color: #121212;
  transition: all 0.3s ease;
}

#dark-toggle:hover {
  background: #ddd;
}

body.dark-mode #dark-toggle {
  background: #333;
  color: #f1f1f1;
}

body.dark-mode #dark-toggle:hover {
  background: #555;
}