body {
  font-family: sans-serif;
  background-color: #f0f0f0;
  color: #333;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  transition: background-color 0.3s, color 0.3s;
}

body.dark {
  background-color: #1a1a2e;
  color: #e0e0e0;
}

.container {
  text-align: center;
  background-color: white;
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
  transition: background-color 0.3s, box-shadow 0.3s;
}

body.dark .container {
  background-color: #16213e;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
}

h1 {
  color: #333;
  transition: color 0.3s;
}

body.dark h1 {
  color: #e0e0e0;
}

#theme-toggle {
  position: fixed;
  top: 1rem;
  right: 1rem;
  background: none;
  border: 2px solid #ccc;
  border-radius: 50%;
  width: 44px;
  height: 44px;
  font-size: 1.3rem;
  cursor: pointer;
  transition: border-color 0.3s, background-color 0.3s;
  display: flex;
  align-items: center;
  justify-content: center;
}

#theme-toggle:hover {
  background-color: rgba(0, 0, 0, 0.08);
}

body.dark #theme-toggle {
  border-color: #555;
}

body.dark #theme-toggle:hover {
  background-color: rgba(255, 255, 255, 0.1);
}

#generate-btn {
  background-color: #4CAF50;
  color: white;
  border: none;
  padding: 10px 20px;
  font-size: 1rem;
  cursor: pointer;
  border-radius: 5px;
  margin-bottom: 1rem;
}

#generate-btn:hover {
  background-color: #45a049;
}

#numbers-display {
  display: flex;
  justify-content: center;
  margin-top: 1rem;
}

.number {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: #f2f2f2;
  color: #333;
  font-size: 1.2rem;
  display: flex;
  justify-content: center;
  align-items: center;
  margin: 0 5px;
  transition: background-color 0.3s, color 0.3s;
}

body.dark .number {
  background-color: #0f3460;
  color: #e0e0e0;
}