:root {
  --bg-color: #f0f0f0;
  --text-color: #333;
  --button-bg: #4CAF50;
  --button-hover: #45a049;
}

body.dark-mode {
  --bg-color: #121212;
  --text-color: #e0e0e0;
  --button-bg: #388E3C;
  --button-hover: #2E7D32;
}

body {
  font-family: sans-serif;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100vh;
  margin: 0;
  background-color: var(--bg-color);
  color: var(--text-color);
  transition: background-color 0.3s, color 0.3s;
}

h1 {
  color: var(--text-color);
}

#theme-toggle {
  position: absolute;
  top: 20px;
  right: 20px;
  padding: 8px 16px;
  cursor: pointer;
  border-radius: 20px;
  border: 1px solid var(--text-color);
  background: transparent;
  color: var(--text-color);
  font-size: 0.9em;
  transition: all 0.3s;
}

#theme-toggle:hover {
  background: var(--text-color);
  color: var(--bg-color);
}

#generator {
  padding: 10px 20px;
  font-size: 1.2em;
  border-radius: 5px;
  cursor: pointer;
  background-color: var(--button-bg);
  color: white;
  border: none;
  transition: background-color 0.3s;
}

#generator:hover {
  background-color: var(--button-hover);
}

#numbers {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 20px;
}

.number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 50px;
  height: 50px;
  margin: 5px;
  border-radius: 50%;
  font-size: 1.5em;
  font-weight: bold;
  color: white;
}