/* Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Arial, Helvetica, sans-serif;
}

/* Common layout */
body {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  transition:
    background-color 0.4s ease,
    color 0.4s ease;
}

.container {
  text-align: center;
}

/* Button */
#toggle-btn {
  margin-top: 20px;
  padding: 12px 30px;
  font-size: 16px;
  border-radius: 25px;
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
}

/* LIGHT THEME */
body.light {
  background-color: #f5f7fa;
  color: #222;
}

body.light #toggle-btn {
  background-color: #222;
  color: #fff;
}

/* DARK THEME */
body.dark {
  background-color: #121212;
  color: #f1f1f1;
}

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