:root {
  --background-color-light: #f0f0f0;
  --text-color-light: #333;
  --container-bg-light: #fff;
  --button-bg-light: #007bff;
  --button-text-light: #fff;
  --number-bg-light: #e9ecef;

  --background-color-dark: #121212;
  --text-color-dark: #f0f0f0;
  --container-bg-dark: #1e1e1e;
  --button-bg-dark: #0056b3;
  --button-text-dark: #f0f0f0;
  --number-bg-dark: #333;
}

body {
  font-family: sans-serif;
  transition: background-color 0.3s, color 0.3s;
}

body.light-mode {
  background-color: var(--background-color-light);
  color: var(--text-color-light);
}

body.dark-mode {
  background-color: var(--background-color-dark);
  color: var(--text-color-dark);
}

.container {
  max-width: 600px;
  margin: 50px auto;
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
  transition: background-color 0.3s;
}

body.light-mode .container {
  background-color: var(--container-bg-light);
}

body.dark-mode .container {
  background-color: var(--container-bg-dark);
}

.theme-switcher {
  text-align: right;
}

#generate-btn {
  display: block;
  width: 100%;
  padding: 10px;
  margin: 20px 0;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  font-size: 16px;
  transition: background-color 0.3s;
}

body.light-mode #generate-btn {
  background-color: var(--button-bg-light);
  color: var(--button-text-light);
}

body.dark-mode #generate-btn {
  background-color: var(--button-bg-dark);
  color: var(--button-text-dark);
}

#lotto-numbers-container {
  margin-top: 20px;
}

.lotto-set {
  display: flex;
  justify-content: center;
  margin-bottom: 10px;
}

.lotto-number {
  display: inline-block;
  width: 40px;
  height: 40px;
  line-height: 40px;
  text-align: center;
  border-radius: 50%;
  margin: 0 5px;
  font-weight: bold;
  transition: background-color 0.3s, color 0.3s;
}

body.light-mode .lotto-number {
  background-color: var(--number-bg-light);
  color: var(--text-color-light);
}

body.dark-mode .lotto-number {
  background-color: var(--number-bg-dark);
  color: var(--text-color-dark);
}