/* Global page styling */
body {
  font-family: Arial, sans-serif;
  background: #f5f5f5;
  margin: 0;
  padding: 0;
}

/* Header */
header {
  background: #333;
  color: white;
  padding: 20px;
  text-align: center;
}

/* Navigation bar */
nav {
  background: #444;
  padding: 10px;
  text-align: center;
}

nav a {
  color: white;
  margin: 0 15px;
  text-decoration: none;
  font-weight: bold;
}

nav a:hover {
  text-decoration: underline;
}

/* Main content area */
.content {
  padding: 20px;
}

/* Lesson boxes */
.lesson-box {
  background: white;
  padding: 15px;
  margin-bottom: 15px;
  border-radius: 6px;
  border: 1px solid #ddd;
}