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

body {
  font-family: Arial, sans-serif;
  line-height: 1.6;
  color: #333;
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
  background-color: #f5f5f5;
}

header {
  text-align: center;
  padding: 20px 0;
  margin-bottom: 30px;
  background-color: #1a237e;
  color: white;
  border-radius: 5px;
}

header h1 {
  margin-bottom: 10px;
}

main {
  display: flex;
  flex-wrap: wrap;
  gap: 30px;
  justify-content: center;
}

@media (min-width: 768px) {
  main {
    grid-template-columns: 2fr 1fr;
  }
}

section {
  background-color: white;
  padding: 20px;
  border-radius: 5px;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  width: 100%;
  max-width: 500px;
}

section h3 {
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 1px solid #ddd;
  color: #1a237e;
}

.activity-card {
  margin-bottom: 15px;
  padding: 15px;
  border: 1px solid #ddd;
  border-radius: 5px;
  background-color: #f9f9f9;
}

.activity-card h4 {
  margin-bottom: 10px;
  color: #0066cc;
}

.activity-card p {
  margin-bottom: 8px;
}

.form-group {
  margin-bottom: 15px;
}

.form-group label {
  display: block;
  margin-bottom: 5px;
  font-weight: bold;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 4px;
  font-size: 16px;
}

button {
  background-color: #1a237e;
  color: white;
  border: none;
  padding: 10px 15px;
  font-size: 16px;
  border-radius: 5px;
  cursor: pointer;
  transition: background-color 0.2s;
}

button:hover {
  background-color: #3949ab;
}

.message {
  margin-top: 20px;
  padding: 10px;
  border-radius: 4px;
}

.success {
  background-color: #e8f5e9;
  color: #2e7d32;
  border: 1px solid #a5d6a7;
}

.error {
  background-color: #ffebee;
  color: #c62828;
  border: 1px solid #ef9a9a;
}

.info {
  background-color: #d1ecf1;
  color: #0c5460;
  border: 1px solid #bee5eb;
}

.hidden {
  display: none;
}

footer {
  text-align: center;
  margin-top: 30px;
  padding: 20px;
  color: #666;
}