body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

.header {
    text-align: center;
    color: white;
    margin-bottom: 40px;
}

.header h1 {
    font-size: 3em;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.header p {
    font-size: 1.2em;
    opacity: 0.9;
}

.nav-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.nav-button {
    background: white;
    border: none;
    border-radius: 15px;
    padding: 30px 20px;
    text-decoration: none;
    color: #333;
    font-size: 1.1em;
    font-weight: bold;
    text-align: center;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    cursor: pointer;
    display: block;
}

.nav-button:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
    background: #f8f9fa;
}

.nav-button:active {
    transform: translateY(-2px);
}

.category-section {
    margin-bottom: 40px;
}

.category-title {
    color: white;
    font-size: 1.5em;
    margin-bottom: 20px;
    text-align: center;
    font-weight: bold;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.3);
}

/* Different colors for different categories */
.general .nav-button {
    border-left: 5px solid #28a745;
}

.specialized .nav-button {
    border-left: 5px solid #007bff;
}

.general .nav-button:hover {
    border-left-color: #1e7e34;
}

.specialized .nav-button:hover {
    border-left-color: #0056b3;
}