* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #2c3e50;
    background-color: #f5f7fa;
}

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 3rem 1.5rem;
    box-shadow: 0 4px 20px rgba(102, 126, 234, 0.3);
    position: sticky;
    top: 0;
    z-index: 100;
}

header h1 {
    font-size: 2.5rem;
    text-align: center;
    font-weight: 700;
    letter-spacing: -0.5px;
    margin: 0;
}

main {
    max-width: 900px;
    margin: 3.5rem auto;
    padding: 0 1.5rem;
    min-height: calc(100vh - 300px);
}

section {
    background: white;
    padding: 3rem;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    margin-bottom: 2.5rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

section:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
}

section h3 {
    color: #667eea;
    font-size: 1.5rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    font-weight: 600;
    border-bottom: 2px solid #e2e8f0;
    padding-bottom: 0.5rem;
}

section p {
    margin-bottom: 1.75rem;
    line-height: 1.9;
    color: #34495e;
    font-size: 1.05rem;
}

section ul {
    list-style: none;
    margin-bottom: 2rem;
}

section li {
    margin-bottom: 0.75rem;
}

section a {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    position: relative;
}

section a:hover {
    color: #764ba2;
    text-decoration: underline;
}

/* Styling for nested unordered lists */
section ul ul {
    margin-left: 1.5rem; /* Indent nested unordered lists */
    list-style: disc; /* Re-introduce disc bullets for nested lists */
    margin-top: 0.5rem;
    margin-bottom: 0.5rem;
}

section ul ul li {
    margin-bottom: 0.25rem; /* Adjust spacing for nested list items */
}

/* Responsive Design */
 @media (max-width: 768px) {
    header {
        padding: 2rem 1rem;
    }

    header h1 {
        font-size: 1.8rem;
    }

    section {
        padding: 2rem;
    }

    main {
        margin: 2rem auto;
    }
}

 @media (max-width: 480px) {
    header h1 {
        font-size: 1.5rem;
    }

    section {
        padding: 1.5rem;
    }
}