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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

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

/* Header */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: #2c5aa0;
    font-weight: 700;
    font-size: 1.25rem;
    gap: 0.5rem;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-link:hover,
.nav-link.active {
    color: #2c5aa0;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-primary {
    background: #2c5aa0;
    color: white;
}

.btn-primary:hover {
    background: #1e3d6f;
}

.btn-secondary {
    background: #f8f9fa;
    color: #333;
    border: 2px solid #dee2e6;
}

.btn-secondary:hover {
    background: #e9ecef;
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

/* Sections */
.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    color: #2c5aa0;
}

.section-subtitle {
    text-align: center;
    font-size: 1.1rem;
    color: #666;
    margin-bottom: 3rem;
}

.featured-books,
.categories-preview {
    padding: 4rem 0;
}

/* Books Grid */
.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.book-card {
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    transition: transform 0.2s, box-shadow 0.2s;
}

.book-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.book-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.book-content {
    padding: 1.5rem;
}

.book-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: #2c5aa0;
}

.book-author {
    color: #666;
    margin-bottom: 0.5rem;
}

.book-category {
    display: inline-block;
    background: #e3f2fd;
    color: #1565c0;
    padding: 0.25rem 0.75rem;
    border-radius: 15px;
    font-size: 0.875rem;
    margin-bottom: 1rem;
}

.book-description {
    color: #666;
    margin-bottom: 1rem;
    line-height: 1.5;
}

.book-actions {
    display: flex;
    gap: 0.5rem;
}

/* Categories Grid */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.category-card {
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    padding: 2rem;
    text-align: center;
    transition: transform 0.2s;
    text-decoration: none;
    color: inherit;
}

.category-card:hover {
    transform: translateY(-3px);
}

.category-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.category-name {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #2c5aa0;
}

.category-count {
    color: #666;
    font-size: 0.9rem;
}

/* Search and Filters */
.search-filters {
    background: #f8f9fa;
    padding: 2rem 0;
    margin-bottom: 2rem;
}

.search-bar {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.search-input {
    flex: 1;
    min-width: 300px;
    padding: 0.75rem;
    border: 2px solid #dee2e6;
    border-radius: 5px;
    font-size: 1rem;
}

.search-input:focus {
    outline: none;
    border-color: #2c5aa0;
}

.filter-buttons {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 0.5rem 1rem;
    background: white;
    border: 2px solid #dee2e6;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.2s;
}

.filter-btn:hover,
.filter-btn.active {
    background: #2c5aa0;
    color: white;
    border-color: #2c5aa0;
}

/* Book Detail */
.book-detail {
    padding: 2rem 0;
}

.book-detail-content {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.book-detail-image {
    width: 100%;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.book-meta h1 {
    font-size: 2.5rem;
    color: #2c5aa0;
    margin-bottom: 1rem;
}

.book-meta .author {
    font-size: 1.25rem;
    color: #666;
    margin-bottom: 1rem;
}

.book-meta .year {
    color: #999;
    margin-bottom: 1rem;
}

.book-links {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
    flex-wrap: wrap;
}

.external-link {
    padding: 0.75rem 1.5rem;
    background: #28a745;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 600;
    transition: background 0.2s;
}

.external-link:hover {
    background: #218838;
}

.book-sections {
    display: grid;
    gap: 2rem;
}

.book-section h2 {
    color: #2c5aa0;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.takeaways-list {
    list-style: none;
    padding-left: 0;
}

.takeaways-list li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.takeaways-list li:before {
    content: "•";
    color: #2c5aa0;
    font-weight: bold;
    position: absolute;
    left: 0;
}

.disclaimer-notice {
    background: #f8f9fa;
    border-left: 4px solid #2c5aa0;
    padding: 1rem;
    margin: 2rem 0;
    border-radius: 0 5px 5px 0;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #333;
}

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid #dee2e6;
    border-radius: 5px;
    font-size: 1rem;
    font-family: inherit;
}

.form-control:focus {
    outline: none;
    border-color: #2c5aa0;
}

textarea.form-control {
    min-height: 120px;
    resize: vertical;
}

/* Footer */
.footer {
    background: #2c3e50;
    color: white;
    padding: 3rem 0 1rem;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: #ecf0f1;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.2s;
}

.footer-section a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid #34495e;
    padding-top: 1rem;
    text-align: center;
    color: #bdc3c7;
}

/* Cookie Banner */
.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: #2c3e50;
    color: white;
    padding: 1rem;
    z-index: 1000;
}

.cookie-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    gap: 1rem;
}

.cookie-content p {
    margin: 0;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mb-2 {
    margin-bottom: 1rem;
}

.mb-3 {
    margin-bottom: 1.5rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .books-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .book-detail-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .book-detail-image {
        max-width: 300px;
        margin: 0 auto;
    }
    
    .search-input {
        min-width: 250px;
    }
    
    .cookie-content {
        flex-direction: column;
        text-align: center;
    }
    
    .book-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 2rem 0;
    }
    
    .hero-content h1 {
        font-size: 1.75rem;
    }
    
    .featured-books,
    .categories-preview {
        padding: 2rem 0;
    }
    
    .book-card {
        margin-bottom: 1rem;
    }
    
    .search-input {
        min-width: 200px;
    }
}