* {
    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;
}

/* Cookie Banner */
.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: #333;
    color: white;
    padding: 1rem;
    z-index: 1000;
}

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

.cookie-content p {
    flex: 1;
    margin: 0;
}

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

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-brand {
    display: flex;
    align-items: center;
}

.brand-link {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: #333;
}

.logo {
    width: 40px;
    height: 40px;
    margin-right: 10px;
}

.brand-text {
    font-size: 1.5rem;
    font-weight: 700;
    color: #2563eb;
}

.nav-menu {
    display: flex;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #666;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-link:hover,
.nav-link.active {
    color: #2563eb;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

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

/* Buttons */
.btn-primary {
    background: #2563eb;
    color: white;
    padding: 12px 24px;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 600;
    display: inline-block;
    transition: background 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    background: #1d4ed8;
}

.btn-secondary {
    background: transparent;
    color: #2563eb;
    padding: 8px 16px;
    text-decoration: none;
    border: 2px solid #2563eb;
    border-radius: 6px;
    font-weight: 600;
    display: inline-block;
    transition: all 0.3s;
}

.btn-secondary:hover {
    background: #2563eb;
    color: white;
}

/* Hero Section */
.hero {
    padding: 80px 20px;
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    min-height: 500px;
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 800;
    color: #1f2937;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: #6b7280;
    margin-bottom: 2rem;
    line-height: 1.5;
}

.hero-image img {
    width: 100%;
    height: auto;
    max-width: 500px;
}

/* Featured Section */
.featured-section {
    padding: 80px 20px;
    background: #f9fafb;
}

.featured-section h2 {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    color: #1f2937;
}

.section-subtitle {
    text-align: center;
    font-size: 1.125rem;
    color: #6b7280;
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Books Grid */
.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.book-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid #e5e7eb;
}

.book-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}

.book-image {
    height: 200px;
    overflow: hidden;
    background: #f3f4f6;
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.book-content {
    padding: 1.5rem;
}

.book-category {
    background: #dbeafe;
    color: #1e40af;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
}

.book-content h3 {
    margin: 1rem 0 0.5rem 0;
    font-size: 1.25rem;
    font-weight: 700;
}

.book-content h3 a {
    text-decoration: none;
    color: #1f2937;
}

.book-content h3 a:hover {
    color: #2563eb;
}

.book-author {
    color: #6b7280;
    font-weight: 500;
    margin-bottom: 1rem;
}

.book-description {
    color: #4b5563;
    margin-bottom: 1.5rem;
    line-height: 1.5;
}

/* Categories Preview */
.categories-preview {
    padding: 80px 20px;
}

.categories-preview h2 {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: #1f2937;
}

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

.category-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-decoration: none;
    color: #333;
    border: 2px solid #e5e7eb;
    transition: all 0.3s;
}

.category-card:hover {
    border-color: #2563eb;
    transform: translateY(-2px);
}

.category-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: #2563eb;
}

.category-card p {
    color: #6b7280;
}

/* Search and Filter */
.search-filter-section {
    padding: 2rem 0;
    background: #f9fafb;
    border-bottom: 1px solid #e5e7eb;
}

.search-filter-container {
    display: flex;
    gap: 1rem;
    align-items: center;
    flex-wrap: wrap;
}

.search-input {
    flex: 1;
    min-width: 300px;
    padding: 12px 16px;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 1rem;
}

.search-input:focus {
    outline: none;
    border-color: #2563eb;
}

.filter-select {
    padding: 12px 16px;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 1rem;
    background: white;
}

.filter-select:focus {
    outline: none;
    border-color: #2563eb;
}

/* Book Details */
.book-details {
    padding: 40px 20px;
}

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

.book-cover {
    width: 100%;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}

.book-info h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    color: #1f2937;
}

.book-meta {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 2rem;
}

.book-meta span {
    color: #6b7280;
}

.book-meta strong {
    color: #1f2937;
}

.external-links {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.book-content-section {
    margin-bottom: 3rem;
}

.book-content-section h2 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #1f2937;
}

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

.key-takeaways li {
    padding: 0.75rem 0;
    border-bottom: 1px solid #e5e7eb;
    position: relative;
    padding-left: 2rem;
}

.key-takeaways li:before {
    content: "→";
    position: absolute;
    left: 0;
    color: #2563eb;
    font-weight: bold;
}

.disclaimer-note {
    background: #fef3c7;
    border: 1px solid #f59e0b;
    padding: 1rem;
    border-radius: 8px;
    margin: 2rem 0;
}

.disclaimer-note p {
    margin: 0;
    color: #92400e;
    font-weight: 500;
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #374151;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: #2563eb;
}

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

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    padding: 3rem 0 1rem;
}

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

.footer-section h4 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: white;
}

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

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

.footer-section a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.3s;
}

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

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 1rem;
    text-align: center;
    color: #9ca3af;
}

/* Utilities */
.text-center {
    text-align: center;
}

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

.mb-4 {
    margin-bottom: 2rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem;
        box-shadow: 0 2px 10px rgba(0,0,0,0.1);
        gap: 1rem;
    }

    .nav-menu.active {
        display: flex;
    }

    .nav-toggle {
        display: flex;
    }

    .hero {
        grid-template-columns: 1fr;
        gap: 3rem;
        text-align: center;
        padding: 40px 20px;
    }

    .hero-content h1 {
        font-size: 2rem;
    }

    .book-header {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }

    .book-info h1 {
        font-size: 2rem;
    }

    .search-filter-container {
        flex-direction: column;
    }

    .search-input {
        min-width: auto;
    }

    .cookie-content {
        flex-direction: column;
        text-align: center;
    }

    .external-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .books-grid {
        grid-template-columns: 1fr;
    }

    .categories-grid {
        grid-template-columns: 1fr;
    }

    .hero-content h1 {
        font-size: 1.75rem;
    }

    .featured-section h2,
    .categories-preview h2 {
        font-size: 2rem;
    }
}