* {
    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: #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;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

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

.logo img {
    margin-right: 0.5rem;
}

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

.nav a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.nav a:hover {
    color: #2c5aa0;
}

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

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 2px 0;
    transition: 0.3s;
}

/* Hero */
.hero {
    padding: 4rem 0;
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    color: #1e293b;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero p {
    font-size: 1.25rem;
    color: #64748b;
    margin-bottom: 2rem;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: 2px solid transparent;
    cursor: pointer;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: #1e3a8a;
    transform: translateY(-2px);
}

.btn-secondary {
    background: #64748b;
    color: white;
}

.btn-secondary:hover {
    background: #475569;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: #2c5aa0;
    border-color: #2c5aa0;
}

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

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

.featured-books h2, .categories-preview h2 {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 1rem;
}

.section-subtitle {
    text-align: center;
    font-size: 1.125rem;
    color: #64748b;
    margin-bottom: 3rem;
}

.section-footer {
    text-align: center;
    margin-top: 3rem;
}

/* 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: 0.75rem;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
}

.book-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.15);
}

.book-image {
    width: 100%;
    height: 200px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}

.book-image img {
    width: 80px;
    height: auto;
}

.book-content {
    padding: 1.5rem;
}

.book-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 0.5rem;
}

.book-author {
    color: #64748b;
    margin-bottom: 0.5rem;
}

.book-category {
    display: inline-block;
    background: #e2e8f0;
    color: #475569;
    padding: 0.25rem 0.75rem;
    border-radius: 1rem;
    font-size: 0.875rem;
    margin-bottom: 1rem;
}

.book-description {
    color: #64748b;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.book-actions {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

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

.category-card {
    background: white;
    border-radius: 0.75rem;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    padding: 2rem;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
    text-decoration: none;
    color: inherit;
}

.category-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.15);
}

.category-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #2c5aa0, #1e3a8a);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
    color: white;
    font-size: 1.5rem;
    font-weight: bold;
}

.category-name {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1e293b;
    margin-bottom: 0.5rem;
}

.category-count {
    color: #64748b;
    font-size: 0.875rem;
}

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

.book-header {
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: 2rem;
    margin-bottom: 3rem;
}

.book-cover {
    width: 200px;
    height: 280px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.book-info h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 1rem;
}

.book-meta {
    margin-bottom: 1.5rem;
}

.book-meta p {
    margin-bottom: 0.5rem;
    color: #64748b;
}

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

.book-sections {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
}

.book-description {
    margin-bottom: 2rem;
}

.book-description h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1e293b;
}

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

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

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

.disclaimer-box {
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    border-radius: 0.5rem;
    padding: 1.5rem;
    margin: 2rem 0;
}

.disclaimer-box h3 {
    color: #1e293b;
    margin-bottom: 0.5rem;
}

/* Search and Filter */
.search-filter {
    background: #f8fafc;
    padding: 2rem 0;
    margin-bottom: 2rem;
}

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

.search-input {
    flex: 1;
    min-width: 250px;
    padding: 0.75rem 1rem;
    border: 1px solid #d1d5db;
    border-radius: 0.5rem;
    font-size: 1rem;
}

.filter-select {
    padding: 0.75rem 1rem;
    border: 1px solid #d1d5db;
    border-radius: 0.5rem;
    font-size: 1rem;
    background: white;
    min-width: 150px;
}

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

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

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #d1d5db;
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-control:focus {
    outline: none;
    border-color: #2c5aa0;
    box-shadow: 0 0 0 3px rgba(44, 90, 160, 0.1);
}

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

/* Footer */
.footer {
    background: #1e293b;
    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-logo {
    display: flex;
    align-items: center;
    margin-bottom: 1rem;
    font-weight: 700;
    font-size: 1.25rem;
}

.footer-logo img {
    margin-right: 0.5rem;
}

.footer-section h3 {
    margin-bottom: 1rem;
    color: white;
}

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

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

.footer-section a {
    color: #cbd5e1;
    text-decoration: none;
    transition: color 0.3s;
}

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

.footer-bottom {
    border-top: 1px solid #334155;
    padding-top: 1rem;
    text-align: center;
    color: #cbd5e1;
}

/* Cookie Banner */
.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: #1e293b;
    color: white;
    padding: 1rem;
    z-index: 1000;
    transform: translateY(100%);
    transition: transform 0.3s;
}

.cookie-banner.show {
    transform: translateY(0);
}

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

.cookie-btn {
    background: #2c5aa0;
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 0.25rem;
    cursor: pointer;
    font-weight: 600;
}

.cookie-btn:hover {
    background: #1e3a8a;
}

/* Content Pages */
.content-page {
    padding: 3rem 0;
    max-width: 800px;
    margin: 0 auto;
}

.content-page h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 2rem;
}

.content-page h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1e293b;
    margin: 2rem 0 1rem;
}

.content-page h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1e293b;
    margin: 1.5rem 0 0.75rem;
}

.content-page p {
    margin-bottom: 1rem;
    line-height: 1.7;
    color: #374151;
}

.content-page ul, .content-page ol {
    margin-bottom: 1rem;
    padding-left: 2rem;
}

.content-page li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
    color: #374151;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .books-grid {
        grid-template-columns: 1fr;
    }
    
    .book-header {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .book-cover {
        margin: 0 auto;
    }
    
    .book-sections {
        grid-template-columns: 1fr;
    }
    
    .search-filter-content {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-input, .filter-select {
        min-width: auto;
    }
    
    .cookie-content {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 2rem 0;
    }
    
    .featured-books, .categories-preview {
        padding: 2rem 0;
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        text-align: center;
        max-width: 300px;
    }
}