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

:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --text-color: #333;
    --text-light: #666;
    --border-color: #ddd;
    --background-color: #fff;
    --light-bg: #f8f9fa;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --shadow-hover: 0 5px 20px rgba(0,0,0,0.15);
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
}

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

/* Cookie Banner */
.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--primary-color);
    color: white;
    padding: 15px;
    z-index: 1000;
    transform: translateY(100%);
    transition: var(--transition);
}

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

.cookie-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    gap: 20px;
}

.cookie-btn {
    background: var(--secondary-color);
    color: white;
    border: none;
    padding: 8px 20px;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 500;
    white-space: nowrap;
}

/* Header */
.header {
    background: var(--background-color);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--primary-color);
}

.logo {
    width: 40px;
    height: 40px;
}

.brand-name {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

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

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--secondary-color);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--secondary-color);
}

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

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: var(--primary-color);
    margin: 3px 0;
    transition: var(--transition);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--light-bg) 0%, #fff 100%);
    padding: 80px 20px;
    display: flex;
    align-items: center;
    min-height: 70vh;
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-light);
    margin-bottom: 2rem;
    line-height: 1.5;
}

.cta-button {
    display: inline-block;
    background: var(--secondary-color);
    color: white;
    padding: 15px 30px;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.cta-button:hover {
    background: #2980b9;
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.secondary-button {
    display: inline-block;
    background: transparent;
    color: var(--secondary-color);
    padding: 12px 24px;
    text-decoration: none;
    border: 2px solid var(--secondary-color);
    border-radius: var(--border-radius);
    font-weight: 600;
    transition: var(--transition);
}

.secondary-button:hover {
    background: var(--secondary-color);
    color: white;
}

.hero-image {
    text-align: center;
}

.hero-bg {
    max-width: 100%;
    height: auto;
}

/* Sections */
.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-align: center;
    margin-bottom: 3rem;
}

.featured-books,
.categories-preview {
    padding: 80px 20px;
}

.categories-preview {
    background: var(--light-bg);
}

/* Books Grid */
.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.book-card {
    background: var(--background-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
    text-decoration: none;
    color: inherit;
}

.book-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.book-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    background: var(--light-bg);
}

.book-info {
    padding: 25px;
}

.book-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 8px;
    line-height: 1.3;
}

.book-author {
    color: var(--text-light);
    margin-bottom: 12px;
    font-style: italic;
}

.book-category {
    display: inline-block;
    background: var(--secondary-color);
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 15px;
}

.book-description {
    color: var(--text-light);
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* Categories Grid */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
}

.category-card {
    background: var(--background-color);
    padding: 30px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
    text-decoration: none;
    color: inherit;
}

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

.category-name {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.category-count {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* Book Detail Page */
.book-detail {
    padding: 40px 20px;
    max-width: 1000px;
    margin: 0 auto;
}

.book-detail-content {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 50px;
    margin-bottom: 40px;
}

.book-detail-image {
    width: 100%;
    height: 400px;
    object-fit: cover;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

.book-detail-info h1 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.book-detail-author {
    font-size: 1.25rem;
    color: var(--text-light);
    font-style: italic;
    margin-bottom: 20px;
}

.book-detail-meta {
    display: flex;
    gap: 15px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.meta-item {
    background: var(--light-bg);
    padding: 8px 15px;
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    color: var(--text-color);
}

.book-description-full {
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--text-color);
    margin-bottom: 30px;
}

.key-takeaways {
    margin-bottom: 30px;
}

.key-takeaways h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 1.3rem;
}

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

.key-takeaways li {
    padding: 8px 0;
    padding-left: 25px;
    position: relative;
}

.key-takeaways li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--secondary-color);
    font-weight: bold;
}

.who-its-for {
    background: var(--light-bg);
    padding: 25px;
    border-radius: var(--border-radius);
    margin-bottom: 30px;
}

.who-its-for h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.external-links {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    margin-bottom: 30px;
}

.external-link {
    display: inline-block;
    padding: 12px 20px;
    background: var(--secondary-color);
    color: white;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: var(--transition);
}

.external-link:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

.disclaimer-note {
    background: #fff3cd;
    border: 1px solid #ffeaa7;
    padding: 20px;
    border-radius: var(--border-radius);
    color: #856404;
    margin-bottom: 30px;
}

/* Search and Filter */
.search-filter {
    background: var(--light-bg);
    padding: 30px 20px;
    margin-bottom: 40px;
}

.search-filter-content {
    max-width: 800px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 20px;
    align-items: end;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-group label {
    font-weight: 500;
    color: var(--text-color);
}

.form-control {
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.search-btn {
    background: var(--secondary-color);
    color: white;
    border: none;
    padding: 12px 25px;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 500;
    transition: var(--transition);
}

.search-btn:hover {
    background: #2980b9;
}

/* Footer */
.footer {
    background: var(--primary-color);
    color: white;
    padding: 50px 20px 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 30px;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 15px;
    color: white;
}

.footer-section p {
    line-height: 1.6;
    color: #bdc3c7;
}

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

.footer-section ul li {
    margin-bottom: 8px;
}

.footer-section ul li a {
    color: #bdc3c7;
    text-decoration: none;
    transition: var(--transition);
}

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

.footer-bottom {
    border-top: 1px solid #34495e;
    padding-top: 20px;
    text-align: center;
    color: #bdc3c7;
}

/* Content Pages */
.content-page {
    padding: 40px 20px;
    max-width: 800px;
    margin: 0 auto;
}

.content-page h1 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 30px;
    text-align: center;
}

.content-page h2 {
    color: var(--primary-color);
    margin: 30px 0 15px;
    font-size: 1.5rem;
}

.content-page h3 {
    color: var(--text-color);
    margin: 25px 0 10px;
    font-size: 1.25rem;
}

.content-page p {
    margin-bottom: 15px;
    line-height: 1.7;
}

.content-page ul,
.content-page ol {
    margin-bottom: 15px;
    padding-left: 30px;
}

.content-page li {
    margin-bottom: 8px;
    line-height: 1.6;
}

/* Contact Form */
.contact-form {
    background: var(--light-bg);
    padding: 40px;
    border-radius: var(--border-radius);
    margin: 40px 0;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 20px;
}

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

.submit-btn {
    background: var(--secondary-color);
    color: white;
    border: none;
    padding: 15px 30px;
    border-radius: var(--border-radius);
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.submit-btn:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

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

.mb-20 {
    margin-bottom: 20px;
}

.mb-30 {
    margin-bottom: 30px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: var(--background-color);
        flex-direction: column;
        justify-content: flex-start;
        align-items: center;
        padding-top: 50px;
        transition: var(--transition);
        box-shadow: var(--shadow);
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }

    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .book-detail-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .book-detail-image {
        max-width: 300px;
        margin: 0 auto;
    }

    .search-filter-content {
        grid-template-columns: 1fr;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .cookie-content {
        flex-direction: column;
        text-align: center;
        gap: 15px;
    }

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

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

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .section-title {
        font-size: 2rem;
    }

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

    .container,
    .nav-container {
        padding: 0 15px;
    }

    .hero,
    .featured-books,
    .categories-preview {
        padding: 60px 15px;
    }
}