* {
    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 Styles */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.logo, .footer-logo {
    width: 32px;
    height: 32px;
}

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

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

.nav-link {
    text-decoration: none;
    color: #64748b;
    font-weight: 500;
    transition: color 0.3s ease;
}

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

.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    flex-direction: column;
    gap: 4px;
}

.nav-toggle span {
    width: 24px;
    height: 3px;
    background: #333;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    position: relative;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 6rem 0;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0.1;
    z-index: 1;
}

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

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

/* Button Styles */
.btn {
    display: inline-block;
    padding: 0.75rem 2rem;
    border: none;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
}

.btn-secondary {
    background: #f8fafc;
    color: #475569;
    border: 2px solid #e2e8f0;
}

.btn-secondary:hover {
    background: #e2e8f0;
    transform: translateY(-2px);
}

/* Section Styles */
.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: #1e293b;
}

.featured-books,
.categories-preview {
    padding: 5rem 0;
}

.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: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    text-decoration: none;
    color: inherit;
}

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

.book-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    background: #f1f5f9;
}

.book-content {
    padding: 1.5rem;
}

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

.book-author {
    color: #64748b;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.book-category {
    display: inline-block;
    background: #e0f2fe;
    color: #0369a1;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 1rem;
}

.book-description {
    color: #64748b;
    line-height: 1.6;
}

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

.category-card {
    background: white;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
    padding: 2rem;
    text-align: center;
    transition: all 0.3s ease;
    text-decoration: none;
    color: inherit;
}

.category-card:hover {
    border-color: #2563eb;
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
}

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

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

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

.search-controls {
    display: flex;
    gap: 1rem;
    max-width: 600px;
    margin: 0 auto;
    flex-wrap: wrap;
}

.search-input,
.filter-select {
    flex: 1;
    padding: 0.75rem;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    min-width: 200px;
}

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

/* Book Detail Page */
.book-detail {
    padding: 3rem 0;
}

.book-detail-container {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.book-detail-image {
    width: 100%;
    max-width: 400px;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 8px 30px rgba(0,0,0,0.15);
}

.book-detail-info h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    color: #1e293b;
}

.book-detail-author {
    font-size: 1.25rem;
    color: #64748b;
    margin-bottom: 1rem;
}

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

.book-detail-description {
    font-size: 1.125rem;
    line-height: 1.7;
    margin-bottom: 2rem;
    color: #475569;
}

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

.external-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: #f8fafc;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    text-decoration: none;
    color: #475569;
    font-weight: 500;
    transition: all 0.3s ease;
}

.external-link:hover {
    background: #e2e8f0;
    border-color: #cbd5e1;
}

.disclaimer-note {
    background: #fef3c7;
    border: 1px solid #f59e0b;
    border-radius: 8px;
    padding: 1rem;
    margin: 2rem 0;
    color: #92400e;
}

.key-takeaways,
.who-its-for {
    margin-bottom: 3rem;
}

.key-takeaways h3,
.who-its-for h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #1e293b;
}

.takeaways-list {
    list-style: none;
}

.takeaways-list li {
    position: relative;
    padding-left: 2rem;
    margin-bottom: 0.75rem;
    color: #475569;
}

.takeaways-list li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #059669;
    font-weight: bold;
}

/* Footer */
.footer {
    background: #1e293b;
    color: #cbd5e1;
    padding: 3rem 0 1rem;
}

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

.footer-section h3 {
    color: white;
    margin-bottom: 1rem;
    font-size: 1.125rem;
    font-weight: 600;
}

.footer-links {
    list-style: none;
}

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

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

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

.footer-description {
    margin-top: 1rem;
    color: #94a3b8;
}

.contact-info p {
    margin-bottom: 0.5rem;
}

.contact-info a {
    color: #cbd5e1;
    text-decoration: none;
}

.contact-info a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 1rem;
    text-align: center;
    color: #94a3b8;
}

/* Cookie Banner */
.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: #1e293b;
    color: white;
    padding: 1rem;
    z-index: 10000;
    box-shadow: 0 -2px 10px rgba(0,0,0,0.1);
}

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

.cookie-content p {
    flex: 1;
    margin: 0;
    min-width: 300px;
}

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

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

.form-input,
.form-textarea {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

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

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

/* Content Pages */
.content-page {
    padding: 3rem 0;
}

.content-page h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 2rem;
    color: #1e293b;
}

.content-page h2 {
    font-size: 2rem;
    font-weight: 700;
    margin: 2rem 0 1rem;
    color: #1e293b;
}

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

.content-page p {
    margin-bottom: 1rem;
    line-height: 1.7;
    color: #475569;
}

.content-page ul,
.content-page ol {
    margin-bottom: 1rem;
    padding-left: 2rem;
    color: #475569;
}

.content-page li {
    margin-bottom: 0.5rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 100%;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 2rem;
        box-shadow: 0 2px 10px rgba(0,0,0,0.1);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .nav-toggle {
        display: flex;
    }

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

    .hero-subtitle {
        font-size: 1.125rem;
    }

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

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

    .book-detail-container {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .search-controls {
        flex-direction: column;
    }

    .search-input,
    .filter-select {
        min-width: 100%;
    }

    .book-links {
        flex-direction: column;
    }

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

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

    .cookie-content p {
        min-width: 100%;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .nav {
        padding: 1rem;
    }

    .hero {
        padding: 4rem 0;
    }

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

    .featured-books,
    .categories-preview {
        padding: 3rem 0;
    }

    .book-content {
        padding: 1rem;
    }
}