* {
    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: 1000;
}

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

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

.logo {
    width: 40px;
    height: 40px;
    margin-right: 12px;
}

.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: #666;
    font-weight: 500;
    transition: color 0.3s ease;
    padding: 0.5rem 0;
}

.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;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 80px 0;
    position: relative;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    right: 0;
    width: 50%;
    height: 100%;
    opacity: 0.1;
}

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

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 600px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

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

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    cursor: pointer;
    font-size: 1rem;
}

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

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

.btn-secondary {
    background: transparent;
    color: white;
    border-color: white;
}

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

.btn-outline {
    background: transparent;
    color: #2563eb;
    border-color: #2563eb;
}

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

/* Sections */
.featured-section,
.categories-section {
    padding: 80px 0;
}

.categories-section {
    background: #f8fafc;
}

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

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

.section-actions {
    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;
    padding: 1.5rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
}

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

.book-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 1rem;
}

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

.book-author {
    font-size: 1rem;
    color: #64748b;
    margin-bottom: 0.5rem;
}

.book-category {
    display: inline-block;
    background: #e0e7ff;
    color: #3730a3;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 1rem;
}

.book-description {
    color: #475569;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

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

.btn-small {
    padding: 8px 16px;
    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: 12px;
    padding: 2rem;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
}

.category-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}

.category-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 1rem;
    background: #f1f5f9;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

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

.category-count {
    color: #64748b;
    margin-bottom: 1rem;
}

.category-link {
    text-decoration: none;
    color: inherit;
}

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

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

.search-input,
.filter-select {
    padding: 12px 16px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-size: 1rem;
    flex: 1;
    min-width: 200px;
}

.search-input:focus,
.filter-select:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

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

.book-detail-content {
    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;
}

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

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

.book-meta span {
    font-size: 1.125rem;
}

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

.key-takeaways {
    margin-bottom: 2rem;
}

.key-takeaways h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1e293b;
}

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

.key-takeaways li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
    color: #475569;
}

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

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

.disclaimer-notice {
    background: #f0f9ff;
    border: 1px solid #bae6fd;
    border-radius: 8px;
    padding: 1rem;
    margin: 2rem 0;
    color: #0c4a6e;
}

/* 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-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #2563eb;
}

.footer-heading {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.footer-text {
    color: #cbd5e1;
    line-height: 1.6;
}

.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-bottom {
    border-top: 1px solid #334155;
    padding-top: 1rem;
    text-align: center;
    color: #94a3b8;
}

/* Cookie Notice */
.cookie-notice {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: #1e293b;
    color: white;
    padding: 1rem;
    z-index: 10000;
    transform: translateY(100%);
    transition: transform 0.3s ease;
}

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

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

.cookie-btn {
    background: #2563eb;
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-weight: 500;
}

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

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

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #374151;
}

.form-input,
.form-textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

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

/* Contact Info */
.contact-info {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
    margin-bottom: 2rem;
}

.contact-item {
    display: flex;
    align-items: center;
    margin-bottom: 1rem;
    gap: 1rem;
}

.contact-icon {
    width: 20px;
    height: 20px;
    color: #2563eb;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0,0,0,0.05);
        padding: 2rem 0;
    }

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

    .nav-toggle {
        display: flex;
    }

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

    .hero-actions {
        justify-content: center;
    }

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

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

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

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

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

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

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

    .nav {
        padding: 1rem;
    }

    .hero {
        padding: 60px 0;
    }

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

    .featured-section,
    .categories-section {
        padding: 60px 0;
    }

    .book-card {
        padding: 1rem;
    }

    .category-card {
        padding: 1.5rem;
    }
}

/* Print Styles */
@media print {
    .header,
    .footer,
    .cookie-notice {
        display: none;
    }

    .main {
        margin: 0;
    }

    .book-card,
    .category-card {
        break-inside: avoid;
    }
}