* {
    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-light: #f8f9fa;
    --white: #ffffff;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 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(--white);
}

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

/* Header */
.header {
    background: var(--white);
    box-shadow: var(--shadow);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

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

.nav-brand .logo {
    height: 40px;
    width: auto;
}

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

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: var(--transition);
    padding: 0.5rem 0;
}

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

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

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

/* Main Content */
main {
    margin-top: 80px;
}

/* Hero Section */
.hero {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
    padding: 4rem 20px;
    max-width: 1200px;
    margin: 0 auto;
    min-height: 500px;
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-content p {
    font-size: 1.25rem;
    color: var(--text-light);
    margin-bottom: 2rem;
}

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

/* Buttons */
.btn-primary,
.btn-secondary,
.btn-text {
    display: inline-block;
    text-decoration: none;
    font-weight: 600;
    border-radius: var(--border-radius);
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-family: inherit;
}

.btn-primary {
    background: var(--secondary-color);
    color: var(--white);
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

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

.btn-secondary {
    background: transparent;
    color: var(--secondary-color);
    padding: 1rem 2rem;
    border: 2px solid var(--secondary-color);
}

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

.btn-text {
    color: var(--secondary-color);
    font-weight: 600;
    padding: 0.5rem 0;
}

.btn-text:hover {
    color: #2980b9;
}

/* Sections */
section {
    padding: 4rem 0;
}

section h2 {
    text-align: center;
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 3rem;
    font-weight: 700;
}

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

.book-card {
    background: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

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

.book-card-image {
    height: 200px;
    background: var(--background-light);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.book-card-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.book-card-content {
    padding: 1.5rem;
}

.book-card h3 {
    font-size: 1.25rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.book-card .author {
    color: var(--text-light);
    margin-bottom: 1rem;
    font-style: italic;
}

.book-card .category {
    display: inline-block;
    background: var(--background-light);
    color: var(--text-color);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    margin-bottom: 1rem;
}

.book-card p {
    color: var(--text-color);
    margin-bottom: 1.5rem;
    line-height: 1.5;
}

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

.category-card {
    background: var(--white);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

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

.category-card h3 {
    color: var(--primary-color);
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.category-card p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

/* Book Detail */
.book-detail {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem 20px;
}

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

.book-detail-image {
    background: var(--background-light);
    border-radius: var(--border-radius);
    padding: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 400px;
}

.book-detail-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.book-detail-info h1 {
    color: var(--primary-color);
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.book-detail-info .author {
    font-size: 1.25rem;
    color: var(--text-light);
    margin-bottom: 1rem;
    font-style: italic;
}

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

.book-detail-info .category,
.book-detail-info .year {
    background: var(--background-light);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
}

.book-detail-content h3 {
    color: var(--primary-color);
    font-size: 1.5rem;
    margin: 2rem 0 1rem 0;
}

.book-detail-content p {
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.book-detail-content ul {
    margin: 1rem 0 2rem 0;
    padding-left: 1.5rem;
}

.book-detail-content li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.external-links {
    display: flex;
    gap: 1rem;
    margin: 2rem 0;
    flex-wrap: wrap;
}

.disclaimer-note {
    background: var(--background-light);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    border-left: 4px solid var(--secondary-color);
    margin: 2rem 0;
}

/* Search and Filter */
.search-filter {
    background: var(--background-light);
    padding: 2rem;
    border-radius: var(--border-radius);
    margin-bottom: 3rem;
}

.search-filter-row {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 1rem;
    align-items: end;
}

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

.form-group label {
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-color);
}

.form-group input,
.form-group select {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--secondary-color);
}

/* Forms */
.contact-form {
    max-width: 600px;
    margin: 0 auto;
}

.contact-form .form-group {
    margin-bottom: 1.5rem;
}

.contact-form textarea {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-family: inherit;
    resize: vertical;
    min-height: 120px;
}

.contact-form textarea:focus {
    outline: none;
    border-color: var(--secondary-color);
}

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

.text-left {
    text-align: left;
}

.content-page {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 20px;
}

.content-page h1 {
    color: var(--primary-color);
    font-size: 2.5rem;
    margin-bottom: 2rem;
}

.content-page h2 {
    color: var(--primary-color);
    font-size: 1.75rem;
    margin: 2rem 0 1rem 0;
}

.content-page h3 {
    color: var(--primary-color);
    font-size: 1.25rem;
    margin: 1.5rem 0 0.75rem 0;
}

.content-page p {
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.content-page ul,
.content-page ol {
    margin: 1rem 0 2rem 0;
    padding-left: 2rem;
}

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

.contact-info {
    background: var(--background-light);
    padding: 2rem;
    border-radius: var(--border-radius);
    margin: 2rem 0;
}

.contact-info h3 {
    margin-top: 0;
}

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

/* Cookie Banner */
.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--primary-color);
    color: var(--white);
    padding: 1rem;
    z-index: 1001;
    box-shadow: 0 -2px 10px rgba(0,0,0,0.1);
}

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

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

.cookie-content .btn-primary {
    background: var(--white);
    color: var(--primary-color);
    padding: 0.75rem 1.5rem;
    white-space: nowrap;
}

/* Footer */
.footer {
    background: var(--primary-color);
    color: var(--white);
    padding: 3rem 0 1rem 0;
    margin-top: 4rem;
}

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

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

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

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

.footer-section a {
    color: var(--white);
    text-decoration: none;
    opacity: 0.8;
    transition: var(--transition);
}

.footer-section a:hover {
    opacity: 1;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.2);
    padding-top: 2rem;
    text-align: center;
    opacity: 0.8;
}

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

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

    .nav-menu li {
        width: 100%;
        text-align: center;
        padding: 0.5rem 0;
    }

    .nav-toggle {
        display: flex;
    }

    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        padding: 2rem 20px;
    }

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

    .books-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .categories-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

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

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

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

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

    .cookie-content {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
    }

    section {
        padding: 2rem 0;
    }

    section h2 {
        font-size: 2rem;
    }
}

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

    .nav-container {
        padding: 1rem 15px;
    }

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

    .hero-content p {
        font-size: 1rem;
    }

    section h2 {
        font-size: 1.75rem;
    }

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

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