/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #8b5cf6;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --success-color: #10b981;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
}

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

/* Delivery Banner */
.delivery-banner {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 0.75rem 0;
    text-align: center;
    position: relative;
    z-index: 1001;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.delivery-banner-text {
    margin: 0;
    font-size: 0.9375rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.delivery-icon {
    font-size: 1.125rem;
    animation: bounce 2s infinite;
}

.delivery-banner-text strong {
    font-weight: 600;
    margin: 0 0.25rem;
}

@keyframes bounce {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-3px);
    }
}

/* Navbar Styles */
.navbar {
    background-color: var(--bg-white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 1rem 0;
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    cursor: pointer;
    transition: opacity 0.3s ease;
}

.logo:hover {
    opacity: 0.8;
}

.logo h1 {
    font-size: 1.75rem;
    font-weight: 700;
    line-height: 1.1;
    display: inline-flex;
    flex-direction: column;
    align-items: flex-start;
    letter-spacing: -0.02em;
}

.logo-main {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: block;
    line-height: 1;
    margin-bottom: 1px;
}

.logo-shop {
    color: #4b5563;
    font-size: 0.65rem;
    font-weight: 400;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    margin-top: 2px;
    margin-left: 2px;
    display: block;
    opacity: 0.85;
}

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

.nav-menu a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-menu a:hover {
    color: var(--primary-color);
}

.btn-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.btn-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--text-dark);
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* Hero Section */
.hero {
    padding: 7rem 0 6rem;
    background: linear-gradient(to bottom, #ffffff 0%, #f8fafc 100%);
    min-height: 80vh;
    display: flex;
    align-items: center;
    border-bottom: 1px solid #e2e8f0;
}

.hero-content {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 5rem;
    align-items: center;
}

.hero-text {
    padding: 0;
    position: relative;
}

.hero-text::before {
    content: '';
    position: absolute;
    top: -2rem;
    left: -2rem;
    width: 100px;
    height: 100px;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.08) 0%, transparent 70%);
    border-radius: 50%;
    z-index: -1;
    opacity: 0.5;
}

.hero-title {
    font-size: 3.75rem;
    font-weight: 800;
    color: #0f172a;
    margin-bottom: 1.75rem;
    line-height: 1.1;
    letter-spacing: -0.03em;
    position: relative;
}

.hero-title::after {
    content: '';
    position: absolute;
    bottom: -0.5rem;
    left: 0;
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: #475569;
    line-height: 1.8;
    margin-bottom: 3rem;
    max-width: 600px;
    font-weight: 400;
    padding-left: 0.5rem;
    border-left: 3px solid var(--primary-color);
}

.hero-features {
    display: flex;
    gap: 2rem;
    margin-bottom: 2.5rem;
    flex-wrap: wrap;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1rem;
    color: var(--text-dark);
    font-weight: 500;
}

.feature-icon {
    font-size: 1.5rem;
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.books-showcase {
    position: relative;
    width: 100%;
    height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.book-stack {
    position: relative;
    width: 300px;
    height: 400px;
    filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.1));
}

.book-item {
    position: absolute;
    width: 200px;
    height: 280px;
    border-radius: 16px;
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.15);
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.4s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.book-item:hover {
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.2);
}

.book-item:hover {
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.2);
}

.book-1 {
    background: linear-gradient(135deg, #6366f1, #8b5cf6);
    transform: rotate(-8deg) translateX(-20px);
    z-index: 1;
}

.book-2 {
    background: linear-gradient(135deg, #8b5cf6, #a855f7);
    transform: rotate(0deg);
    z-index: 2;
    left: 50px;
}

.book-3 {
    background: linear-gradient(135deg, #a855f7, #c084fc);
    transform: rotate(8deg) translateX(20px);
    z-index: 3;
    left: 100px;
}

.book-stack:hover .book-1 {
    transform: rotate(-12deg) translateX(-30px) translateY(-10px);
}

.book-stack:hover .book-2 {
    transform: rotate(0deg) translateY(-15px);
}

.book-stack:hover .book-3 {
    transform: rotate(12deg) translateX(30px) translateY(-10px);
}


.hero-buttons {
    display: flex;
    gap: 1.25rem;
    flex-wrap: wrap;
    align-items: center;
    margin-top: 0.5rem;
}

.hero-buttons .btn-primary::before {
    content: '→';
    margin-left: 0.5rem;
    transition: transform 0.25s ease;
    display: inline-block;
}

.hero-buttons .btn-primary:hover::before {
    transform: translateX(4px);
}

.btn-primary,
.btn-secondary {
    padding: 1.125rem 2.25rem;
    font-size: 1.125rem;
    font-weight: 600;
    border: none;
    border-radius: 16px;
    cursor: pointer;
    transition: all 0.25s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.2);
    position: relative;
    overflow: hidden;
}

.btn-primary::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    transform: translate(-50%, -50%);
    transition: width 0.6s ease, height 0.6s ease;
}

.btn-primary:hover::after {
    width: 300px;
    height: 300px;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    color: white;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.btn-secondary {
    background-color: white;
    color: var(--text-dark);
    border: 2px solid #e2e8f0;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    position: relative;
}

.btn-secondary::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 0;
    height: 100%;
    background-color: var(--primary-color);
    transition: width 0.3s ease;
    z-index: -1;
}

.btn-secondary:hover::before {
    width: 100%;
}

.btn-secondary:hover {
    background-color: #f8fafc;
    border-color: var(--primary-color);
    color: var(--primary-color);
    box-shadow: 0 2px 6px rgba(99, 102, 241, 0.1);
}

/* Who Is This For Section */
.who-is-for {
    padding: 5rem 0;
    background-color: var(--bg-white);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 4rem;
    color: var(--text-dark);
    font-weight: 700;
    letter-spacing: -0.02em;
}

.books-section .section-title {
    text-align: left;
}

.target-audience {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2.5rem;
    max-width: 1200px;
    margin: 0 auto;
}

.audience-card {
    background-color: var(--bg-white);
    padding: 2.5rem 2rem;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.audience-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.audience-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 24px -8px rgba(99, 102, 241, 0.15);
    border-color: var(--primary-color);
}

.audience-card:hover::before {
    transform: scaleX(1);
}

.audience-icon {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    display: block;
    line-height: 1;
}

.audience-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
    font-weight: 600;
    letter-spacing: -0.01em;
}

.audience-card p {
    color: var(--text-light);
    line-height: 1.8;
    font-size: 1rem;
    margin: 0;
}

/* Product Details Section */
.product-details {
    padding: 4rem 0;
    background-color: var(--bg-white);
}

.details-tabs {
    display: flex;
    gap: 1rem;
    border-bottom: 2px solid var(--border-color);
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.tab-btn {
    padding: 1rem 2rem;
    background: none;
    border: none;
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-light);
    cursor: pointer;
    border-bottom: 3px solid transparent;
    margin-bottom: -2px;
    transition: all 0.3s ease;
}

.tab-btn:hover {
    color: var(--primary-color);
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.tab-content {
    display: none;
    padding: 2rem 0;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.tab-content h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: var(--text-dark);
}

.tab-content h3 {
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
    color: var(--text-dark);
}

.tab-content p {
    color: var(--text-light);
    margin-bottom: 1rem;
    line-height: 1.8;
    font-size: 1.1rem;
}

.features-list {
    list-style: none;
    padding: 0;
}

.features-list li {
    padding: 1rem;
    margin-bottom: 0.5rem;
    background-color: var(--bg-light);
    border-left: 4px solid var(--primary-color);
    border-radius: 4px;
    color: var(--text-dark);
    font-size: 1.1rem;
}

.content-list {
    display: grid;
    gap: 1.5rem;
}

.chapter {
    padding: 1.5rem;
    background-color: var(--bg-light);
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
    transition: transform 0.3s ease;
}

.chapter:hover {
    transform: translateX(5px);
}

.chapter h3 {
    margin: 0 0 0.5rem 0;
    color: var(--text-dark);
}

.chapter p {
    margin: 0;
    color: var(--text-light);
}

.reviews-list {
    display: grid;
    gap: 1.5rem;
}

.review-card {
    padding: 1.5rem;
    background-color: var(--bg-light);
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.review-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.reviewer-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.avatar {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.25rem;
}

.reviewer-info h4 {
    margin-bottom: 0.25rem;
    color: var(--text-dark);
}

.review-rating {
    color: #fbbf24;
    font-size: 1rem;
}

.review-date {
    color: var(--text-light);
    font-size: 0.875rem;
}

.review-card p {
    color: var(--text-dark);
    line-height: 1.6;
}

/* Buy Now Section */
.buy-now-section {
    padding: 4rem 0;
    background-color: var(--bg-white);
}

.buy-now-subtitle {
    text-align: center;
    font-size: 1.125rem;
    color: var(--text-light);
    margin-bottom: 3rem;
    font-weight: 400;
}

.buy-now-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: center;
    max-width: 1000px;
    margin: 0 auto;
}

.buy-now-main {
    text-align: center;
}

.price-display {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.price-display .old-price {
    font-size: 1.5rem;
    text-decoration: line-through;
    color: var(--text-light);
    opacity: 0.6;
}

.price-display .current-price {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--primary-color);
    letter-spacing: -0.03em;
}

.btn-main-cta {
    display: inline-block;
    padding: 1.25rem 3.5rem;
    font-size: 1.25rem;
    font-weight: 600;
    border-radius: 8px;
    text-decoration: none;
    background-color: var(--primary-color);
    color: white;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.25);
    transition: all 0.3s ease;
}

.btn-main-cta:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(99, 102, 241, 0.35);
    color: white;
}

.payment-methods {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
}

.method-card {
    background-color: var(--bg-light);
    padding: 1.5rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    text-align: center;
    transition: all 0.3s ease;
}

.method-card:hover {
    border-color: var(--primary-color);
    background-color: var(--bg-white);
}

.method-card h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 1rem;
}

.btn-method {
    display: block;
    padding: 0.75rem 1.5rem;
    font-size: 0.9375rem;
    font-weight: 600;
    border-radius: 6px;
    text-decoration: none;
    background-color: var(--primary-color);
    color: white;
    transition: all 0.3s ease;
    text-align: center;
}

.btn-method:hover {
    background-color: var(--primary-dark);
    color: white;
}

.btn-method-alt {
    background-color: #059669;
}

.btn-method-alt:hover {
    background-color: #047857;
}

/* CTA Section */
.cta-section {
    padding: 5rem 0;
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    color: white;
    margin-top: 4rem;
}

.cta-content {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 3rem;
    align-items: start;
    text-align: left;
    max-width: 1200px;
    margin: 0 auto;
}

.cta-column {
    display: flex;
    flex-direction: column;
}

.cta-content h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: white;
}

.cta-content > .cta-column > p {
    font-size: 1.125rem;
    margin: 0;
    opacity: 0.95;
    line-height: 1.7;
    color: white;
}

.cta-content > .cta-column > p + p {
    margin-top: 1rem;
}

.delivery-note {
    font-size: 1rem;
    margin-top: 1.5rem !important;
    padding: 0.875rem 1rem;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    border-left: 3px solid rgba(255, 255, 255, 0.5);
    opacity: 0.9;
}

.cta-price {
    display: flex;
    align-items: baseline;
    gap: 1rem;
    margin: 0;
}

.cta-old-price {
    font-size: 1.25rem;
    text-decoration: line-through;
    opacity: 0.7;
    color: white;
}

.cta-current-price {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: white;
}

.cta-method-card {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0.05));
    padding: 2rem 1.5rem;
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.25);
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    text-align: center;
    height: 100%;
    display: flex;
    flex-direction: column;
}

.cta-method-card:hover {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.1));
    border-color: rgba(255, 255, 255, 0.4);
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

.method-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    display: block;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

.cta-method-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: white;
    margin-bottom: 1.5rem;
    letter-spacing: -0.01em;
}

.method-price {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    padding: 0.75rem;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
}

.method-old-price {
    font-size: 1rem;
    text-decoration: line-through;
    color: rgba(255, 255, 255, 0.6);
}

.method-current-price {
    font-size: 1.75rem;
    font-weight: 700;
    color: white;
    letter-spacing: -0.02em;
}

.btn-cta-method {
    display: block;
    padding: 0.875rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 8px;
    text-decoration: none;
    text-align: center;
    background-color: white;
    color: var(--primary-color);
    transition: all 0.3s ease;
}

.btn-cta-method:hover {
    background-color: #f9fafb;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    color: var(--primary-color);
}

.btn-cta-method-alt {
    background-color: #fef3f2;
    color: #dc2626;
}

.btn-cta-method-alt:hover {
    background-color: #fee2e2;
    color: #dc2626;
}

.btn-cta {
    padding: 1.25rem 3rem;
    font-size: 1.25rem;
    font-weight: 600;
    background-color: white;
    color: var(--primary-color);
    border: none;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    letter-spacing: 0.01em;
    box-shadow: 0 4px 14px 0 rgba(0, 0, 0, 0.15);
    margin-bottom: 1.5rem;
    min-width: 280px;
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

.btn-cta:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px 0 rgba(0, 0, 0, 0.25);
    background-color: #f9fafb;
}

.btn-cta:active {
    transform: translateY(-1px);
    box-shadow: 0 4px 14px 0 rgba(0, 0, 0, 0.15);
}

.cta-guarantee {
    font-size: 0.95rem;
    opacity: 0.9;
    margin: 0;
}

/* Books Section */
.books-section {
    padding: 5rem 0;
    background-color: var(--bg-white);
}

.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 3rem;
    max-width: 1200px;
    margin: 0 auto;
    justify-items: center;
}

.book-card {
    background-color: var(--bg-white);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    max-width: 400px;
    width: 100%;
}

.book-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 12px 24px -8px rgba(99, 102, 241, 0.2);
    border-color: var(--primary-color);
}

.book-card:hover .book-cover-preview {
    transform: rotateY(-5deg) rotateX(2deg);
    transition: transform 0.3s ease;
}

.book-card:hover .book-pages-preview {
    box-shadow: 
        6px 0 16px rgba(0, 0, 0, 0.4),
        12px 0 28px rgba(0, 0, 0, 0.3),
        inset -2px 0 10px rgba(255, 255, 255, 0.15),
        inset 0 3px 6px rgba(255, 255, 255, 0.2);
}

.book-card-image {
    position: relative;
    background: linear-gradient(135deg, #f0f9ff 0%, #e0e7ff 100%);
    padding: 3rem 2rem;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 300px;
}

.book-cover-preview {
    position: relative;
    width: 200px;
    height: 280px;
    perspective: 1200px;
    transform-style: preserve-3d;
}

.book-spine-preview {
    position: absolute;
    left: 0;
    top: 0;
    width: 18px;
    height: 100%;
    background: linear-gradient(90deg, 
        rgba(15, 23, 42, 0.95) 0%,
        rgba(30, 41, 59, 0.9) 50%,
        rgba(15, 23, 42, 0.95) 100%);
    border-radius: 4px 0 0 4px;
    box-shadow: 
        inset -2px 0 8px rgba(0, 0, 0, 0.4),
        -2px 0 4px rgba(0, 0, 0, 0.2);
    z-index: 2;
}

.book-spine-preview::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: 
        repeating-linear-gradient(
            90deg,
            transparent,
            transparent 3px,
            rgba(255, 255, 255, 0.05) 3px,
            rgba(255, 255, 255, 0.05) 4px
        );
    border-radius: 4px 0 0 4px;
}

.book-pages-preview {
    position: absolute;
    left: 18px;
    top: 0;
    width: calc(100% - 18px);
    height: 100%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 0 8px 8px 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: white;
    padding: 2rem;
    box-shadow: 
        4px 0 12px rgba(0, 0, 0, 0.3),
        8px 0 20px rgba(0, 0, 0, 0.2),
        inset -2px 0 8px rgba(255, 255, 255, 0.1),
        inset 0 2px 4px rgba(255, 255, 255, 0.15);
    overflow: hidden;
    position: relative;
    transform: translateZ(0);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

.book-pages-preview::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        repeating-linear-gradient(
            45deg,
            transparent,
            transparent 10px,
            rgba(255, 255, 255, 0.12) 10px,
            rgba(255, 255, 255, 0.12) 20px
        );
    opacity: 1;
    z-index: 1;
}

.book-pages-preview h3,
.book-pages-preview p {
    position: relative;
    z-index: 2;
}

.book-pages-preview h3 {
    font-size: 1.125rem;
    margin-bottom: 0.5rem;
    text-align: center;
    font-weight: 700;
    text-shadow: 
        0 2px 8px rgba(0, 0, 0, 0.5),
        0 1px 3px rgba(0, 0, 0, 0.3),
        0 0 20px rgba(0, 0, 0, 0.2);
    letter-spacing: 0.5px;
    color: #ffffff;
}

.book-pages-preview p {
    font-size: 0.875rem;
    opacity: 0.98;
    text-align: center;
    text-shadow: 
        0 1px 4px rgba(0, 0, 0, 0.4),
        0 0 10px rgba(0, 0, 0, 0.2);
    color: #ffffff;
    font-weight: 500;
}

/* Book 1 - Business/Management Style - Realistic book cover */
.book-cover-1 .book-pages-preview,
.book-pages-1 {
    background: 
        linear-gradient(180deg, 
            rgba(99, 102, 241, 0.88) 0%, 
            rgba(124, 58, 237, 0.85) 30%,
            rgba(139, 92, 246, 0.87) 60%,
            rgba(124, 58, 237, 0.85) 100%),
        url('https://images.unsplash.com/photo-1454165804606-c3d57bc86b40?w=400&q=80') center/cover;
    background-blend-mode: multiply, overlay;
    position: relative;
    overflow: hidden;
}

.book-cover-1 .book-pages-preview::before {
    background: 
        radial-gradient(ellipse at 50% 25%, rgba(255, 255, 255, 0.3) 0%, transparent 55%),
        radial-gradient(ellipse at 50% 75%, rgba(99, 102, 241, 0.25) 0%, transparent 45%),
        linear-gradient(180deg, 
            rgba(99, 102, 241, 0.5) 0%,
            rgba(139, 92, 246, 0.45) 50%,
            rgba(99, 102, 241, 0.5) 100%);
    opacity: 1;
    box-shadow: 
        inset 0 0 80px rgba(255, 255, 255, 0.15),
        inset 0 -40px 60px rgba(0, 0, 0, 0.1);
}

.book-cover-1 .book-pages-preview::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        url('data:image/svg+xml;utf8,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="rgba(255,255,255,0.03)"/><circle cx="75" cy="75" r="1" fill="rgba(255,255,255,0.03)"/><circle cx="50" cy="10" r="0.5" fill="rgba(255,255,255,0.02)"/><circle cx="10" cy="50" r="0.5" fill="rgba(255,255,255,0.02)"/><circle cx="90" cy="30" r="0.5" fill="rgba(255,255,255,0.02)"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>'),
        repeating-linear-gradient(
            0deg,
            transparent,
            transparent 1px,
            rgba(255, 255, 255, 0.02) 1px,
            rgba(255, 255, 255, 0.02) 2px
        );
    z-index: 1;
    pointer-events: none;
    opacity: 0.6;
}

.book-cover-1 .book-spine-preview {
    background: linear-gradient(90deg, 
        rgba(79, 70, 229, 0.95) 0%,
        rgba(99, 102, 241, 0.9) 50%,
        rgba(79, 70, 229, 0.95) 100%);
    box-shadow: 
        inset -3px 0 10px rgba(0, 0, 0, 0.5),
        -3px 0 6px rgba(0, 0, 0, 0.3),
        inset 0 0 20px rgba(99, 102, 241, 0.2);
}

.book-cover-1 .book-pages-preview h3,
.book-cover-1 .book-pages-preview p {
    text-align: center;
    position: relative;
    z-index: 3;
    font-family: 'Georgia', 'Times New Roman', serif;
}

.book-cover-1 .book-pages-preview h3 {
    color: #ffffff;
    text-shadow: 
        0 4px 14px rgba(0, 0, 0, 0.8),
        0 2px 8px rgba(0, 0, 0, 0.6),
        0 1px 4px rgba(0, 0, 0, 0.4),
        0 0 50px rgba(99, 102, 241, 0.5);
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    line-height: 1.3;
}

.book-cover-1 .book-pages-preview p {
    color: rgba(255, 255, 255, 0.95);
    text-shadow: 
        0 3px 10px rgba(0, 0, 0, 0.7),
        0 1px 5px rgba(0, 0, 0, 0.5),
        0 0 30px rgba(139, 92, 246, 0.4);
    font-weight: 500;
    letter-spacing: 0.5px;
    font-size: 0.9rem;
}

/* Book 2 - Career/Growth Style - Realistic book cover */
.book-cover-2 .book-pages-preview,
.book-pages-2 {
    background: 
        linear-gradient(135deg, 
            rgba(16, 185, 129, 0.9) 0%,
            rgba(5, 150, 105, 0.87) 25%,
            rgba(34, 197, 94, 0.88) 50%,
            rgba(5, 150, 105, 0.87) 75%,
            rgba(22, 163, 74, 0.9) 100%),
        url('https://images.unsplash.com/photo-1521737604893-d14cc237f11d?w=400&q=80') center/cover;
    background-blend-mode: multiply, screen;
    position: relative;
    overflow: hidden;
}

.book-cover-2 .book-pages-preview::before {
    background: 
        linear-gradient(135deg, 
            rgba(16, 185, 129, 0.45) 0%,
            rgba(5, 150, 105, 0.4) 50%,
            rgba(34, 197, 94, 0.45) 100%),
        radial-gradient(ellipse at top left, rgba(255, 255, 255, 0.25) 0%, transparent 50%),
        radial-gradient(ellipse at bottom right, rgba(16, 185, 129, 0.2) 0%, transparent 50%);
    opacity: 1;
    box-shadow: 
        inset 0 0 90px rgba(255, 255, 255, 0.12),
        inset 0 -50px 70px rgba(0, 0, 0, 0.12),
        inset 40px 0 60px rgba(16, 185, 129, 0.15);
}

.book-cover-2 .book-pages-preview::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        url('data:image/svg+xml;utf8,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grain2" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="20" cy="20" r="1" fill="rgba(255,255,255,0.03)"/><circle cx="80" cy="80" r="1" fill="rgba(255,255,255,0.03)"/><circle cx="40" cy="60" r="0.5" fill="rgba(255,255,255,0.02)"/><circle cx="60" cy="30" r="0.5" fill="rgba(255,255,255,0.02)"/></pattern></defs><rect width="100" height="100" fill="url(%23grain2)"/></svg>'),
        repeating-linear-gradient(
            45deg,
            transparent,
            transparent 2px,
            rgba(255, 255, 255, 0.02) 2px,
            rgba(255, 255, 255, 0.02) 4px
        );
    z-index: 1;
    pointer-events: none;
    opacity: 0.5;
}

.book-cover-2 .book-spine-preview {
    background: linear-gradient(90deg, 
        rgba(5, 150, 105, 0.95) 0%,
        rgba(16, 185, 129, 0.9) 50%,
        rgba(5, 150, 105, 0.95) 100%);
    box-shadow: 
        inset -3px 0 10px rgba(0, 0, 0, 0.5),
        -3px 0 6px rgba(0, 0, 0, 0.3),
        inset 0 0 20px rgba(16, 185, 129, 0.2);
}

.book-cover-2 .book-pages-preview {
    justify-content: flex-start;
    padding-top: 3.5rem;
    align-items: flex-start;
}

.book-cover-2 .book-pages-preview h3,
.book-cover-2 .book-pages-preview p {
    text-align: left;
    padding-left: 2rem;
    padding-right: 1.5rem;
    position: relative;
    z-index: 3;
    font-family: 'Georgia', 'Times New Roman', serif;
}

.book-cover-2 .book-pages-preview h3 {
    color: #ffffff;
    text-shadow: 
        0 4px 14px rgba(0, 0, 0, 0.8),
        0 2px 8px rgba(0, 0, 0, 0.6),
        0 1px 4px rgba(0, 0, 0, 0.4),
        0 0 50px rgba(16, 185, 129, 0.5);
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    line-height: 1.3;
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.15), transparent);
    padding: 0.75rem 1.5rem 0.75rem 2rem;
    border-left: 4px solid rgba(255, 255, 255, 0.5);
    margin-left: 0.5rem;
    display: inline-block;
}

.book-cover-2 .book-pages-preview p {
    color: rgba(255, 255, 255, 0.95);
    text-shadow: 
        0 3px 10px rgba(0, 0, 0, 0.7),
        0 1px 5px rgba(0, 0, 0, 0.5),
        0 0 30px rgba(5, 150, 105, 0.4);
    font-weight: 500;
    letter-spacing: 0.5px;
    font-size: 0.9rem;
    margin-top: 0.5rem;
    padding-left: 2rem;
}

/* Book 3 - Education/AI Style - Advanced radial gradient, bottom-aligned text */
.book-cover-3 .book-pages-preview,
.book-pages-3 {
    background: 
        radial-gradient(ellipse at 30% 35%, rgba(59, 130, 246, 0.92) 0%, transparent 50%),
        radial-gradient(ellipse at 70% 65%, rgba(147, 51, 234, 0.88) 0%, transparent 50%),
        linear-gradient(180deg, rgba(59, 130, 246, 0.85), rgba(147, 51, 234, 0.9)),
        url('https://images.unsplash.com/photo-1509062522246-3755977927d7?w=400&q=80') center/cover;
    background-blend-mode: multiply, screen, multiply;
    position: relative;
    overflow: hidden;
}

.book-cover-3 .book-pages-preview::before {
    background: 
        radial-gradient(ellipse at top left, rgba(255, 255, 255, 0.25) 0%, transparent 50%),
        radial-gradient(ellipse at bottom right, rgba(147, 51, 234, 0.35) 0%, transparent 50%),
        radial-gradient(ellipse at center, rgba(59, 130, 246, 0.2) 0%, transparent 70%);
    opacity: 1;
    box-shadow: inset 0 0 100px rgba(59, 130, 246, 0.15);
}

.book-cover-3 .book-pages-preview::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        repeating-conic-gradient(
            from 0deg at 50% 50%,
            transparent 0deg,
            transparent 10deg,
            rgba(255, 255, 255, 0.04) 10deg,
            rgba(255, 255, 255, 0.04) 20deg
        );
    z-index: 1;
    pointer-events: none;
}

.book-cover-3 .book-pages-preview {
    justify-content: flex-end;
    padding-bottom: 3.5rem;
}

.book-cover-3 .book-pages-preview h3,
.book-cover-3 .book-pages-preview p {
    text-align: right;
    padding-right: 2rem;
    padding-left: 1rem;
    position: relative;
    z-index: 3;
    background: linear-gradient(270deg, rgba(255, 255, 255, 0.2), transparent);
    padding: 0.5rem 2rem 0.5rem 1.5rem;
    border-right: 3px solid rgba(255, 255, 255, 0.4);
    margin-right: 1rem;
}

.book-cover-3 .book-pages-preview h3 {
    text-shadow: 
        0 3px 12px rgba(0, 0, 0, 0.7),
        0 2px 6px rgba(0, 0, 0, 0.5),
        0 0 40px rgba(59, 130, 246, 0.4);
    color: #ffffff;
}

.book-cover-3 .book-pages-preview p {
    text-shadow: 
        0 2px 8px rgba(0, 0, 0, 0.6),
        0 1px 3px rgba(0, 0, 0, 0.4),
        0 0 20px rgba(147, 51, 234, 0.3);
    color: #ffffff;
}

.ebook-label {
    position: absolute;
    top: 15px;
    right: 15px;
    background: rgba(255, 255, 255, 0.9);
    color: var(--primary-color);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    z-index: 10;
}

.book-card-content {
    padding: 2rem;
}

.book-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 1rem;
    line-height: 1.3;
}

.book-description {
    color: var(--text-light);
    line-height: 1.7;
    margin-bottom: 1.5rem;
    font-size: 1rem;
}

.book-meta {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.book-category,
.book-pages,
.book-views,
.book-clicks {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background-color: var(--bg-light);
    border-radius: 20px;
    font-size: 0.875rem;
    color: var(--text-dark);
    font-weight: 500;
}

.book-category svg,
.book-pages svg,
.book-views svg,
.book-clicks svg {
    flex-shrink: 0;
}

.book-price-section {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.book-old-price {
    font-size: 1.25rem;
    color: var(--text-light);
    text-decoration: line-through;
}

.book-current-price {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

.book-discount {
    padding: 0.5rem 1rem;
    background-color: #fee2e2;
    color: #dc2626;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.875rem;
}

.btn-book {
    display: block;
    width: 100%;
    padding: 1rem 2rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    text-align: center;
    text-decoration: none;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1.125rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.25);
}

.btn-book:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
    transform: translateY(-2px);
    box-shadow: 0 8px 20px 0 rgba(99, 102, 241, 0.35);
    color: white;
}

.btn-book:active {
    transform: translateY(0);
}

/* Product Details Section */
.product-details-section {
    padding: 5rem 0;
    background-color: var(--bg-white);
    min-height: 80vh;
}

.btn-back {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background-color: var(--bg-light);
    color: var(--text-dark);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 2rem;
}

.btn-back:hover {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.product-details-wrapper {
    display: grid;
    grid-template-columns: 1fr 400px;
    gap: 3rem;
    align-items: start;
}

.product-details-left {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.product-details-right {
    position: sticky;
    top: 100px;
}

.product-image-gallery {
    width: 100%;
}

.product-main-image {
    width: 100%;
    background: linear-gradient(135deg, #f0f9ff 0%, #e0e7ff 100%);
    border-radius: 16px;
    padding: 2rem;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 400px;
    position: relative;
    margin-bottom: 1rem;
}

.product-main-image img {
    width: 100%;
    max-width: 600px;
    height: auto;
    border-radius: 12px;
    object-fit: contain;
    transition: opacity 0.3s ease;
}

.product-thumbnails {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    justify-content: center;
    margin-top: 1rem;
}

.product-thumbnail {
    width: 80px;
    height: 80px;
    border-radius: 8px;
    overflow: hidden;
    cursor: pointer;
    border: 2px solid transparent;
    transition: all 0.3s ease;
    background: var(--bg-white);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.product-thumbnail:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

.product-thumbnail.active {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

.product-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

@media (max-width: 768px) {
    .product-thumbnail {
        width: 60px;
        height: 60px;
    }
    
    .product-thumbnails {
        gap: 0.5rem;
    }

    .delivery-banner {
        padding: 0.625rem 0;
    }

    .delivery-banner-text {
        font-size: 0.8125rem;
        gap: 0.375rem;
    }

    .delivery-icon {
        font-size: 1rem;
    }
}

.product-details-image {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.product-details-image .book-cover-preview {
    width: 250px;
    height: 350px;
}

.product-info-card {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--shadow);
}

.product-details-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 1.5rem;
    line-height: 1.3;
}

.product-meta-info {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.product-meta-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.9375rem;
    color: var(--text-light);
}

.product-meta-item svg {
    flex-shrink: 0;
    color: var(--primary-color);
}

.product-meta-item strong {
    color: var(--text-dark);
    font-weight: 600;
}


.product-description-section {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
}

.section-heading {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 1.25rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--border-color);
}

.product-description-text {
    font-size: 1rem;
    color: var(--text-light);
    line-height: 1.8;
}

.product-description-text p {
    margin-bottom: 1rem;
    white-space: pre-line;
}

.product-description-text p:empty {
    display: none;
}

.product-features-section {
    margin-top: 2rem;
}

.product-features-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.product-features-section .product-features-list li {
    padding: 0.75rem 1rem;
    margin-bottom: 0.5rem;
    background-color: var(--bg-light);
    border-left: 4px solid var(--primary-color);
    border-radius: 4px;
    color: var(--text-dark);
    font-size: 1rem;
}

.product-specs-section {
    margin-top: 2rem;
}

.chapters-list {
    display: grid;
    gap: 1rem;
}

.chapter-item {
    padding: 1.25rem 1.5rem;
    background-color: var(--bg-light);
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
    color: var(--text-dark);
    font-size: 1rem;
    transition: transform 0.3s ease;
}

.chapter-item:hover {
    transform: translateX(5px);
}

.book-audience-section {
    padding: 5rem 0;
    background: linear-gradient(180deg, #f8fafc 0%, #f1f5f9 100%);
}

.book-audience-wrapper {
    max-width: 1200px;
    margin: 0 auto;
}

.book-audience-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 4rem;
    align-items: start;
}

.book-audience-header {
    position: sticky;
    top: 100px;
    padding-right: 2rem;
}

.book-audience-header h2 {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 1.25rem;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.book-audience-header p {
    font-size: 1.125rem;
    color: var(--text-light);
    margin-bottom: 2.5rem;
    line-height: 1.7;
}

.btn-audience-cta {
    display: inline-block;
    padding: 1.125rem 2.5rem;
    background-color: var(--primary-color);
    color: white;
    border-radius: 10px;
    font-size: 1.125rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
    width: 100%;
    text-align: center;
}

.btn-audience-cta:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}

.book-audience-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.audience-card {
    background: var(--bg-white);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
    display: flex;
    flex-direction: column;
}

.audience-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    border-color: var(--primary-color);
}

.audience-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.875rem;
    line-height: 1.3;
    letter-spacing: -0.01em;
}

.audience-card p {
    font-size: 1rem;
    color: var(--text-light);
    line-height: 1.6;
    margin: 0;
    flex-grow: 1;
}

.product-price-card {
    margin-top: 1.5rem;
}

.product-price-info {
    display: flex;
    align-items: baseline;
    gap: 1rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.product-current-price {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    letter-spacing: -0.02em;
}

.product-old-price {
    font-size: 1.25rem;
    color: var(--text-light);
    text-decoration: line-through;
    opacity: 0.7;
}

.product-discount-badge {
    padding: 0.375rem 0.75rem;
    background-color: #fee2e2;
    color: #dc2626;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.875rem;
}

.product-action-buttons {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.btn-product-primary,
.btn-product-secondary {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 1rem 1.5rem;
    font-size: 1.125rem;
    font-weight: 600;
    border-radius: 12px;
    text-decoration: none;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    width: 100%;
}

.btn-product-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.25);
}

.btn-product-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
    transform: translateY(-2px);
    box-shadow: 0 6px 20px 0 rgba(99, 102, 241, 0.35);
    color: white;
}

.btn-product-secondary {
    background-color: var(--bg-white);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

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

.product-delivery-info {
    margin-top: 1rem;
    font-size: 0.875rem;
    color: var(--text-light);
    text-align: center;
    line-height: 1.6;
    padding: 0.75rem;
    background-color: var(--bg-light);
    border-radius: 8px;
}

.btn-book-large {
    padding: 1.25rem 3rem;
    font-size: 1.25rem;
}

/* Blog Details Section */
.blog-details-section {
    padding: 5rem 0;
    background-color: var(--bg-white);
    min-height: 80vh;
}

.blog-details-wrapper {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 4rem;
    align-items: start;
}

.blog-details-image {
    position: sticky;
    top: 100px;
}

.blog-details-image img {
    width: 100%;
    height: auto;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
}

.blog-details-info {
    padding: 1rem 0;
}

.blog-details-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.blog-details-category {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

.blog-details-meta {
    display: flex;
    gap: 1rem;
    font-size: 0.875rem;
    color: var(--text-light);
}

.blog-details-date,
.blog-details-read-time {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.blog-details-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 2rem;
    line-height: 1.2;
}

.blog-details-content-text {
    font-size: 1.125rem;
    color: var(--text-dark);
    line-height: 1.8;
}

.blog-details-content-text p {
    margin-bottom: 1.5rem;
}

.blog-details-content-text ul {
    list-style: none;
    padding: 0;
    margin: 1.5rem 0;
}

.blog-details-content-text li {
    padding: 0.75rem 0;
    padding-left: 1.5rem;
    position: relative;
    color: var(--text-dark);
}

.blog-details-content-text li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
    font-size: 1.5rem;
}

/* Blogs Section */
.blogs-section {
    padding: 5rem 0;
    background-color: var(--bg-light);
}

.blogs-section .section-title {
    text-align: left;
    margin-bottom: 3rem;
}

.blogs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 2rem;
}

.blog-card {
    background-color: var(--bg-white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.blog-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.blog-image {
    position: relative;
    width: 100%;
    height: 200px;
    overflow: hidden;
}

.blog-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.blog-card:hover .blog-image img {
    transform: scale(1.05);
}

.blog-category {
    position: absolute;
    top: 1rem;
    left: 1rem;
    background-color: var(--primary-color);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

.blog-content {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.blog-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--text-dark);
    line-height: 1.4;
}

.blog-excerpt {
    color: var(--text-light);
    font-size: 0.9375rem;
    line-height: 1.6;
    margin-bottom: 1rem;
    flex-grow: 1;
}

.blog-meta {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: var(--text-light);
}

.blog-date,
.blog-read-time {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-blog {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 500;
    transition: all 0.3s ease;
    text-align: center;
    width: 100%;
}

.btn-blog:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

/* About Section */
.about-section {
    padding: 5rem 0;
    background-color: var(--bg-light);
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-text {
    font-size: 1.125rem;
    color: var(--text-light);
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

.about-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.about-feature {
    padding: 2rem;
    background-color: var(--bg-white);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.about-feature:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
    border-color: var(--primary-color);
}

.about-feature h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 0.75rem;
}

.about-feature p {
    color: var(--text-light);
    line-height: 1.6;
    margin: 0;
}

/* Footer Section */
.footer {
    background-color: var(--text-dark);
    color: white;
    padding: 2rem 0;
    margin-top: 0;
}

.footer-bottom {
    text-align: center;
    color: #9ca3af;
}

.footer-bottom p {
    margin: 0;
}

/* Responsive Design */
@media (max-width: 968px) {
    .hero-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .hero-image {
        display: none;
    }

    .books-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

    .book-card-image {
        min-height: 250px;
        padding: 2rem 1.5rem;
    }

    .book-cover-preview {
        width: 160px;
        height: 224px;
    }

    .product-details-wrapper {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .product-details-right {
        position: relative;
        top: 0;
    }

    .blog-details-wrapper {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .blog-details-image {
        position: relative;
        top: 0;
    }

    .blog-details-title {
        font-size: 2rem;
    }

    .product-details-image {
        position: relative;
        top: 0;
    }

    .product-details-image .book-cover-preview {
        width: 200px;
        height: 280px;
    }

    .product-details-title {
        font-size: 2rem;
    }

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

    .target-audience {
        grid-template-columns: repeat(2, 1fr);
    }

    .cta-content {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }

    .cta-content h2 {
        font-size: 2rem;
    }

    .cta-method-card {
        padding: 1.75rem 1.5rem;
    }

    .method-icon {
        font-size: 2rem;
    }

    .method-current-price {
        font-size: 1.5rem;
    }

    .cta-current-price {
        font-size: 2.5rem;
    }

    .buy-now-content {
        grid-template-columns: 1fr;
        gap: 2.5rem;
    }

    .buy-now-section {
        padding: 3rem 0;
    }

    .price-display .current-price {
        font-size: 2.5rem;
    }

    .btn-main-cta {
        width: 100%;
        font-size: 1.125rem;
        padding: 1.125rem 2.5rem;
    }

    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--bg-white);
        width: 100%;
        text-align: center;
        transition: left 0.3s ease;
        box-shadow: var(--shadow-lg);
        padding: 2rem 0;
        gap: 1rem;
    }

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

    .btn-menu-toggle {
        display: flex;
    }

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

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

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

    .hero {
        padding: 3rem 0;
        min-height: auto;
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .books-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .book-card-image {
        min-height: 250px;
        padding: 2rem 1.5rem;
    }

    .book-cover-preview {
        width: 160px;
        height: 224px;
    }

    .hero-image {
        display: none;
    }

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

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

    .hero-features {
        gap: 1.5rem;
    }

    .books-showcase {
        height: 300px;
    }

    .book-stack {
        width: 250px;
        height: 300px;
    }

    .book-item {
        width: 150px;
        height: 210px;
    }

    .book-2 {
        left: 40px;
    }

    .book-3 {
        left: 80px;
    }

    .product-details-title {
        font-size: 1.75rem;
    }

    .product-details-image .book-cover-preview {
        width: 180px;
        height: 252px;
    }

    .product-details-description p {
        font-size: 1rem;
    }

    .subheadline {
        font-size: 1.1rem;
    }

    .section-title {
        font-size: 1.75rem;
        margin-bottom: 2rem;
    }

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

    .microcopy {
        font-size: 0.95rem;
    }

    .buy-now-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .buy-now-section {
        padding: 2.5rem 0;
    }

    .price-display .current-price {
        font-size: 2.25rem;
    }

    .btn-main-cta {
        width: 100%;
        font-size: 1.125rem;
        padding: 1.125rem 2rem;
    }

    .cta-section {
        padding: 3rem 0;
    }

    .cta-content {
        grid-template-columns: 1fr;
        gap: 1.5rem;
        text-align: center;
    }

    .cta-content h2 {
        font-size: 1.75rem;
    }

    .cta-content > .cta-column > p {
        font-size: 1.1rem;
    }

    .cta-current-price {
        font-size: 2.25rem;
    }

    .cta-method-card {
        padding: 1.5rem 1.25rem;
    }

    .method-icon {
        font-size: 2rem;
        margin-bottom: 0.875rem;
    }

    .cta-method-card h3 {
        font-size: 1.125rem;
        margin-bottom: 1.25rem;
    }

    .method-current-price {
        font-size: 1.5rem;
    }

    .method-old-price {
        font-size: 0.9375rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .btn-primary,
    .btn-secondary {
        width: 100%;
        min-width: unset;
    }

    .details-tabs {
        flex-direction: column;
        border-bottom: none;
    }

    .tab-btn {
        border-bottom: none;
        border-left: 3px solid transparent;
        text-align: left;
        margin-bottom: 0;
    }

    .tab-btn.active {
        border-left-color: var(--primary-color);
        border-bottom-color: transparent;
    }

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

    .book-audience-section {
        padding: 3rem 0;
    }

    .book-audience-content {
        grid-template-columns: 1fr;
        gap: 2.5rem;
    }

    .book-audience-header {
        position: static;
        text-align: center;
        padding-right: 0;
    }

    .book-audience-header h2 {
        font-size: 1.875rem;
        margin-bottom: 1rem;
    }

    .book-audience-header p {
        font-size: 1.0625rem;
        margin-bottom: 2rem;
    }

    .btn-audience-cta {
        width: 100%;
        text-align: center;
        padding: 1rem 2rem;
    }

    .book-audience-cards {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }

    .audience-card {
        padding: 1.75rem;
        border-radius: 10px;
    }

    .audience-card h3 {
        font-size: 1.125rem;
        margin-bottom: 0.75rem;
    }

    .audience-card p {
        font-size: 0.9375rem;
    }

}

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

    .logo h1 {
        font-size: 1.5rem;
    }

    .hero {
        padding: 2rem 0;
    }

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

    .hero-subtitle {
        font-size: 1rem;
    }

    .book-cover-preview {
        width: 140px;
        height: 196px;
    }

    .book-card-image {
        min-height: 220px;
        padding: 1.5rem 1rem;
    }

    .book-title {
        font-size: 1.125rem;
    }

    .book-current-price {
        font-size: 1.5rem;
    }

    .hero-features {
        flex-direction: column;
        gap: 1rem;
    }

    .books-showcase {
        height: 250px;
    }

    .book-stack {
        width: 200px;
        height: 250px;
    }

    .book-item {
        width: 120px;
        height: 168px;
    }

    .book-2 {
        left: 30px;
    }

    .book-3 {
        left: 60px;
    }

    .section-title {
        font-size: 1.5rem;
        margin-bottom: 1.5rem;
    }

    .audience-card {
        padding: 1.5rem;
    }

    .audience-icon {
        font-size: 2.5rem;
    }

    .audience-card h3 {
        font-size: 1.25rem;
    }

    .microcopy {
        font-size: 0.9rem;
    }

    .btn-primary {
        min-width: 100%;
    }

    .cta-content {
        grid-template-columns: 1fr;
        gap: 1.5rem;
        text-align: center;
    }

    .cta-content h2 {
        font-size: 1.5rem;
    }

    .cta-content > .cta-column > p {
        font-size: 1rem;
    }

    .cta-old-price {
        font-size: 1.125rem;
    }

    .cta-current-price {
        font-size: 2rem;
    }

    .cta-method-card {
        padding: 1.5rem 1.25rem;
    }

    .method-icon {
        font-size: 1.75rem;
        margin-bottom: 0.75rem;
    }

    .cta-method-card h3 {
        font-size: 1.125rem;
        margin-bottom: 1rem;
    }

    .method-price {
        padding: 0.625rem;
        margin-bottom: 1.25rem;
    }

    .method-current-price {
        font-size: 1.375rem;
    }

    .method-old-price {
        font-size: 0.875rem;
    }

    .btn-cta-method {
        font-size: 0.9375rem;
        padding: 0.75rem 1.25rem;
    }

    .buy-now-content {
        gap: 2rem;
    }

    .buy-now-section {
        padding: 2rem 0;
    }

    .buy-now-subtitle {
        font-size: 1rem;
        margin-bottom: 2rem;
    }

    .price-display .current-price {
        font-size: 2rem;
    }

    .price-display .old-price {
        font-size: 1.25rem;
    }

    .btn-main-cta {
        font-size: 1rem;
        padding: 1rem 2rem;
    }

    .tab-content h2 {
        font-size: 1.5rem;
    }

    .tab-content h3 {
        font-size: 1.25rem;
    }

    .price-section {
        flex-direction: column;
        align-items: flex-start;
    }
}

/* Similar Products Section */
.similar-products-section {
    margin-top: 4rem;
    padding-top: 3rem;
    border-top: 2px solid var(--border-color);
}

.similar-products-heading {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 2rem;
    text-align: center;
}

.similar-products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 3rem;
    max-width: 1200px;
    margin: 0 auto;
    justify-items: center;
}

/* Similar products use the same styles as book-card */
.similar-products-grid .book-card {
    max-width: 400px;
    width: 100%;
}

/* Responsive Styles for Similar Products */
@media (max-width: 768px) {
    .similar-products-section {
        margin-top: 3rem;
        padding-top: 2rem;
    }

    .similar-products-heading {
        font-size: 1.5rem;
        margin-bottom: 1.5rem;
    }

    .similar-products-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
}