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

:root {
    --primary-green: #4ADE80;
    --dark-green: #16A34A;
    --light-green: #86EFAC;
    --primary-blue: #60A5FA;
    --dark-blue: #3B82F6;
    --light-blue: #BFDBFE;
    --black: #000000;
    --white: #FFFFFF;
    --gray-50: #F9FAFB;
    --gray-100: #F3F4F6;
    --gray-200: #E5E7EB;
    --gray-300: #D1D5DB;
    --gray-600: #4B5563;
    --gray-800: #1F2937;
    --gray-900: #111827;
    
    --font-family: 'Inter', sans-serif;
    --border-radius: 12px;
    --border-radius-lg: 20px;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
}

body {
    font-family: var(--font-family);
    line-height: 1.6;
    color: var(--gray-800);
    background-color: var(--white);
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--gray-900);
}

.highlight-green {
    color: var(--primary-green);
    font-weight: 800;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border: 2px solid transparent;
    border-radius: var(--border-radius);
    font-family: var(--font-family);
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.2s ease;
    text-align: center;
    justify-content: center;
}

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

.btn-primary:hover {
    background-color: var(--dark-green);
    border-color: var(--dark-green);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-outline {
    background-color: transparent;
    color: var(--primary-blue);
    border-color: var(--primary-blue);
}

.btn-outline:hover {
    background-color: var(--light-blue);
    color: var(--dark-blue);
    border-color: var(--light-blue);
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(191, 219, 254, 0.4);
}

.btn-large {
    padding: 16px 32px;
    font-size: 18px;
}

.btn-full {
    width: 100%;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--gray-200);
    z-index: 1000;
}

.nav {
    padding: 16px 0;
}

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

/* Brand Hierarchy */
.brand-hierarchy {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.brand-name {
    font-size: 16px;
    font-weight: 700;
    color: var(--gray-600);
    letter-spacing: 1px;
    line-height: 1;
}

.product-name {
    font-size: 18px;
    font-weight: 900;
    color: var(--black);
    letter-spacing: -0.5px;
    line-height: 1.1;
    margin-top: 2px;
}

.nav-buttons {
    display: flex;
    gap: 12px;
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, var(--gray-50) 0%, var(--white) 100%);
}

/* Product Badge */
.product-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 24px;
    padding: 8px 20px;
    background-color: var(--white);
    border: 2px solid var(--primary-green);
    border-radius: 50px;
    box-shadow: var(--shadow-sm);
}

.badge-brand {
    font-size: 12px;
    font-weight: 700;
    color: var(--primary-green);
    letter-spacing: 1px;
}

.badge-presents {
    font-size: 10px;
    font-weight: 500;
    color: var(--gray-500);
    letter-spacing: 0.5px;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    min-height: 600px;
}

.hero-title {
    font-size: 4rem;
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 24px;
    color: var(--black);
    letter-spacing: -2px;
}

.hero-subtitle {
    font-size: 24px;
    color: var(--gray-700);
    margin-bottom: 16px;
    font-weight: 600;
}

.hero-description {
    font-size: 18px;
    color: var(--gray-600);
    margin-bottom: 40px;
    font-weight: 400;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

/* Book Cover */
.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.book-cover {
    position: relative;
    width: 300px;
    height: 400px;
    perspective: 1000px;
    transform: rotateY(-15deg) rotateX(5deg);
    transition: transform 0.3s ease;
}

.book-cover:hover {
    transform: rotateY(-10deg) rotateX(2deg) scale(1.05);
}

.book-spine {
    position: absolute;
    left: -20px;
    top: 0;
    width: 20px;
    height: 100%;
    background: linear-gradient(180deg, var(--gray-400) 0%, var(--gray-500) 100%);
    transform: rotateY(-90deg);
    transform-origin: right;
}

.book-front {
    width: 100%;
    height: 100%;
    position: relative;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow-xl);
}

.book-cover-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.book-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.book-front:hover .book-overlay {
    opacity: 1;
}

.book-hover-text {
    text-align: center;
    color: var(--white);
}

.hover-label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--light-blue);
    text-shadow: 0 0 10px rgba(191, 219, 254, 0.5);
}

.hover-content {
    display: block;
    font-size: 16px;
    font-weight: 700;
    line-height: 1.3;
}



/* About Section */
.about {
    padding: 80px 0;
    background-color: var(--white);
}

.about h2 {
    font-size: 3rem;
    text-align: center;
    margin-bottom: 60px;
    color: var(--black);
}

.about-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 60px;
    align-items: start;
}

.about-text h3 {
    font-size: 2rem;
    margin-bottom: 24px;
    color: var(--primary-green);
}

.about-text p {
    font-size: 18px;
    line-height: 1.7;
    margin-bottom: 24px;
    color: var(--gray-600);
}

.features {
    margin-top: 40px;
}

.feature {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
    padding: 20px;
    background-color: var(--gray-50);
    border-radius: var(--border-radius);
    border-left: 4px solid var(--primary-green);
}

.feature i {
    font-size: 24px;
    color: var(--primary-green);
    margin-top: 4px;
}

.feature h4 {
    font-size: 18px;
    margin-bottom: 8px;
    color: var(--gray-900);
}

.feature p {
    font-size: 16px;
    color: var(--gray-600);
    margin: 0;
}

/* Kit Contents */
.kit-contents {
    margin-top: 40px;
    padding: 32px;
    background-color: var(--white);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
}

.kit-contents h4 {
    font-size: 20px;
    color: var(--gray-900);
    margin-bottom: 24px;
    text-align: center;
}

.contents-list {
    display: grid;
    gap: 20px;
}

.content-item {
    display: flex;
    gap: 16px;
    align-items: flex-start;
    padding: 16px;
    background-color: var(--gray-50);
    border-radius: var(--border-radius);
    border-left: 4px solid var(--primary-green);
}

.content-item i {
    font-size: 20px;
    color: var(--primary-green);
    margin-top: 4px;
    flex-shrink: 0;
}

.content-item:nth-child(2) i {
    color: var(--primary-blue);
}

.content-item:nth-child(2) {
    border-left-color: var(--primary-blue);
}

.content-item strong {
    display: block;
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: 4px;
}

.content-item p {
    font-size: 14px;
    color: var(--gray-600);
    margin: 0;
    line-height: 1.4;
}

.about-stats {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.stat {
    text-align: center;
    padding: 32px 24px;
    background: linear-gradient(135deg, var(--primary-green) 0%, var(--dark-green) 100%);
    border-radius: var(--border-radius-lg);
    color: var(--white);
}

.stat:nth-child(2) {
    background: linear-gradient(135deg, var(--light-blue) 0%, var(--primary-blue) 100%);
}

.stat-number {
    display: block;
    font-size: 3rem;
    font-weight: 900;
    line-height: 1;
    margin-bottom: 8px;
}

.stat-label {
    font-size: 16px;
    font-weight: 500;
    opacity: 0.9;
}

/* Purchase Section */
.purchase {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--gray-50) 0%, var(--white) 100%);
}

.purchase h2 {
    font-size: 3rem;
    text-align: center;
    margin-bottom: 16px;
    color: var(--black);
}

.purchase-subtitle {
    font-size: 20px;
    text-align: center;
    color: var(--gray-600);
    margin-bottom: 60px;
}

.purchase-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}

.price-card {
    background-color: var(--white);
    padding: 40px;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-lg);
    text-align: center;
    margin-bottom: 32px;
    border: 2px solid var(--primary-green);
}

.price {
    display: flex;
    align-items: baseline;
    justify-content: center;
    margin-bottom: 16px;
}

.currency {
    font-size: 24px;
    font-weight: 600;
    color: var(--gray-600);
}

.amount {
    font-size: 4rem;
    font-weight: 900;
    color: var(--primary-green);
    line-height: 1;
}

.period {
    font-size: 24px;
    font-weight: 600;
    color: var(--gray-600);
}

.price-description {
    color: var(--gray-600);
    font-size: 16px;
}

.guarantee {
    display: flex;
    gap: 16px;
    padding: 24px;
    background-color: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
}

.guarantee i {
    font-size: 24px;
    color: var(--primary-green);
    margin-top: 4px;
}

.guarantee h4 {
    font-size: 18px;
    margin-bottom: 8px;
    color: var(--gray-900);
}

.guarantee p {
    color: var(--gray-600);
    margin: 0;
}

/* Payment Form */
.payment-form {
    background-color: var(--white);
    padding: 40px;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-lg);
}

.payment-form h3 {
    font-size: 24px;
    margin-bottom: 32px;
    color: var(--gray-900);
    text-align: center;
}

.form-group {
    margin-bottom: 24px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 8px;
}

.form-group input {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--gray-200);
    border-radius: var(--border-radius);
    font-size: 16px;
    font-family: var(--font-family);
    transition: border-color 0.2s ease;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-green);
    box-shadow: 0 0 0 3px rgba(74, 222, 128, 0.1);
}

.form-group small {
    display: block;
    font-size: 12px;
    color: var(--gray-500);
    margin-top: 4px;
}

.security-note {
    text-align: center;
    font-size: 14px;
    color: var(--gray-500);
    margin-top: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.security-note i {
    color: var(--primary-green);
}

/* Footer */
.footer {
    background-color: var(--gray-900);
    color: var(--white);
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    margin-bottom: 40px;
}

.footer-brand h3 {
    font-size: 24px;
    margin-bottom: 16px;
    color: var(--white);
}

.footer-brand p {
    color: var(--gray-300);
    font-size: 16px;
}

.footer-links {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.footer-section h4 {
    font-size: 18px;
    margin-bottom: 16px;
    color: var(--white);
}

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

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

.footer-section a {
    color: var(--gray-300);
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-section a:hover {
    color: var(--primary-green);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid var(--gray-700);
    color: var(--gray-400);
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.8);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.loading-overlay.active {
    display: flex;
}

.loading-spinner {
    text-align: center;
    color: var(--white);
}

.loading-spinner i {
    font-size: 48px;
    color: var(--primary-green);
    margin-bottom: 16px;
}

.loading-spinner p {
    font-size: 18px;
    font-weight: 500;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    .brand-hierarchy {
        align-items: center;
        text-align: center;
    }
    
    .brand-name {
        font-size: 14px;
    }
    
    .product-name {
        font-size: 16px;
    }
    
    .nav-buttons {
        flex-direction: column;
        gap: 8px;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .book-cover {
        width: 250px;
        height: 350px;
        transform: none;
    }
    
    .about h2 {
        font-size: 2rem;
    }
    
    .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .about-stats {
        flex-direction: row;
        justify-content: space-around;
    }
    
    .purchase h2 {
        font-size: 2rem;
    }
    
    .purchase-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .form-row {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }
    
    .footer-links {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .kit-contents {
        padding: 24px;
    }
    
    .content-item {
        flex-direction: column;
        text-align: center;
        gap: 12px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .book-cover {
        width: 200px;
        height: 280px;
    }
    
    .hover-label {
        font-size: 12px;
    }
    
    .hover-content {
        font-size: 14px;
    }
    
    .hero-buttons {
        flex-direction: column;
        width: 100%;
    }
    
    .btn {
        width: 100%;
    }
    
    .payment-form {
        padding: 24px;
    }
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-content,
.about-content,
.purchase-content {
    animation: fadeInUp 0.8s ease-out;
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Focus states for accessibility */
.btn:focus,
input:focus {
    outline: 2px solid var(--primary-green);
    outline-offset: 2px;
}

/* Print styles */
@media print {
    .header,
    .footer,
    .purchase {
        display: none;
    }
}