:root {
    --color-dark-green: #1a4d2e;
    --color-forest-green: #2d6a4f;
    --color-mid-green: #40916c;
    --color-light-green: #52b788;
    --color-accent-green: #74c69d;
    --color-white: #ffffff;
    --color-light-gray: #f8f9fa;
    --color-gray: #6c757d;
    --color-dark-gray: #343a40;
    --color-text: #212529;
    --color-black: #000000;
    
    --gradient-primary: linear-gradient(135deg, var(--color-dark-green) 0%, var(--color-forest-green) 50%, var(--color-mid-green) 100%);
    --gradient-secondary: linear-gradient(135deg, var(--color-forest-green) 0%, var(--color-mid-green) 100%);
    --gradient-accent: linear-gradient(135deg, var(--color-mid-green) 0%, var(--color-light-green) 50%, var(--color-accent-green) 100%);
    --gradient-overlay: linear-gradient(180deg, rgba(26, 77, 46, 0.02) 0%, rgba(255, 255, 255, 0) 100%);
    
    --font-serif: 'Crimson Pro', serif;
    --font-sans: 'Inter', sans-serif;
    
    --transition-smooth: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: all 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
    
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07), 0 2px 4px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1), 0 4px 6px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1), 0 10px 10px rgba(0, 0, 0, 0.04);
    --shadow-2xl: 0 25px 50px rgba(0, 0, 0, 0.15), 0 10px 20px rgba(0, 0, 0, 0.08);
    --shadow-green: 0 10px 30px rgba(26, 77, 46, 0.2);
    
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    --border-radius-sm: 0.375rem;
    --border-radius-md: 0.5rem;
    --border-radius-lg: 0.75rem;
    --border-radius-xl: 1rem;
    --border-radius-2xl: 1.5rem;
    --border-radius-full: 9999px;
    
    --max-width-sm: 640px;
    --max-width-md: 768px;
    --max-width-lg: 1024px;
    --max-width-xl: 1280px;
    --max-width-2xl: 1536px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    -webkit-tap-highlight-color: transparent;
}

@media (max-width: 768px) {
    html {
        font-size: 15px;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }
}

body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background-color: var(--color-white);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
    min-height: 100vh;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
    user-select: none;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-smooth);
}

a:focus-visible {
    outline: 2px solid var(--color-forest-green);
    outline-offset: 4px;
    border-radius: var(--border-radius-sm);
}

ul {
    list-style: none;
}

button {
    border: none;
    background: none;
    cursor: pointer;
    font-family: inherit;
    touch-action: manipulation;
}

button:focus-visible {
    outline: 2px solid var(--color-forest-green);
    outline-offset: 4px;
}

button:disabled {
    cursor: not-allowed;
}

.container {
    max-width: var(--max-width-xl);
    margin: 0 auto;
    padding: 0 clamp(1rem, 5vw, 2rem);
    width: 100%;
}

@media (min-width: 1536px) {
    .container {
        max-width: var(--max-width-2xl);
    }
}

.demo-popup {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10000;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    animation: fadeIn 0.3s ease-out;
    padding: var(--spacing-lg);
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.demo-popup-content {
    background: var(--color-white);
    padding: clamp(2rem, 5vw, 3rem);
    border-radius: var(--border-radius-xl);
    max-width: 540px;
    width: 100%;
    text-align: center;
    box-shadow: var(--shadow-2xl);
    animation: popupSlide 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
    position: relative;
}

@keyframes popupSlide {
    from {
        opacity: 0;
        transform: translateY(-30px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.demo-popup-content h2 {
    font-family: var(--font-serif);
    font-size: clamp(1.5rem, 4vw, 2rem);
    margin-bottom: var(--spacing-lg);
    color: var(--color-dark-green);
    line-height: 1.3;
}

.demo-popup-content p {
    margin-bottom: var(--spacing-md);
    color: var(--color-gray);
    font-size: clamp(0.95rem, 2vw, 1.0625rem);
    line-height: 1.7;
}

.demo-popup-content a {
    color: var(--color-forest-green);
    font-weight: 600;
    position: relative;
    display: inline-block;
}

.demo-popup-content a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transform-origin: right;
    transition: transform 0.3s ease;
}

.demo-popup-content a:hover::after {
    transform: scaleX(1);
    transform-origin: left;
}

.popup-btn {
    background: var(--gradient-primary);
    color: var(--color-white);
    padding: clamp(0.75rem, 2vw, 1rem) clamp(1.5rem, 4vw, 2.5rem);
    border-radius: var(--border-radius-lg);
    font-weight: 600;
    font-size: clamp(0.95rem, 2vw, 1.0625rem);
    margin-top: var(--spacing-lg);
    transition: var(--transition-smooth);
    cursor: pointer;
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
}

.popup-btn::before {
    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, height 0.6s;
}

.popup-btn:hover::before {
    width: 300px;
    height: 300px;
}

.popup-btn:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.popup-btn:active {
    transform: translateY(-1px);
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: var(--transition-smooth);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
    background: rgba(255, 255, 255, 0.95);
}

.nav {
    padding: clamp(0.75rem, 2vw, 1rem) 0;
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--spacing-lg);
}

.logo {
    font-family: var(--font-serif);
    font-size: clamp(1.5rem, 3vw, 2rem);
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    transition: var(--transition-smooth);
    position: relative;
    display: inline-block;
}

.logo::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 3px;
    background: var(--gradient-primary);
    transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border-radius: var(--border-radius-full);
}

.logo:hover::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: var(--spacing-sm);
    background: transparent;
    border: none;
    z-index: 1001;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: var(--color-dark-green);
    border-radius: var(--border-radius-full);
    transition: var(--transition-smooth);
    transform-origin: center;
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translateY(8px);
}

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

.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translateY(-8px);
}

.nav-menu {
    display: flex;
    gap: clamp(1.25rem, 3vw, 2rem);
    align-items: center;
}

.nav-menu a {
    color: var(--color-text);
    font-weight: 500;
    font-size: clamp(0.9rem, 2vw, 1rem);
    position: relative;
    padding: var(--spacing-sm) 0;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: var(--transition-smooth);
    transform: translateX(-50%);
    border-radius: var(--border-radius-full);
}

.nav-menu a:hover::after,
.nav-menu a:focus::after {
    width: 100%;
}

.nav-cta {
    background: var(--gradient-primary);
    color: var(--color-white) !important;
    padding: clamp(0.5rem, 1.5vw, 0.625rem) clamp(1rem, 3vw, 1.5rem) !important;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
}

.nav-cta::after {
    display: none !important;
}

.nav-cta::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.5s, height 0.5s;
}

.nav-cta:hover::before {
    width: 300px;
    height: 300px;
}

.nav-cta:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.nav-cta:active {
    transform: translateY(0);
}

.hero {
    padding: clamp(7rem, 15vw, 9rem) 0 clamp(4rem, 8vw, 6rem);
    background: linear-gradient(to bottom, var(--color-light-gray) 0%, var(--color-white) 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 80%;
    height: 150%;
    background: radial-gradient(circle, rgba(26, 77, 46, 0.03) 0%, transparent 70%);
    pointer-events: none;
}

.hero-content {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: clamp(2rem, 6vw, 4rem);
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-text {
    animation: fadeInUp 0.8s ease-out;
}

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

.hero-title {
    font-family: var(--font-serif);
    font-size: clamp(2.25rem, 6vw, 4rem);
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
    color: var(--color-dark-green);
    line-height: 1.15;
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: clamp(1.125rem, 3vw, 1.75rem);
    color: var(--color-forest-green);
    margin-bottom: var(--spacing-xl);
    font-weight: 300;
    line-height: 1.4;
}

.hero-description {
    font-size: clamp(1rem, 2vw, 1.125rem);
    color: var(--color-gray);
    margin-bottom: var(--spacing-2xl);
    line-height: 1.8;
    max-width: 90%;
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: clamp(0.75rem, 2vw, 1rem) clamp(1.5rem, 4vw, 2.5rem);
    border-radius: var(--border-radius-lg);
    font-weight: 600;
    font-size: clamp(0.95rem, 2vw, 1.0625rem);
    transition: var(--transition-smooth);
    text-align: center;
    position: relative;
    overflow: hidden;
    white-space: nowrap;
}

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

.btn:hover::after {
    width: 400px;
    height: 400px;
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--color-white);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-3px);
    box-shadow: var(--shadow-green);
}

.btn-primary:active:not(:disabled) {
    transform: translateY(-1px);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-secondary {
    background: var(--color-white);
    color: var(--color-dark-green);
    border: 2px solid var(--color-dark-green);
    box-shadow: var(--shadow-sm);
}

.btn-secondary::after {
    background: var(--color-dark-green);
    opacity: 0.05;
}

.btn-secondary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--color-forest-green);
}

.btn-secondary:active {
    transform: translateY(-1px);
}

.btn-large {
    padding: clamp(1rem, 2.5vw, 1.25rem) clamp(2rem, 5vw, 3.5rem);
    font-size: clamp(1rem, 2.5vw, 1.25rem);
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: fadeInRight 0.8s ease-out 0.2s both;
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.hero-image img {
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-2xl);
    transition: var(--transition-smooth);
    width: 100%;
    max-width: 450px;
    height: auto;
}

.hero-image img:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 30px 60px rgba(26, 77, 46, 0.25);
}

.section-header {
    text-align: center;
    margin-bottom: clamp(2.5rem, 6vw, 4rem);
}

.section-header h2 {
    font-family: var(--font-serif);
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 700;
    color: var(--color-dark-green);
    margin-bottom: var(--spacing-lg);
    line-height: 1.2;
    letter-spacing: -0.01em;
}

.section-divider {
    width: 100px;
    height: 5px;
    background: var(--gradient-primary);
    margin: 0 auto;
    border-radius: var(--border-radius-full);
}

.about-book {
    padding: clamp(4rem, 10vw, 7rem) 0;
}

.about-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: clamp(2.5rem, 6vw, 4rem);
    align-items: start;
}

.about-text .lead {
    font-size: clamp(1.125rem, 3vw, 1.5rem);
    font-weight: 300;
    color: var(--color-dark-green);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
}

.about-text p {
    margin-bottom: var(--spacing-xl);
    font-size: clamp(0.95rem, 2vw, 1.0625rem);
    color: var(--color-text);
    line-height: 1.9;
}

.about-features {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
    position: sticky;
    top: 100px;
}

.feature-card {
    background: var(--color-white);
    padding: clamp(1.25rem, 3vw, 2rem);
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-md);
    transition: var(--transition-smooth);
    border-left: 4px solid transparent;
    position: relative;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-overlay);
    border-radius: var(--border-radius-xl);
    opacity: 0;
    transition: var(--transition-smooth);
    pointer-events: none;
}

.feature-card:hover::before {
    opacity: 1;
}

.feature-card:hover {
    transform: translateX(8px) translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-left-color: var(--color-forest-green);
}

.feature-icon {
    margin-bottom: var(--spacing-md);
    display: inline-flex;
    padding: var(--spacing-md);
    background: linear-gradient(135deg, rgba(26, 77, 46, 0.08) 0%, rgba(64, 145, 108, 0.08) 100%);
    border-radius: var(--border-radius-lg);
    transition: var(--transition-smooth);
}

.feature-card:hover .feature-icon {
    transform: scale(1.1) rotate(5deg);
}

.feature-icon svg {
    width: clamp(2.5rem, 5vw, 3rem);
    height: clamp(2.5rem, 5vw, 3rem);
    display: block;
}

.feature-card h3 {
    font-family: var(--font-serif);
    font-size: clamp(1.125rem, 2.5vw, 1.375rem);
    color: var(--color-dark-green);
    margin-bottom: var(--spacing-sm);
    line-height: 1.4;
}

.feature-card p {
    color: var(--color-gray);
    font-size: clamp(0.9rem, 2vw, 1rem);
    line-height: 1.7;
    margin-bottom: 0;
}

.author {
    padding: clamp(4rem, 10vw, 7rem) 0;
    background: var(--color-light-gray);
    position: relative;
    overflow: hidden;
}

.author::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -20%;
    width: 80%;
    height: 150%;
    background: radial-gradient(circle, rgba(26, 77, 46, 0.03) 0%, transparent 70%);
    pointer-events: none;
}

.author-content {
    display: grid;
    grid-template-columns: clamp(250px, 30vw, 350px) 1fr;
    gap: clamp(2.5rem, 6vw, 5rem);
    align-items: start;
    position: relative;
    z-index: 1;
}

.author-image {
    width: 100%;
    max-width: 350px;
    position: relative;
}

.author-image::before {
    content: '';
    position: absolute;
    top: -10px;
    left: -10px;
    right: 10px;
    bottom: 10px;
    background: var(--gradient-primary);
    border-radius: 50%;
    opacity: 0.1;
    z-index: -1;
}

.author-image img {
    border-radius: 50%;
    box-shadow: var(--shadow-2xl);
    border: 6px solid var(--color-white);
    width: 100%;
    height: auto;
    aspect-ratio: 1;
    object-fit: cover;
    transition: var(--transition-smooth);
}

.author-image:hover img {
    transform: scale(1.05);
    box-shadow: 0 25px 50px rgba(26, 77, 46, 0.2);
}

.author-text .section-header {
    text-align: left;
    margin-bottom: var(--spacing-2xl);
}

.author-text .section-divider {
    margin: 0;
}

.author-text .lead {
    font-size: clamp(1.125rem, 3vw, 1.375rem);
    font-weight: 300;
    color: var(--color-forest-green);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
}

.author-text p {
    margin-bottom: var(--spacing-xl);
    font-size: clamp(0.95rem, 2vw, 1.0625rem);
    color: var(--color-text);
    line-height: 1.9;
}

.reviews {
    padding: clamp(4rem, 10vw, 7rem) 0;
}

.reviews-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 300px), 1fr));
    gap: clamp(1.5rem, 3vw, 2rem);
}

.review-card {
    background: var(--color-white);
    padding: clamp(1.5rem, 3vw, 2.5rem);
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-md);
    transition: var(--transition-smooth);
    border-top: 4px solid transparent;
    display: flex;
    flex-direction: column;
    position: relative;
    overflow: hidden;
}

.review-card::before {
    content: '"';
    position: absolute;
    top: 20px;
    right: 25px;
    font-size: 6rem;
    font-family: var(--font-serif);
    color: rgba(26, 77, 46, 0.05);
    line-height: 1;
    pointer-events: none;
}

.review-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-top-color: var(--color-forest-green);
}

.review-stars {
    margin-bottom: var(--spacing-lg);
}

.review-stars svg {
    width: 130px;
    height: 22px;
    display: block;
}

.review-text {
    color: var(--color-text);
    font-size: clamp(0.95rem, 2vw, 1.0625rem);
    line-height: 1.8;
    margin-bottom: var(--spacing-xl);
    font-style: italic;
    flex-grow: 1;
}

.review-author {
    color: var(--color-gray);
    font-size: clamp(0.875rem, 2vw, 0.9375rem);
    font-weight: 600;
    margin-top: auto;
    padding-top: var(--spacing-md);
    border-top: 1px solid rgba(0, 0, 0, 0.05);
}

.order {
    padding: clamp(4rem, 10vw, 7rem) 0;
    background: linear-gradient(135deg, rgba(26, 77, 46, 0.03) 0%, rgba(64, 145, 108, 0.03) 100%);
    position: relative;
    overflow: hidden;
}

.order::before {
    content: '';
    position: absolute;
    bottom: -50%;
    right: -20%;
    width: 80%;
    height: 150%;
    background: radial-gradient(circle, rgba(116, 198, 157, 0.05) 0%, transparent 70%);
    pointer-events: none;
}

.order-content {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: clamp(3rem, 8vw, 6rem);
    align-items: center;
    position: relative;
    z-index: 1;
}

.order-book {
    display: flex;
    justify-content: center;
    position: relative;
}

.order-book::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 120%;
    height: 120%;
    background: radial-gradient(circle, rgba(26, 77, 46, 0.1) 0%, transparent 70%);
    transform: translate(-50%, -50%);
    z-index: -1;
}

.order-book img {
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-2xl);
    width: 100%;
    max-width: 350px;
    height: auto;
    transition: var(--transition-smooth);
}

.order-book img:hover {
    transform: translateY(-10px) scale(1.05);
    box-shadow: 0 35px 70px rgba(26, 77, 46, 0.3);
}

.order-info h2 {
    font-family: var(--font-serif);
    font-size: clamp(2rem, 5vw, 3rem);
    color: var(--color-dark-green);
    margin-bottom: var(--spacing-xl);
    line-height: 1.2;
    letter-spacing: -0.01em;
}

.order-description {
    font-size: clamp(1rem, 2vw, 1.125rem);
    color: var(--color-gray);
    margin-bottom: var(--spacing-3xl);
    line-height: 1.8;
}

.order-formats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 160px), 1fr));
    gap: clamp(1rem, 3vw, 1.5rem);
    margin-bottom: var(--spacing-3xl);
}

.format-option {
    background: var(--color-white);
    padding: clamp(1.25rem, 3vw, 2rem);
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-md);
    text-align: center;
    transition: var(--transition-smooth);
    border: 2px solid transparent;
    position: relative;
    overflow: hidden;
}

.format-option::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-primary);
    opacity: 0;
    transition: var(--transition-smooth);
}

.format-option:hover::before {
    opacity: 0.05;
}

.format-option:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-5px);
    border-color: var(--color-accent-green);
}

.format-option h3 {
    font-family: var(--font-serif);
    font-size: clamp(1.125rem, 2.5vw, 1.375rem);
    color: var(--color-dark-green);
    margin-bottom: var(--spacing-md);
    position: relative;
    z-index: 1;
}

.format-price {
    font-size: clamp(1.75rem, 4vw, 2.25rem);
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: var(--spacing-md);
    display: block;
    position: relative;
    z-index: 1;
}

.format-details {
    color: var(--color-gray);
    font-size: clamp(0.85rem, 2vw, 0.9375rem);
    line-height: 1.6;
    position: relative;
    z-index: 1;
}

.order-note {
    margin-top: var(--spacing-xl);
    color: var(--color-gray);
    font-size: clamp(0.9rem, 2vw, 1rem);
    text-align: center;
    line-height: 1.7;
}

.footer {
    background: var(--color-dark-gray);
    color: var(--color-white);
    padding: clamp(3rem, 8vw, 5rem) 0 clamp(1.5rem, 3vw, 2rem);
    position: relative;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent 0%, rgba(255, 255, 255, 0.2) 50%, transparent 100%);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr repeat(2, 1fr);
    gap: clamp(2rem, 6vw, 4rem);
    margin-bottom: clamp(2rem, 5vw, 3rem);
}

.footer-brand h3 {
    font-family: var(--font-serif);
    font-size: clamp(1.5rem, 3vw, 2rem);
    margin-bottom: var(--spacing-lg);
    background: var(--gradient-accent);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.75);
    line-height: 1.7;
    font-size: clamp(0.9rem, 2vw, 1rem);
}

.footer-links h4,
.footer-contact h4 {
    font-family: var(--font-serif);
    font-size: clamp(1.125rem, 2.5vw, 1.25rem);
    margin-bottom: var(--spacing-lg);
    color: var(--color-accent-green);
}

.footer-links ul {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.footer-links a {
    color: rgba(255, 255, 255, 0.75);
    transition: var(--transition-smooth);
    display: inline-block;
    font-size: clamp(0.9rem, 2vw, 0.9375rem);
}

.footer-links a:hover {
    color: var(--color-white);
    padding-left: var(--spacing-sm);
    transform: translateX(5px);
}

.footer-contact p {
    color: rgba(255, 255, 255, 0.75);
    margin-bottom: var(--spacing-md);
    font-size: clamp(0.9rem, 2vw, 0.9375rem);
    line-height: 1.7;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: clamp(1.5rem, 3vw, 2rem);
    text-align: center;
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.5);
    font-size: clamp(0.85rem, 2vw, 0.9375rem);
    margin-bottom: var(--spacing-sm);
}

.demo-notice {
    font-size: clamp(0.8rem, 2vw, 0.875rem);
}

.demo-notice a {
    color: var(--color-accent-green);
    font-weight: 600;
    position: relative;
}

.demo-notice a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--color-accent-green);
    transition: width 0.3s ease;
}

.demo-notice a:hover::after {
    width: 100%;
}

.demo-notice a:hover {
    color: var(--color-light-green);
}

@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        gap: clamp(2rem, 5vw, 3rem);
    }
    
    .hero-image {
        order: -1;
    }
    
    .about-content {
        grid-template-columns: 1fr;
    }
    
    .about-features {
        position: static;
    }
    
    .author-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: clamp(2rem, 5vw, 3rem);
    }
    
    .author-image {
        margin: 0 auto;
        max-width: 280px;
    }
    
    .author-text .section-header {
        text-align: center;
    }
    
    .author-text .section-divider {
        margin: 0 auto;
    }
    
    .order-content {
        grid-template-columns: 1fr;
        gap: clamp(2rem, 5vw, 3rem);
    }
    
    .order-book {
        order: -1;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: clamp(2rem, 5vw, 3rem);
    }
}

@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: min(300px, 80vw);
        height: 100vh;
        background: var(--color-white);
        flex-direction: column;
        padding: clamp(4rem, 10vw, 5rem) clamp(1.5rem, 4vw, 2rem);
        box-shadow: var(--shadow-2xl);
        transition: right 0.4s cubic-bezier(0.4, 0, 0.2, 1);
        gap: clamp(1.5rem, 4vw, 2rem);
        align-items: flex-start;
        z-index: 999;
    }
    
    .nav-menu.active {
        right: 0;
    }
    
    .nav-menu a {
        width: 100%;
        padding: var(--spacing-md) 0;
        font-size: clamp(1rem, 3vw, 1.125rem);
    }
    
    .nav-cta {
        width: 100%;
        text-align: center;
        padding: var(--spacing-lg) var(--spacing-xl) !important;
    }
    
    .hero {
        padding: clamp(6rem, 12vw, 7rem) 0 clamp(3rem, 6vw, 4rem);
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
    
    .about-book,
    .author,
    .reviews,
    .order {
        padding: clamp(3rem, 8vw, 4rem) 0;
    }
    
    .reviews-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .demo-popup {
        padding: var(--spacing-md);
    }
    
    .demo-popup-content {
        padding: clamp(1.5rem, 5vw, 2rem);
        border-radius: var(--border-radius-lg);
    }
    
    .order-formats {
        grid-template-columns: 1fr;
    }
    
    .format-option {
        padding: clamp(1.5rem, 4vw, 2rem);
    }
}

@media (hover: hover) and (pointer: fine) {
    .btn:hover {
        transform: translateY(-2px);
    }
    
    .btn:active {
        transform: translateY(0);
    }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

@media print {
    .header,
    .nav,
    .demo-popup,
    .footer {
        display: none;
    }
    
    body {
        background: white;
        color: black;
    }
}