/* ================================
   CSS Variables & Design Tokens
   ================================ */
:root {
    /* Colors - Light Mode */
    --background: hsl(30, 30%, 98%);
    --foreground: hsl(340, 20%, 15%);
    
    --card: hsl(0, 0%, 100%);
    --card-foreground: hsl(340, 20%, 15%);
    
    --primary: hsl(340, 45%, 35%);
    --primary-foreground: hsl(0, 0%, 100%);
    
    --secondary: hsl(340, 30%, 92%);
    --secondary-foreground: hsl(340, 45%, 25%);
    
    --muted: hsl(30, 20%, 94%);
    --muted-foreground: hsl(340, 10%, 45%);
    
    --accent: hsl(340, 60%, 45%);
    --accent-foreground: hsl(0, 0%, 100%);
    
    --border: hsl(340, 20%, 88%);
    
    /* Gradients */
    --gradient-hero: linear-gradient(135deg, hsl(340, 45%, 35%) 0%, hsl(340, 60%, 45%) 50%, hsl(350, 50%, 55%) 100%);
    --gradient-warm: linear-gradient(180deg, hsl(30, 30%, 98%) 0%, hsl(340, 30%, 96%) 100%);
    --gradient-card: linear-gradient(145deg, hsl(0, 0%, 100%) 0%, hsl(340, 30%, 98%) 100%);
    
    /* Shadows */
    --shadow-soft: 0 4px 24px -4px hsla(340, 45%, 35%, 0.12);
    --shadow-glow: 0 0 40px hsla(340, 45%, 35%, 0.15);
    
    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-serif: 'Playfair Display', Georgia, serif;
    
    /* Spacing */
    --radius: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-2xl: 2rem;
}

/* ================================
   Base Styles
   ================================ */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--background);
    color: var(--foreground);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-serif);
    line-height: 1.2;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: inherit;
    text-decoration: none;
}

strong {
    color: var(--foreground);
}

/* ================================
   Utility Classes
   ================================ */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.container-sm {
    max-width: 900px;
}

.container-md {
    max-width: 1024px;
}

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

.text-gradient {
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.text-muted {
    color: var(--muted-foreground);
}

.text-primary {
    color: var(--primary);
}

.text-sm {
    font-size: 0.875rem;
}

.text-lg {
    font-size: 1.125rem;
}

.serif {
    font-family: var(--font-serif);
}

.italic {
    font-style: italic;
}

.mt-4 {
    margin-top: 1rem;
}

.mt-12 {
    margin-top: 3rem;
}

.bg-warm {
    background: var(--gradient-warm);
}

/* ================================
   Buttons
   ================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.875rem 1.75rem;
    border-radius: var(--radius-lg);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    text-align: center;
}

.btn-hero {
    background: var(--gradient-hero);
    color: var(--primary-foreground);
    box-shadow: var(--shadow-soft);
}

.btn-hero:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-outline:hover {
    background: var(--secondary);
    transform: translateY(-2px);
}

.btn-lg {
    padding: 1.125rem 2.5rem;
    font-size: 1.125rem;
    border-radius: var(--radius-xl);
}

.btn-arrow {
    width: 1.25rem;
    height: 1.25rem;
    transition: transform 0.3s ease;
}

.btn:hover .btn-arrow {
    transform: translateX(4px);
}

/* ================================
   Cards
   ================================ */
.card {
    background: var(--card);
    border-radius: var(--radius-xl);
    padding: 2rem;
    box-shadow: var(--shadow-soft);
    border: 1px solid hsla(340, 20%, 88%, 0.5);
}

.card-gradient {
    background: var(--gradient-card);
}

.card-accent {
    background: hsla(340, 30%, 92%, 0.5);
    border: 1px solid hsla(340, 45%, 35%, 0.2);
}

.card-hero {
    background: var(--gradient-hero);
    color: var(--primary-foreground);
}

.card-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

/* ================================
   Section Styles
   ================================ */
section {
    padding: 6rem 1rem;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-title {
    font-size: clamp(1.875rem, 5vw, 3rem);
    font-weight: 700;
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: 1.25rem;
    color: var(--muted-foreground);
    max-width: 640px;
    margin: 0 auto;
}

/* ================================
   Hero Section
   ================================ */
.hero-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-warm);
    position: relative;
    overflow: hidden;
    padding: 5rem 1rem;
}

.decorative-blob {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    pointer-events: none;
}

.blob-1 {
    top: 5rem;
    left: 2.5rem;
    width: 18rem;
    height: 18rem;
    background: hsla(340, 45%, 35%, 0.05);
}

.blob-2 {
    bottom: 5rem;
    right: 2.5rem;
    width: 24rem;
    height: 24rem;
    background: hsla(340, 60%, 45%, 0.05);
}

.blob-3 {
    top: 0;
    left: 25%;
    width: 24rem;
    height: 24rem;
    background: hsla(340, 45%, 35%, 0.05);
}

.blob-4 {
    bottom: 0;
    right: 25%;
    width: 18rem;
    height: 18rem;
    background: hsla(340, 60%, 45%, 0.05);
}

.hero-grid {
    display: grid;
    gap: 3rem;
    align-items: center;
    position: relative;
    z-index: 10;
}

@media (min-width: 1024px) {
    .hero-grid {
        grid-template-columns: 1fr 1fr;
        gap: 4rem;
    }
}

.hero-content {
    text-align: center;
}

@media (min-width: 1024px) {
    .hero-content {
        text-align: left;
    }
}

.hero-tagline {
    font-size: 1.125rem;
    color: var(--muted-foreground);
    font-family: var(--font-serif);
    font-style: italic;
    margin-bottom: 1.5rem;
}

.hero-title {
    font-size: clamp(2.25rem, 6vw, 3.75rem);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

.hero-subtitle {
    font-size: clamp(1.125rem, 3vw, 1.5rem);
    color: var(--muted-foreground);
    font-family: var(--font-serif);
    font-style: italic;
    margin-bottom: 1rem;
}

.hero-card {
    background: var(--card);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    box-shadow: var(--shadow-soft);
    border: 1px solid hsla(340, 20%, 88%, 0.5);
    margin-bottom: 2rem;
}

.hero-card p {
    color: var(--muted-foreground);
    line-height: 1.7;
}

.hero-features {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 1rem;
    justify-content: center;
}

@media (min-width: 1024px) {
    .hero-features {
        justify-content: flex-start;
    }
}

.hero-feature {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--muted-foreground);
}

.hero-feature .icon {
    width: 1rem;
    height: 1rem;
    color: var(--primary);
}

.hero-buttons {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    justify-content: center;
}

@media (min-width: 640px) {
    .hero-buttons {
        flex-direction: row;
    }
}

@media (min-width: 1024px) {
    .hero-buttons {
        justify-content: flex-start;
    }
}

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

@media (min-width: 1024px) {
    .hero-book {
        justify-content: flex-end;
    }
}

.book-shadow {
    position: absolute;
    inset: 0;
    background: hsla(340, 45%, 35%, 0.3);
    filter: blur(48px);
    border-radius: var(--radius-2xl);
    transform: translateY(2rem) scale(0.9);
}

.book-cover {
    position: relative;
    transition: transform 0.5s ease;
}

.book-cover:hover {
    transform: scale(1.02) rotate(1deg);
}

.book-cover img {
    width: 100%;
    max-width: 320px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-glow);
}

@media (min-width: 768px) {
    .book-cover img {
        max-width: 380px;
    }
}

/* ================================
   Problem Section
   ================================ */
.problem-section {
    background: var(--background);
}

.problem-cards {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.problem-cards .card p {
    font-size: 1.125rem;
    line-height: 1.7;
}

/* ================================
   What Is Section
   ================================ */
.what-is-section {
    background: var(--gradient-warm);
}

.what-is-grid {
    display: grid;
    gap: 2rem;
}

@media (min-width: 768px) {
    .what-is-grid {
        grid-template-columns: 1fr 1fr;
    }
}

.list-check {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.list-check li {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
}

.list-icon {
    width: 1.5rem;
    height: 1.5rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    margin-top: 0.125rem;
}

.list-icon svg {
    width: 1rem;
    height: 1rem;
}

.list-icon-x {
    background: var(--muted);
}

.list-icon-x svg {
    color: var(--muted-foreground);
}

.list-icon-check {
    background: hsla(0, 0%, 100%, 0.2);
}

.list-icon-check svg {
    color: var(--primary-foreground);
}

/* ================================
   Features Section
   ================================ */
.features-section {
    background: var(--background);
}

.features-grid {
    display: grid;
    gap: 1.5rem;
}

@media (min-width: 640px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

.feature-card {
    background: var(--gradient-card);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    box-shadow: var(--shadow-soft);
    border: 1px solid hsla(340, 20%, 88%, 0.5);
    transition: all 0.3s ease;
}

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

.feature-icon {
    width: 3rem;
    height: 3rem;
    border-radius: var(--radius-lg);
    background: var(--gradient-hero);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
    transition: transform 0.3s ease;
}

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

.feature-icon svg {
    width: 1.5rem;
    height: 1.5rem;
    color: var(--primary-foreground);
}

.feature-card h3 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    font-family: var(--font-sans);
}

.feature-card p {
    font-size: 0.875rem;
    color: var(--muted-foreground);
}

/* ================================
   Benefits Section
   ================================ */
.benefits-section {
    background: var(--gradient-warm);
}

.benefits-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.benefit-item {
    background: var(--card);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-soft);
    border: 1px solid hsla(340, 20%, 88%, 0.5);
    display: flex;
    align-items: center;
    gap: 1rem;
    transition: all 0.3s ease;
}

.benefit-item:hover {
    box-shadow: var(--shadow-glow);
}

.benefit-icon {
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    background: var(--secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.benefit-icon svg {
    width: 1.5rem;
    height: 1.5rem;
    color: var(--primary);
}

.benefit-item p {
    font-size: 1.125rem;
}

/* ================================
   Application Section
   ================================ */
.application-section {
    background: var(--background);
}

.topics-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
    margin-bottom: 3rem;
}

.topic-tag {
    padding: 0.625rem 1.25rem;
    background: var(--secondary);
    border-radius: 9999px;
    color: var(--secondary-foreground);
    font-weight: 500;
    transition: all 0.3s ease;
    cursor: default;
}

.topic-tag:hover {
    background: var(--primary);
    color: var(--primary-foreground);
}

/* ================================
   Differentiator Section
   ================================ */
.differentiator-section {
    background: var(--gradient-warm);
}

.diff-grid {
    display: grid;
    gap: 1rem;
    margin-bottom: 3rem;
}

@media (min-width: 640px) {
    .diff-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

.diff-item {
    background: var(--card);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-soft);
    border: 1px solid hsla(340, 20%, 88%, 0.5);
    display: flex;
    align-items: center;
    gap: 1rem;
}

.star-icon {
    width: 1.25rem;
    height: 1.25rem;
    color: var(--primary);
    flex-shrink: 0;
}

.diff-item p {
    font-weight: 500;
}

.diff-highlight {
    background: var(--gradient-hero);
    border-radius: var(--radius-xl);
    padding: 2rem;
    text-align: center;
    color: var(--primary-foreground);
    box-shadow: var(--shadow-glow);
}

.diff-highlight p {
    font-size: 1.25rem;
    font-family: var(--font-serif);
}

/* ================================
   Result Section
   ================================ */
.result-section {
    background: var(--background);
}

.results-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 3rem;
}

.result-item {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.result-icon {
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 50%;
    background: var(--gradient-hero);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: transform 0.3s ease;
}

.result-item:hover .result-icon {
    transform: scale(1.1);
}

.result-icon svg {
    width: 1.25rem;
    height: 1.25rem;
    color: var(--primary-foreground);
}

.result-item p {
    font-size: 1.25rem;
    font-weight: 500;
}

.result-quote {
    text-align: center;
    font-size: 1.5rem;
    font-weight: 700;
    font-family: var(--font-serif);
    font-style: italic;
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ================================
   CTA Section
   ================================ */
.cta-section {
    background: var(--gradient-warm);
    position: relative;
    overflow: hidden;
}

.cta-card {
    background: var(--card);
    border-radius: var(--radius-2xl);
    padding: 2rem;
    box-shadow: var(--shadow-glow);
    border: 1px solid hsla(340, 20%, 88%, 0.5);
    text-align: center;
    position: relative;
    z-index: 10;
}

@media (min-width: 768px) {
    .cta-card {
        padding: 3rem;
    }
}

.cta-icon {
    width: 4rem;
    height: 4rem;
    border-radius: var(--radius-xl);
    background: var(--gradient-hero);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.cta-icon svg {
    width: 2rem;
    height: 2rem;
    color: var(--primary-foreground);
}

.cta-title {
    font-size: clamp(1.5rem, 4vw, 2.25rem);
    font-weight: 700;
    margin-bottom: 1rem;
}

.cta-subtitle {
    font-size: 1.125rem;
    color: var(--muted-foreground);
    margin-bottom: 1.5rem;
    max-width: 560px;
    margin-left: auto;
    margin-right: auto;
}

.cta-quote {
    background: hsla(340, 30%, 92%, 0.5);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.cta-quote .serif {
    margin-bottom: 0.5rem;
}

.cta-final {
    font-size: 1.25rem;
    font-weight: 500;
    margin-bottom: 2rem;
}

/* Pricing Block */
.pricing-block {
    background: var(--gradient-card);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    margin-bottom: 2rem;
    border: 1px solid hsla(340, 20%, 88%, 0.5);
}

.pricing-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--muted-foreground);
    margin-bottom: 0.5rem;
}

.pricing-amount {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.pricing-amount .price {
    font-size: clamp(2.25rem, 5vw, 3rem);
    font-weight: 700;
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.pricing-amount .currency {
    font-size: 1.125rem;
    color: var(--muted-foreground);
}

/* Payment Methods */
.payment-methods {
    border-top: 1px solid hsla(340, 20%, 88%, 0.5);
    padding-top: 1rem;
    margin-top: 1rem;
}

.payment-label {
    font-size: 0.75rem;
    color: var(--muted-foreground);
    margin-bottom: 0.75rem;
}

.payment-options {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
}

.payment-option {
    background: var(--card);
    border-radius: var(--radius-lg);
    padding: 0.5rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--foreground);
    border: 1px solid hsla(340, 20%, 88%, 0.3);
}

.cta-info {
    font-size: 0.875rem;
    color: var(--muted-foreground);
    margin-top: 1.5rem;
}

/* ================================
   Footer
   ================================ */
.footer {
    padding: 2rem 1rem;
    background: var(--background);
    border-top: 1px solid var(--border);
    text-align: center;
}

.footer p {
    font-size: 0.875rem;
    color: var(--muted-foreground);
}

/* ================================
   Animations
   ================================ */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.animate-on-scroll.slide-left {
    transform: translateX(-30px);
}

.animate-on-scroll.slide-right {
    transform: translateX(30px);
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0) translateX(0);
}

/* Icon base styles */
.icon {
    width: 1em;
    height: 1em;
    vertical-align: middle;
}

/* ================================
   Responsive Adjustments
   ================================ */
@media (max-width: 639px) {
    section {
        padding: 4rem 1rem;
    }
    
    .section-header {
        margin-bottom: 2.5rem;
    }
    
    .card {
        padding: 1.5rem;
    }
}

/* ================================
   Floating CTA Button
   ================================ */
.floating-cta {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    background: var(--gradient-hero);
    color: var(--primary-foreground);
    border-radius: 9999px;
    font-weight: 600;
    font-size: 0.875rem;
    box-shadow: 0 4px 20px hsla(340, 45%, 35%, 0.3);
    z-index: 1000;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.4s ease;
    pointer-events: none;
    text-decoration: none;
}

.floating-cta.visible {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}

.floating-cta:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 28px hsla(340, 45%, 35%, 0.4);
}

.floating-cta svg {
    width: 1rem;
    height: 1rem;
    transition: transform 0.3s ease;
}

.floating-cta:hover svg {
    transform: translateX(3px);
}

@media (max-width: 639px) {
    .floating-cta {
        bottom: 1rem;
        right: 1rem;
        padding: 0.625rem 1rem;
        font-size: 0.8rem;
    }
}