/* =============================================
   RESET & BASE
============================================= */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg-dark: #0a0f0a;
    --bg-card: rgba(255, 255, 255, 0.03);
    --glass: rgba(255, 255, 255, 0.06);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-strong: rgba(255, 255, 255, 0.1);
    --green-accent: #4a7c59;
    --green-light: #6b9b7a;
    --green-glow: rgba(74, 124, 89, 0.3);
    --text-primary: rgba(255, 255, 255, 0.92);
    --text-secondary: rgba(255, 255, 255, 0.6);
    --text-muted: rgba(255, 255, 255, 0.4);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
}

/* =============================================
   ANIMATED BACKGROUND LAYERS
============================================= */
.bg-layer {
    position: fixed;
    inset: -20px;
    z-index: -2;
    background-size: cover;
    background-position: center;
    will-change: transform;
}

.bg-layer-1 {
    background-image: url('https://images.unsplash.com/photo-1518531933037-91b2f5f229cc?w=1920&q=80');
    animation: bgSway1 20s ease-in-out infinite;
}

.bg-layer-2 {
    background-image: url('https://images.unsplash.com/photo-1518531933037-91b2f5f229cc?w=1920&q=80');
    opacity: 0.5;
    transform: scale(1.1);
    animation: bgSway2 25s ease-in-out infinite;
}

.bg-overlay {
    position: fixed;
    inset: 0;
    z-index: -1;
    background: linear-gradient(180deg, 
        rgba(10, 15, 10, 0.3) 0%, 
        rgba(10, 15, 10, 0.6) 30%,
        rgba(10, 15, 10, 0.8) 60%,
        rgba(10, 15, 10, 0.92) 100%
    );
}

@keyframes bgSway1 {
    0%, 100% { transform: scale(1.05) translateX(0) translateY(0); }
    25% { transform: scale(1.08) translateX(-10px) translateY(-5px); }
    50% { transform: scale(1.05) translateX(5px) translateY(-10px); }
    75% { transform: scale(1.07) translateX(-5px) translateY(5px); }
}

@keyframes bgSway2 {
    0%, 100% { transform: scale(1.15) translateX(0) translateY(0); }
    33% { transform: scale(1.12) translateX(15px) translateY(10px); }
    66% { transform: scale(1.18) translateX(-10px) translateY(-5px); }
}

/* Subtle grain texture */
body::after {
    content: '';
    position: fixed;
    inset: 0;
    background: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
    opacity: 0.03;
    pointer-events: none;
    z-index: 100;
}

/* =============================================
   LAYOUT
============================================= */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

section {
    padding: 100px 0;
}

/* =============================================
   TYPOGRAPHY
============================================= */
h1, h2, h3, h4 {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 500;
    letter-spacing: -0.02em;
}

h1 {
    font-size: clamp(2.5rem, 8vw, 5rem);
    line-height: 1.1;
    font-weight: 600;
}

h2 {
    font-size: clamp(1.8rem, 4vw, 2.5rem);
    margin-bottom: 1em;
}

h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5em;
}

h4 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--green-light);
    margin-bottom: 0.75em;
}

p {
    color: var(--text-secondary);
}

.section-title {
    text-align: center;
    margin-bottom: 60px;
    color: var(--text-primary);
}

/* =============================================
   SOUND TOGGLE
============================================= */
.sound-toggle {
    position: fixed;
    top: 24px;
    right: 24px;
    z-index: 1000;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    outline: none;
    padding: 0;
}

.sound-toggle:hover {
    background: var(--glass-strong);
    transform: scale(1.05);
}

.sound-toggle:active {
    transform: scale(0.95);
}

.sound-toggle.playing {
    background: var(--green-glow);
    border-color: var(--green-accent);
}

.sound-icon {
    width: 20px;
    height: 20px;
    color: var(--text-secondary);
    transition: color 0.3s ease;
}

.sound-toggle.playing .sound-icon {
    color: var(--green-light);
}

.sound-waves {
    opacity: 0.3;
    transition: opacity 0.3s ease;
}

.sound-toggle.playing .sound-waves {
    opacity: 1;
    animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

/* =============================================
   THEME TOGGLE (DARK/LIGHT)
============================================= */
.theme-toggle {
    position: fixed;
    top: 24px;
    right: 80px;
    z-index: 1000;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    outline: none;
    padding: 0;
}

.theme-toggle:hover {
    background: var(--glass-strong);
    transform: scale(1.05);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    color: var(--text-secondary);
    transition: all 0.3s ease;
    position: absolute;
}

.sun-icon {
    opacity: 0;
    transform: rotate(-90deg) scale(0.5);
}

.moon-icon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
}

/* Light Mode */
body.light-mode {
    --bg-dark: #f5f7f0;
    --bg-card: rgba(0, 0, 0, 0.03);
    --glass: rgba(0, 0, 0, 0.05);
    --glass-border: rgba(0, 0, 0, 0.08);
    --glass-strong: rgba(0, 0, 0, 0.08);
    --text-primary: rgba(0, 0, 0, 0.9);
    --text-secondary: rgba(0, 0, 0, 0.6);
    --text-muted: rgba(0, 0, 0, 0.4);
}

body.light-mode .bg-overlay {
    background: linear-gradient(180deg, 
        rgba(245, 247, 240, 0.3) 0%, 
        rgba(245, 247, 240, 0.7) 30%,
        rgba(245, 247, 240, 0.9) 60%,
        rgba(245, 247, 240, 0.98) 100%
    );
}

body.light-mode .sun-icon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
}

body.light-mode .moon-icon {
    opacity: 0;
    transform: rotate(90deg) scale(0.5);
}

/* =============================================
   STATS SECTION
============================================= */
.stats {
    padding: 60px 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.stat-card {
    background: var(--glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 32px 24px;
    text-align: center;
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-4px);
    border-color: var(--green-accent);
}

.stat-num {
    display: block;
    font-family: 'Space Grotesk', sans-serif;
    font-size: 3rem;
    font-weight: 600;
    color: var(--green-light);
    line-height: 1;
}

.stat-unit {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--green-light);
    margin-left: 4px;
}

.stat-label {
    display: block;
    margin-top: 12px;
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.4;
}

/* =============================================
   ANATOMY SECTION
============================================= */
.anatomy {
    padding: 100px 0;
}

.anatomy-container {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 60px;
    align-items: start;
}

.body-visual {
    position: sticky;
    top: 100px;
}

.body-svg {
    width: 100%;
    max-width: 200px;
    margin: 0 auto;
    display: block;
    color: var(--text-muted);
}

.body-outline {
    transition: all 0.3s ease;
}

.organ {
    opacity: 0.7;
    cursor: pointer;
    transition: all 0.3s ease;
}

.organ:hover,
.organ.active {
    opacity: 1;
    filter: drop-shadow(0 0 15px var(--green-accent)) drop-shadow(0 0 30px var(--green-glow));
}

.organ ellipse,
.organ path,
.organ circle {
    transition: all 0.3s ease;
}

.organ.active ellipse,
.organ.active path {
    stroke-width: 2;
}

.anatomy-info {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.anatomy-card {
    background: var(--glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 28px;
    opacity: 0.6;
    transform: translateX(20px);
    transition: all 0.4s ease;
    cursor: pointer;
}

.anatomy-card:hover,
.anatomy-card.active {
    opacity: 1;
    transform: translateX(0);
    border-color: var(--green-accent);
}

.anatomy-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 12px;
    color: var(--green-accent);
}

.anatomy-icon svg {
    width: 100%;
    height: 100%;
}

.anatomy-card h3 {
    font-size: 1.3rem;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.anatomy-card p {
    font-size: 0.95rem;
    line-height: 1.7;
    margin-bottom: 10px;
}

.anatomy-card p:last-child {
    margin-bottom: 0;
}

/* =============================================
   HERO
============================================= */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    padding: 40px 24px;
}

.hero-inner {
    max-width: 800px;
}

.hero-tag {
    display: inline-block;
    padding: 8px 20px;
    background: var(--glass);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 100px;
    font-size: 0.85rem;
    color: var(--green-light);
    letter-spacing: 0.05em;
    margin-bottom: 32px;
}

.hero h1 {
    margin-bottom: 24px;
    background: linear-gradient(180deg, var(--text-primary) 0%, var(--text-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 60px;
}

.scroll-hint {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    color: var(--text-muted);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.15em;
}

.scroll-line {
    width: 1px;
    height: 60px;
    background: linear-gradient(180deg, var(--text-muted) 0%, transparent 100%);
    animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
    0%, 100% { opacity: 0.3; transform: scaleY(1); }
    50% { opacity: 1; transform: scaleY(1.2); }
}

/* =============================================
   INTRO
============================================= */
.intro {
    padding: 80px 0;
}

.intro-glass {
    background: var(--glass);
    backdrop-filter: blur(40px);
    -webkit-backdrop-filter: blur(40px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 60px;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.intro-glass h2 {
    margin-bottom: 20px;
}

.intro-glass p {
    font-size: 1.1rem;
    line-height: 1.8;
}

/* =============================================
   COMPARISON CARDS
============================================= */
.comparison {
    padding: 100px 0;
}

.compare-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
}

.compare-card {
    background: var(--glass);
    backdrop-filter: blur(40px);
    -webkit-backdrop-filter: blur(40px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    overflow: hidden;
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.compare-card:hover {
    transform: translateY(-4px);
    border-color: rgba(255, 255, 255, 0.15);
}

.card-header {
    padding: 32px 28px 24px;
    display: flex;
    align-items: center;
    gap: 16px;
    border-bottom: 1px solid var(--glass-border);
}

.card-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
    background: var(--glass-strong);
    border: 1px solid var(--glass-border);
}

.card-icon svg {
    width: 24px;
    height: 24px;
    color: var(--green-light);
}

.card-header h3 {
    color: var(--text-primary);
    margin: 0;
}

.card-body {
    padding: 28px;
}

.info-block {
    margin-bottom: 28px;
}

.info-block:last-child {
    margin-bottom: 0;
}

.info-block ul {
    list-style: none;
}

.info-block li {
    padding: 6px 0;
    padding-left: 16px;
    position: relative;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.info-block li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 14px;
    width: 4px;
    height: 4px;
    background: var(--green-accent);
    border-radius: 50%;
}

.info-block li strong {
    color: var(--text-primary);
}

/* =============================================
   MYTHS
============================================= */
.myths {
    padding: 100px 0;
}

.myth-grid {
    display: grid;
    gap: 32px;
    max-width: 900px;
    margin: 0 auto;
}

.myth-card {
    background: var(--glass);
    backdrop-filter: blur(40px);
    -webkit-backdrop-filter: blur(40px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 40px;
}

.myth-label {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.myth-tag {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    padding: 6px 12px;
    background: var(--glass-strong);
    border-radius: 6px;
    color: var(--text-muted);
}

.myth-verdict {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    padding: 6px 12px;
    background: rgba(180, 80, 80, 0.2);
    border-radius: 6px;
    color: #d4a0a0;
}

.myth-card blockquote {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.4rem;
    font-style: italic;
    color: var(--text-primary);
    margin-bottom: 28px;
    padding-left: 20px;
    border-left: 2px solid var(--green-accent);
}

.myth-truth h4 {
    margin-bottom: 12px;
}

.myth-truth p {
    margin-bottom: 12px;
    font-size: 0.95rem;
    line-height: 1.8;
}

.myth-truth p:last-child {
    margin-bottom: 0;
}

/* =============================================
   TIPS
============================================= */
.tips {
    padding: 100px 0;
}

.tips-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.tip {
    background: var(--glass);
    backdrop-filter: blur(40px);
    -webkit-backdrop-filter: blur(40px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 28px;
    display: flex;
    gap: 20px;
    align-items: flex-start;
    transition: transform 0.3s ease;
}

.tip:hover {
    transform: translateY(-2px);
}

.tip-num {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--green-accent);
    line-height: 1;
    opacity: 0.6;
}

.tip p {
    font-size: 0.95rem;
    margin: 0;
}

/* =============================================
   CONCLUSION
============================================= */
.conclusion {
    padding: 100px 0;
}

.conclusion-box {
    background: linear-gradient(135deg, var(--glass-strong) 0%, var(--glass) 100%);
    backdrop-filter: blur(40px);
    -webkit-backdrop-filter: blur(40px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 60px;
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.conclusion-box h2 {
    margin-bottom: 16px;
}

.conclusion-box .lead {
    font-size: 1.3rem;
    color: var(--green-light);
    margin-bottom: 24px;
}

.conclusion-box p {
    margin-bottom: 16px;
    font-size: 1rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.conclusion-cta {
    margin-top: 40px;
    padding-top: 40px;
    border-top: 1px solid var(--glass-border);
}

.conclusion-cta p {
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.conclusion-cta strong {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.5rem;
    color: var(--text-primary);
}

/* =============================================
   FOOTER
============================================= */
footer {
    padding: 80px 0;
    border-top: 1px solid var(--glass-border);
}

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

.footer-hashtag {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 2rem;
    font-weight: 600;
    color: var(--green-light);
    margin-bottom: 16px;
}

.footer-inner > p {
    margin-bottom: 32px;
}

.sources {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.sources span {
    color: var(--text-secondary);
}

/* =============================================
   ANIMATIONS
============================================= */
@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-inner {
    animation: fadeUp 1s ease-out;
}

/* =============================================
   QUIZ SECTION
============================================= */
.quiz {
    padding: 80px 0;
}

.quiz-box {
    max-width: 600px;
    margin: 0 auto;
    background: var(--glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 40px;
}

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

.q-num {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--green-light);
    margin-bottom: 16px;
}

.quiz-question h3 {
    font-size: 1.4rem;
    color: var(--text-primary);
    margin-bottom: 32px;
    line-height: 1.4;
}

.answers {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.answer-btn {
    padding: 16px 20px;
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.answer-btn:hover {
    background: var(--glass-strong);
    border-color: var(--green-accent);
    transform: translateY(-2px);
}

.answer-btn.correct {
    background: rgba(74, 124, 89, 0.3);
    border-color: var(--green-accent);
    color: var(--green-light);
}

.answer-btn.wrong {
    background: rgba(200, 80, 80, 0.2);
    border-color: rgba(200, 80, 80, 0.5);
    color: rgba(255, 150, 150, 1);
}

.answer-btn:disabled {
    cursor: not-allowed;
    opacity: 0.7;
}

.quiz-feedback {
    margin-top: 24px;
    font-size: 0.95rem;
    color: var(--text-secondary);
    min-height: 24px;
}

.quiz-progress {
    margin-top: 32px;
    height: 4px;
    background: var(--glass);
    border-radius: 2px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    width: 0%;
    background: linear-gradient(90deg, var(--green-accent), var(--green-light));
    border-radius: 2px;
    transition: width 0.4s ease;
}

.quiz-result {
    display: none;
    text-align: center;
}

.quiz-result.show {
    display: block;
}

.quiz-result h3 {
    font-size: 2rem;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.quiz-result h3 span {
    color: var(--green-light);
}

.quiz-result p {
    margin-bottom: 24px;
}

.restart-btn {
    padding: 14px 32px;
    background: linear-gradient(135deg, var(--green-accent), var(--green-light));
    border: none;
    border-radius: 12px;
    color: white;
    font-family: inherit;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.restart-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px var(--green-glow);
}

/* =============================================
   RESPONSIVE
============================================= */
@media (max-width: 1024px) {
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .anatomy-container {
        grid-template-columns: 1fr;
    }
    
    .body-visual {
        position: relative;
        top: 0;
        max-width: 200px;
        margin: 0 auto 40px;
    }
}

@media (max-width: 768px) {
    section {
        padding: 60px 0;
    }

    .intro-glass {
        padding: 40px 28px;
    }

    .compare-grid {
        grid-template-columns: 1fr;
    }

    .myth-card {
        padding: 28px;
    }

    .myth-card blockquote {
        font-size: 1.15rem;
    }

    .conclusion-box {
        padding: 40px 28px;
    }

    .sound-toggle {
        top: 16px;
        right: 16px;
        width: 44px;
        height: 44px;
    }
    
    .theme-toggle {
        top: 16px;
        right: 68px;
        width: 44px;
        height: 44px;
    }
    
    .stat-num {
        font-size: 2.2rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .hero {
        padding: 24px 16px;
    }

    .tips-grid {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .answers {
        grid-template-columns: 1fr;
    }
}