:root {
    --bg-color: #050505;
    --text-main: #ffffff;
    --text-muted: #888888;
    --accent-color: #D4FF00;
    /* Neon Lime */
    --accent-glow: rgba(212, 255, 0, 0.4);
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.1);
    --font-heading: 'Inter', sans-serif;
    --font-body: 'Noto Sans KR', sans-serif;
    --spacing-container: 2rem;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: var(--font-body);
    overflow-x: hidden;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* Background Noise Effect */
.noise-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 9999;
    opacity: 0.05;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
}

/* Typography & Utilities */
h1,
h2,
h3 {
    font-family: var(--font-heading);
    font-weight: 800;
    letter-spacing: -0.03em;
}

.container {
    max-width: 600px;
    margin: 0 auto;
    padding: 0 var(--spacing-container);
}

.container__wide {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-container);
}

.highlight {
    color: var(--accent-color);
    text-shadow: 0 0 20px var(--accent-glow);
}

.gradient-text {
    background: linear-gradient(90deg, #fff, var(--text-muted));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: 1.5rem var(--spacing-container);
    z-index: 100;
    mix-blend-mode: difference;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: -0.05em;
}

/* Hero Section */
.hero-section {
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
    padding-top: 4rem;
}

.hero-text {
    font-size: clamp(2.5rem, 6vw, 5rem);
    line-height: 1.1;
    margin-bottom: 2rem;
}

.hero-sub {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: var(--text-muted);
    font-weight: 300;
    max-width: 400px;
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.75rem;
    color: var(--text-muted);
}

.scroll-indicator .line {
    width: 1px;
    height: 40px;
    background: linear-gradient(to bottom, var(--text-muted), transparent);
}

/* Concept Section */
.concept-section {
    padding: 10rem 0;
    text-align: center;
}

.section-title {
    font-size: clamp(2rem, 4vw, 3.5rem);
    margin-bottom: 1.5rem;
}

.section-desc {
    color: var(--text-muted);
    font-size: 1.1rem;
}

/* Feature Section */
.feature-section {
    padding: 5rem var(--spacing-container);
    display: flex;
    justify-content: center;
}

.glass-card {
    position: relative;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 4rem 2rem;
    border-radius: 24px;
    text-align: center;
    width: 100%;
    max-width: 400px;
    overflow: hidden;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
}

.card-content {
    position: relative;
    z-index: 2;
}

.glass-card h3 {
    font-size: 1rem;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 1rem;
    letter-spacing: 0.1em;
}

.feature-highlight {
    font-size: 2rem;
    font-weight: 700;
    line-height: 1.3;
}

.abstract-shape {
    position: absolute;
    top: -50%;
    right: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at center, rgba(212, 255, 0, 0.1) 0%, transparent 60%);
    pointer-events: none;
    z-index: 1;
}

/* CTA Section */
.cta-section {
    padding: 8rem 0;
    text-align: center;
}

.cta-message {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    font-weight: 600;
}

.btn-primary {
    background: var(--accent-color);
    color: #000;
    border: none;
    padding: 1.2rem 3rem;
    font-size: 1.2rem;
    font-weight: 700;
    border-radius: 100px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 0.8rem;
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 0.3s ease;
}

.btn-primary:hover {
    transform: scale(1.05);
    box-shadow: 0 0 30px var(--accent-glow);
}

.btn-primary svg {
    transition: transform 0.3s ease;
}

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

/* Content Section (FAQ) */
.content-section {
    padding: 5rem 0;
    background: linear-gradient(to bottom, transparent, rgba(255, 255, 255, 0.02));
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    text-align: left;
}

.faq-item {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--glass-border);
    padding: 2rem;
    border-radius: 16px;
    transition: transform 0.3s ease;
}

.faq-item:hover {
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.05);
}

.faq-item h3 {
    font-size: 1.1rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
    line-height: 1.4;
}

.faq-item p {
    font-size: 0.95rem;
    color: #ccc;
    line-height: 1.6;
}

/* Footer */
footer {
    padding: 3rem 2rem;
    text-align: center;
    font-size: 0.85rem;
    color: #444;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    margin-top: 4rem;
}

.footer-links {
    margin-bottom: 1rem;
}

.footer-links a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s;
}

.footer-links a:hover {
    color: var(--text-main);
    text-decoration: underline;
}

.footer-links .divider {
    margin: 0 0.5rem;
    color: #333;
}

.copyright {
    color: #444;
}

/* Animations */
.block-reveal {
    display: inline-block;
    opacity: 0;
    transform: translateY(20px);
    animation: revealUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.block-reveal:nth-child(2) {
    animation-delay: 0.1s;
}

.block-reveal:nth-child(4) {
    animation-delay: 0.2s;
}

/* br tag counts as child */

.fade-in-up {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 1s ease forwards;
}

.fade-in {
    opacity: 0;
    animation: fadeIn 1s ease forwards;
}

.delay-1 {
    animation-delay: 0.4s;
}

.delay-2 {
    animation-delay: 0.8s;
}

@keyframes revealUp {
    from {
        opacity: 0;
        transform: translateY(40px) skewY(2deg);
    }

    to {
        opacity: 1;
        transform: translateY(0) skewY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

.fade-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

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

/* Mobile Adjustments */
@media (max-width: 768px) {
    .hero-text {
        font-size: 2.8rem;
    }

    .btn-primary {
        width: 100%;
        justify-content: center;
    }
}

/* Quiz Overlay & Container */
.quiz-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 1000;
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 1;
    transition: opacity 0.3s ease;
}

.quiz-overlay.hidden {
    opacity: 0;
    pointer-events: none;
    visibility: hidden;
}

.quiz-container {
    width: 90%;
    max-width: 500px;
    padding: 3rem 2rem;
    position: relative;
    /* Reuse glass-card styles but override some if needed */
    text-align: left;
    display: flex;
    flex-direction: column;
}

.close-btn {
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 2rem;
    cursor: pointer;
    transition: color 0.2s;
}

.close-btn:hover {
    color: var(--text-main);
}

/* Question Section */
.question-number {
    color: var(--accent-color);
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.question-text {
    font-size: 1.5rem;
    font-weight: 600;
    /* Pretendard/Inter looks good with 600 */
    margin-bottom: 2.5rem;
    line-height: 1.4;
    min-height: 4rem;
    /* Prevent layout jump */
}

/* Options */
.options-container {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.option-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    padding: 1.5rem;
    border-radius: 16px;
    color: var(--text-main);
    text-align: left;
    cursor: pointer;
    display: flex;
    align-items: center;
    /* Center items vertically */
    gap: 1rem;
    transition: all 0.3s ease;
}

.option-btn:hover,
.option-btn:active {
    background: rgba(212, 255, 0, 0.1);
    border-color: var(--accent-color);
    transform: translateY(-2px);
}

.option-label {
    font-weight: 700;
    color: var(--accent-color);
    flex-shrink: 0;
}

.option-text {
    font-size: 1rem;
    line-height: 1.4;
}

/* Result Section */
#quiz-result-section {
    text-align: center;
    animation: fadeIn 0.5s ease;
}

.result-header {
    font-size: 1rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.result-title {
    font-size: 2rem;
    color: var(--accent-color);
    margin-bottom: 1.5rem;
    text-shadow: 0 0 15px var(--accent-glow);
}

.result-desc {
    font-size: 1rem;
    color: #ddd;
    line-height: 1.7;
    margin-bottom: 2.5rem;
    white-space: pre-line;
    /* Handle line breaks from logic */
    text-align: left;
    background: rgba(255, 255, 255, 0.03);
    padding: 1.5rem;
    border-radius: 12px;
}

.result-action-box {
    border: 1px solid var(--accent-color);
    background: rgba(212, 255, 0, 0.05);
    padding: 1.5rem;
    border-radius: 16px;
    margin-bottom: 2rem;
    text-align: center;
}

.action-label {
    font-size: 0.9rem;
    color: var(--accent-color);
    margin-bottom: 0.8rem;
    font-weight: 600;
}

.action-text {
    font-size: 1.1rem;
    font-weight: 700;
    line-height: 1.5;
}

.hidden {
    display: none !important;
}

/* Progress Bar */
.progress-bar {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: rgba(255, 255, 255, 0.1);
}

.progress-fill {
    height: 100%;
    background: var(--accent-color);
    width: 0%;
    transition: width 0.3s ease;
    box-shadow: 0 0 10px var(--accent-glow);
}