/**
 * Korea Vibe Coding Academy - Stylesheet
 * Premium minimal design inspired by Vercel, Linear, Notion
 *
 * Color System:
 * --color-bg:       #f7f6f2   (Warm paper white)
 * --color-surface:  #ffffff   (Card/section surface)
 * --color-ink:      #111010   (Primary text - warm black)
 * --color-ink-2:    #3d3c3a   (Secondary text)
 * --color-muted:    #7a7873   (Muted text)
 * --color-accent:   #1d4ed8   (Deep blue accent)
 * --color-price:    #c2410c   (Burnt orange for pricing)
 * --color-border:   #e2e0da   (Border/divider)
 */

/* ========================================
   CSS Variables & Reset
   ======================================== */

:root {
    /* Colors */
    --color-bg: #f7f6f2;
    --color-surface: #ffffff;
    --color-ink: #111010;
    --color-ink-2: #3d3c3a;
    --color-muted: #7a7873;
    --color-accent: #1d4ed8;
    --color-accent-light: #dbeafe;
    --color-accent-dark: #1e3a8a;
    --color-price: #c2410c;
    --color-price-light: #ffedd5;
    --color-success: #166534;
    --color-success-light: #dcfce7;
    --color-border: #e2e0da;
    --color-border-dark: #cccac4;

    /* Typography - Pretendard for better readability */
    --font-sans: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
    --font-heading: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
    --font-mono: 'IBM Plex Mono', 'SF Mono', monospace;

    /* Spacing */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-2xl: 48px;
    --space-3xl: 64px;
    --space-4xl: 96px;

    /* Layout */
    --max-width: 1200px;
    --nav-height: 64px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.05), 0 1px 3px rgba(0,0,0,0.08);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.05), 0 4px 6px rgba(0,0,0,0.05);

    /* Border Radius */
    --radius-sm: 2px;
    --radius-md: 4px;
    --radius-lg: 8px;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--nav-height);
}

body {
    font-family: var(--font-sans);
    font-size: 15px;
    line-height: 1.7;
    color: var(--color-ink);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

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

/* ========================================
   Typography
   ======================================== */

h1, h2, h3, h4, h5, h6 {
    font-weight: 400;
    line-height: 1.2;
}

.section-eyebrow {
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 500;
    letter-spacing: 3px;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: var(--space-md);
    display: block;
}

.section-title {
    font-family: var(--font-heading);
    font-size: clamp(28px, 5vw, 36px);
    font-weight: 700;
    color: var(--color-ink);
    margin-bottom: var(--space-md);
}

.section-subtitle {
    font-size: 16px;
    color: var(--color-muted);
    max-width: 540px;
}

/* ========================================
   Layout
   ======================================== */

.section-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-3xl);
}

.section-header .section-subtitle {
    margin: 0 auto;
}

/* ========================================
   Buttons
   ======================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: 14px 28px;
    font-family: var(--font-sans);
    font-size: 14px;
    font-weight: 500;
    border-radius: var(--radius-sm);
    transition: all var(--transition-base);
    white-space: nowrap;
}

.btn-icon {
    flex-shrink: 0;
    transition: transform var(--transition-base);
}

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

.btn-primary {
    background-color: var(--color-accent);
    color: white;
    border: 1px solid var(--color-accent);
}

.btn-primary:hover {
    background-color: var(--color-accent-dark);
    border-color: var(--color-accent-dark);
}

.btn-secondary {
    background-color: var(--color-surface);
    color: var(--color-ink);
    border: 1px solid var(--color-border);
}

.btn-secondary:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

.btn-ghost {
    background-color: transparent;
    color: var(--color-ink);
    border: 1px solid var(--color-border-dark);
}

.btn-ghost:hover {
    border-color: var(--color-ink);
}

.btn-kakao {
    background-color: #FEE500;
    color: #3C1E1E;
    border: none;
    gap: var(--space-sm);
}

.btn-kakao:hover {
    background-color: #F5DC00;
}

/* ========================================
   Navigation
   ======================================== */

.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    transition: transform var(--transition-base);
}

.nav.hidden {
    transform: translateY(-100%);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.nav-logo-text {
    font-family: var(--font-heading);
    font-size: 18px;
    color: var(--color-ink);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.nav-link {
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.5px;
    color: var(--color-muted);
    transition: color var(--transition-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background-color: var(--color-accent);
    transition: width var(--transition-base);
}

.nav-link:hover {
    color: var(--color-ink);
}

.nav-link:hover::after {
    width: 100%;
}

.nav-link-cta {
    padding: 10px 20px;
    background-color: var(--color-ink);
    color: white;
    border-radius: var(--radius-sm);
}

.nav-link-cta::after {
    display: none;
}

.nav-link-cta:hover {
    background-color: var(--color-ink-2);
    color: white;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    width: 24px;
    height: 24px;
    justify-content: center;
}

.nav-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background-color: var(--color-ink);
    transition: all var(--transition-base);
}

/* Mobile Menu */
.mobile-menu {
    display: none;
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--color-surface);
    z-index: 999;
    padding: var(--space-xl);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
}

.mobile-menu.active {
    opacity: 1;
    visibility: visible;
}

.mobile-menu-links {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.mobile-menu-link {
    font-family: var(--font-heading);
    font-size: 24px;
    color: var(--color-ink);
    padding: var(--space-md) 0;
    border-bottom: 1px solid var(--color-border);
}

.mobile-menu-cta {
    margin-top: var(--space-xl);
    background-color: var(--color-accent);
    color: white;
    padding: var(--space-md) var(--space-xl);
    text-align: center;
    border-radius: var(--radius-sm);
    border: none;
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .nav-toggle {
        display: flex;
    }

    .mobile-menu {
        display: block;
    }
}

/* ========================================
   Hero Section
   ======================================== */

.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
    overflow: hidden;
    padding-top: var(--nav-height);
}

.hero-bg-gradient {
    position: absolute;
    top: -120px;
    right: -120px;
    width: 480px;
    height: 480px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(29, 78, 216, 0.08) 0%, transparent 70%);
    pointer-events: none;
}

.hero-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-4xl) var(--space-xl);
    position: relative;
    z-index: 1;
}

.hero-content {
    max-width: 720px;
}

.hero-eyebrow {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-xl);
}

.hero-eyebrow-dot {
    width: 8px;
    height: 8px;
    background-color: var(--color-accent);
    border-radius: 50%;
}

.hero-eyebrow-text {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 3px;
    text-transform: uppercase;
    color: var(--color-muted);
}

.hero-rotating {
    display: flex;
    align-items: baseline;
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
    font-family: var(--font-heading);
    font-size: clamp(20px, 3vw, 24px);
    font-weight: 500;
    color: var(--color-muted);
}

.hero-rotating-prefix {
    font-weight: 400;
}

.hero-rotating-words {
    position: relative;
    height: 1.2em;
    overflow: hidden;
}

.hero-rotating-word {
    position: absolute;
    top: 0;
    left: 0;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.5s ease;
    color: var(--color-accent);
    font-weight: 600;
    white-space: nowrap;
}

.hero-rotating-word.active {
    opacity: 1;
    transform: translateY(0);
}

.hero-rotating-word.exit {
    opacity: 0;
    transform: translateY(-20px);
}

.hero-title {
    font-family: var(--font-heading);
    font-size: clamp(36px, 7vw, 56px);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: var(--space-xl);
}

.hero-title-line {
    display: block;
}

.hero-title-highlight {
    position: relative;
    display: inline-block;
}

.hero-title-highlight::after {
    content: '';
    position: absolute;
    bottom: 4px;
    left: 0;
    right: 0;
    height: 8px;
    background-color: var(--color-accent);
    opacity: 0.3;
    z-index: -1;
}

.hero-subtitle {
    font-size: 17px;
    color: var(--color-muted);
    margin-bottom: var(--space-xl);
    max-width: 480px;
}

.hero-cta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-md);
}

.hero-live-badge {
    position: fixed;
    bottom: var(--space-xl);
    left: var(--space-xl);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    z-index: 100;
}

.hero-live-dot {
    width: 8px;
    height: 8px;
    background-color: var(--color-success);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.7; transform: scale(1.1); }
}

.hero-live-text {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--color-muted);
}

.hero-live-text strong {
    color: var(--color-ink);
    font-weight: 500;
}

.hero-scroll {
    position: absolute;
    bottom: var(--space-xl);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
    animation: fadeInOut 2s ease-in-out infinite;
}

@keyframes fadeInOut {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 0.8; }
}

.hero-scroll-line {
    width: 1px;
    height: 40px;
    background: linear-gradient(to bottom, var(--color-border-dark), transparent);
}

.hero-scroll-text {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 2px;
    color: var(--color-muted);
}

@media (max-width: 768px) {
    .hero-live-badge {
        position: relative;
        bottom: auto;
        left: auto;
        margin-top: var(--space-xl);
        display: inline-flex;
    }

    .hero-scroll {
        display: none;
    }
}

/* ========================================
   Trust Bar Section
   ======================================== */

.trust-bar {
    background-color: var(--color-ink);
    padding: var(--space-2xl) 0;
}

.trust-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.trust-value {
    display: flex;
    align-items: baseline;
    justify-content: center;
}

.trust-number {
    font-family: var(--font-heading);
    font-size: clamp(28px, 5vw, 38px);
    font-weight: 700;
    color: white;
}

.trust-suffix {
    font-family: var(--font-mono);
    font-size: 14px;
    color: rgba(255, 255, 255, 0.5);
    margin-left: 2px;
}

.trust-label {
    font-family: var(--font-mono);
    font-size: 12px;
    color: rgba(255, 255, 255, 0.45);
    margin-top: var(--space-xs);
}

.trust-divider {
    width: 1px;
    height: 48px;
    background-color: rgba(255, 255, 255, 0.1);
}

@media (max-width: 768px) {
    .trust-container {
        flex-wrap: wrap;
        gap: var(--space-xl);
        justify-content: center;
    }

    .trust-divider {
        display: none;
    }

    .trust-item {
        flex: 1 1 40%;
    }
}

/* ========================================
   Courses Section
   ======================================== */

.courses {
    padding: var(--space-4xl) 0;
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
}

.course-card {
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    padding: var(--space-xl);
    transition: all var(--transition-base);
}

.course-card:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-md);
}

.course-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-md);
}

.course-level {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--color-accent);
}

.course-duration {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--color-muted);
}

.course-name {
    font-family: var(--font-heading);
    font-size: 24px;
    color: var(--color-ink);
    margin-bottom: var(--space-xs);
}

.course-name-en {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--color-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    display: block;
    margin-bottom: var(--space-md);
}

.course-outcome {
    font-size: 14px;
    color: var(--color-ink-2);
    margin-bottom: var(--space-lg);
    line-height: 1.6;
}

.course-price {
    margin-bottom: var(--space-lg);
}

.course-price-value {
    font-family: var(--font-mono);
    font-size: 20px;
    font-weight: 500;
    color: var(--color-ink);
}

.course-price-detail {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--color-muted);
    margin-left: var(--space-sm);
}

.course-toggle {
    display: none;
}

.course-curriculum {
    margin-bottom: var(--space-lg);
    padding-top: var(--space-md);
    border-top: 1px solid var(--color-border);
}

.course-week {
    display: flex;
    gap: var(--space-md);
    padding: var(--space-sm) 0;
    border-bottom: 1px solid var(--color-border);
}

.course-week:last-child {
    border-bottom: none;
}

.course-week-label {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--color-accent);
    min-width: 60px;
}

.course-week-content {
    font-size: 13px;
    color: var(--color-ink-2);
}

.course-btn {
    width: 100%;
}

/* Package Card */
.package-card {
    background-color: var(--color-ink);
    padding: var(--space-2xl);
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: var(--space-xl);
    align-items: center;
    position: relative;
    overflow: hidden;
}

.package-watermark {
    position: absolute;
    left: var(--space-xl);
    top: 50%;
    transform: translateY(-50%);
    font-family: var(--font-heading);
    font-size: 120px;
    font-weight: 800;
    color: rgba(255, 255, 255, 0.04);
    pointer-events: none;
}

.package-content {
    position: relative;
    z-index: 1;
}

.package-badge {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 9px;
    letter-spacing: 2px;
    color: var(--color-accent);
    background-color: var(--color-accent-light);
    padding: 4px 10px;
    margin-bottom: var(--space-md);
}

.package-name {
    font-family: var(--font-heading);
    font-size: 28px;
    color: white;
    margin-bottom: var(--space-xs);
}

.package-name-en {
    font-family: var(--font-mono);
    font-size: 11px;
    color: rgba(255, 255, 255, 0.45);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.package-desc {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.6);
    margin-top: var(--space-md);
    max-width: 400px;
}

.package-pricing {
    text-align: right;
    position: relative;
    z-index: 1;
}

.package-original {
    font-family: var(--font-mono);
    font-size: 14px;
    color: rgba(255, 255, 255, 0.4);
    text-decoration: line-through;
    display: block;
}

.package-price {
    font-family: var(--font-mono);
    font-size: 28px;
    font-weight: 500;
    color: white;
    display: block;
    margin: var(--space-xs) 0;
}

.package-discount {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.5px;
    color: var(--color-price);
    background-color: var(--color-price-light);
    padding: 4px 10px;
}

.package-btn {
    position: relative;
    z-index: 1;
}

@media (max-width: 900px) {
    .courses-grid {
        grid-template-columns: 1fr;
    }

    .package-card {
        grid-template-columns: 1fr;
        text-align: center;
    }

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

    .package-desc {
        max-width: none;
    }
}

/* ========================================
   Demo Section
   ======================================== */

.demo {
    padding: var(--space-4xl) 0;
    background-color: var(--color-surface);
}

.demo-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
    align-items: start;
}

.demo-info {
    position: sticky;
    top: calc(var(--nav-height) + var(--space-xl));
}

.demo-desc {
    font-size: 16px;
    color: var(--color-ink-2);
    margin-bottom: var(--space-xl);
    line-height: 1.8;
}

.demo-features {
    list-style: none;
}

.demo-feature {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-sm) 0;
    font-size: 14px;
    color: var(--color-ink-2);
}

.demo-feature-icon {
    color: var(--color-success);
    flex-shrink: 0;
}

.demo-playground {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.demo-input-area {
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    padding: var(--space-lg);
}

.demo-label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--color-ink);
    margin-bottom: var(--space-sm);
}

.demo-textarea {
    width: 100%;
    min-height: 100px;
    padding: var(--space-md);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-family: var(--font-sans);
    font-size: 14px;
    color: var(--color-ink);
    resize: vertical;
    margin-bottom: var(--space-md);
}

.demo-textarea:focus {
    outline: none;
    border-color: var(--color-accent);
}

.demo-btn {
    width: 100%;
}

.demo-output-area {
    background-color: #0d0d0d;
    border-radius: var(--radius-md);
    overflow: hidden;
}

.demo-output-header {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-lg);
    background-color: #1a1a1a;
    border-bottom: 1px solid #2a2a2a;
}

.demo-output-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: #3a3a3a;
}

.demo-output-dot:nth-child(1) { background-color: #ff5f56; }
.demo-output-dot:nth-child(2) { background-color: #ffbd2e; }
.demo-output-dot:nth-child(3) { background-color: #27ca40; }

.demo-output-title {
    font-family: var(--font-mono);
    font-size: 12px;
    color: #666;
    margin-left: var(--space-md);
}

.demo-output-code {
    padding: var(--space-lg);
    min-height: 300px;
    max-height: 500px;
    overflow-y: auto;
    font-family: var(--font-mono);
    font-size: 13px;
    line-height: 1.6;
    color: #e0e0e0;
}

.demo-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 200px;
    gap: var(--space-md);
    color: #555;
}

.demo-placeholder svg {
    opacity: 0.5;
}

.demo-typing-cursor {
    display: inline-block;
    width: 2px;
    height: 1em;
    background-color: var(--color-accent);
    animation: blink 1s step-end infinite;
}

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

.demo-cta {
    text-align: center;
    padding: var(--space-md);
    background-color: var(--color-accent-light);
    border-radius: var(--radius-sm);
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.demo-cta span {
    font-size: 14px;
    color: var(--color-ink-2);
}

.demo-cta-link {
    font-weight: 500;
    color: var(--color-accent);
    margin-left: var(--space-sm);
}

.demo-cta-link:hover {
    text-decoration: underline;
}

@media (max-width: 900px) {
    .demo-grid {
        grid-template-columns: 1fr;
    }

    .demo-info {
        position: static;
    }
}

/* ========================================
   Quiz Section
   ======================================== */

.quiz {
    padding: var(--space-4xl) 0;
}

.quiz-intro {
    text-align: center;
    max-width: 540px;
    margin: 0 auto;
}

.quiz-start-btn {
    margin-top: var(--space-xl);
}

.quiz-questions {
    max-width: 640px;
    margin: 0 auto;
}

.quiz-progress {
    height: 4px;
    background-color: var(--color-border);
    border-radius: 2px;
    margin-bottom: var(--space-2xl);
    overflow: hidden;
}

.quiz-progress-bar {
    height: 100%;
    background-color: var(--color-accent);
    transition: width var(--transition-base);
    width: 0;
}

.quiz-question {
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from { opacity: 0; transform: translateX(20px); }
    to { opacity: 1; transform: translateX(0); }
}

.quiz-question-number {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--color-accent);
    letter-spacing: 2px;
    margin-bottom: var(--space-md);
}

.quiz-question-text {
    font-family: var(--font-heading);
    font-size: 24px;
    color: var(--color-ink);
    margin-bottom: var(--space-xl);
    line-height: 1.4;
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.quiz-option {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-lg);
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    text-align: left;
    width: 100%;
}

.quiz-option:hover {
    border-color: var(--color-accent);
}

.quiz-option.selected {
    border-color: var(--color-accent);
    background-color: var(--color-accent-light);
}

.quiz-option-radio {
    width: 20px;
    height: 20px;
    border: 2px solid var(--color-border-dark);
    border-radius: 50%;
    flex-shrink: 0;
    position: relative;
}

.quiz-option.selected .quiz-option-radio {
    border-color: var(--color-accent);
}

.quiz-option.selected .quiz-option-radio::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 10px;
    height: 10px;
    background-color: var(--color-accent);
    border-radius: 50%;
}

.quiz-option-text {
    font-size: 14px;
    color: var(--color-ink-2);
}

/* Quiz Result */
.quiz-result {
    text-align: center;
    max-width: 640px;
    margin: 0 auto;
    animation: fadeIn 0.5s ease;
}

.quiz-result-badge {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 2px;
    color: var(--color-accent);
    background-color: var(--color-accent-light);
    padding: var(--space-sm) var(--space-lg);
    margin-bottom: var(--space-lg);
}

.quiz-result-type {
    font-family: var(--font-heading);
    font-size: clamp(36px, 6vw, 48px);
    color: var(--color-ink);
    margin-bottom: var(--space-md);
}

.quiz-result-tool {
    font-family: var(--font-mono);
    font-size: 14px;
    color: var(--color-accent);
    margin-bottom: var(--space-xl);
}

.quiz-result-desc {
    font-size: 16px;
    color: var(--color-ink-2);
    line-height: 1.8;
    margin-bottom: var(--space-xl);
}

.quiz-result-course {
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--color-muted);
    padding: var(--space-md);
    background-color: var(--color-bg);
    margin-bottom: var(--space-xl);
}

.quiz-result-actions {
    display: flex;
    justify-content: center;
    gap: var(--space-md);
    flex-wrap: wrap;
}

/* ========================================
   Gallery Section
   ======================================== */

.gallery {
    padding: var(--space-4xl) 0;
    background-color: var(--color-surface);
    overflow: hidden;
}

.gallery-scroll {
    margin-top: var(--space-xl);
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
    cursor: grab;
}

.gallery-scroll::-webkit-scrollbar {
    display: none;
}

.gallery-scroll:active {
    cursor: grabbing;
}

.gallery-track {
    display: flex;
    gap: var(--space-lg);
    padding: var(--space-md) var(--space-xl);
    width: max-content;
}

.gallery-item {
    width: 320px;
    flex-shrink: 0;
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    overflow: hidden;
    transition: all var(--transition-base);
}

.gallery-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.gallery-image {
    height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.gallery-info {
    padding: var(--space-lg);
}

.gallery-title {
    font-size: 15px;
    font-weight: 500;
    color: var(--color-ink);
    margin-bottom: var(--space-xs);
}

.gallery-author {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--color-muted);
}

/* ========================================
   Reviews Section
   ======================================== */

.reviews {
    padding: var(--space-4xl) 0;
}

.reviews-slider {
    max-width: 720px;
    margin: 0 auto;
    position: relative;
}

.reviews-track {
    position: relative;
    min-height: 280px;
}

.review-card {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    padding: var(--space-2xl);
    text-align: center;
    opacity: 0;
    visibility: hidden;
    transform: translateX(20px);
    transition: all var(--transition-base);
}

.review-card.active {
    opacity: 1;
    visibility: visible;
    transform: translateX(0);
}

.review-rating {
    display: flex;
    justify-content: center;
    gap: 4px;
    margin-bottom: var(--space-lg);
}

.review-star {
    color: #fbbf24;
}

.review-content {
    font-family: var(--font-sans);
    font-size: 18px;
    font-weight: 400;
    line-height: 1.7;
    color: var(--color-ink);
    margin-bottom: var(--space-xl);
}

.review-author {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.review-name {
    font-weight: 500;
    color: var(--color-ink);
}

.review-course {
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--color-muted);
}

.reviews-nav {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--space-lg);
    margin-top: var(--space-xl);
}

.reviews-prev,
.reviews-next {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--color-border);
    border-radius: 50%;
    color: var(--color-muted);
    transition: all var(--transition-fast);
}

.reviews-prev:hover,
.reviews-next:hover {
    border-color: var(--color-ink);
    color: var(--color-ink);
}

.reviews-dots {
    display: flex;
    gap: var(--space-sm);
}

.reviews-dot {
    width: 8px;
    height: 8px;
    background-color: var(--color-border);
    border-radius: 50%;
    transition: all var(--transition-fast);
}

.reviews-dot.active {
    background-color: var(--color-ink);
    transform: scale(1.2);
}

/* ========================================
   FAQ Section
   ======================================== */

.faq {
    padding: var(--space-4xl) 0;
    background-color: var(--color-surface);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid var(--color-border);
}

.faq-item:first-child {
    border-top: 1px solid var(--color-border);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-lg);
    padding: var(--space-lg) 0;
    text-align: left;
    transition: color var(--transition-fast);
}

.faq-question:hover {
    color: var(--color-accent);
}

.faq-question-text {
    font-size: 15px;
    font-weight: 500;
}

.faq-icon {
    flex-shrink: 0;
    color: var(--color-muted);
    transition: transform var(--transition-base);
}

.faq-question[aria-expanded="true"] .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-slow);
}

.faq-answer.open {
    max-height: 500px;
}

.faq-answer p {
    font-size: 14px;
    color: var(--color-ink-2);
    line-height: 1.8;
    padding-bottom: var(--space-lg);
}

/* ========================================
   Contact Section
   ======================================== */

.contact {
    padding: var(--space-4xl) 0;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
    align-items: start;
}

.contact-desc {
    font-size: 16px;
    color: var(--color-ink-2);
    line-height: 1.8;
    margin-bottom: var(--space-xl);
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}

.contact-method {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    font-family: var(--font-mono);
    font-size: 14px;
    color: var(--color-ink-2);
    transition: color var(--transition-fast);
}

.contact-method:hover {
    color: var(--color-accent);
}

.contact-method-icon {
    color: var(--color-accent);
}

.contact-form-container {
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    padding: var(--space-xl);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.form-label {
    font-size: 13px;
    font-weight: 500;
    color: var(--color-ink);
}

.form-input,
.form-select,
.form-textarea {
    padding: var(--space-md);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-family: var(--font-sans);
    font-size: 14px;
    color: var(--color-ink);
    background-color: var(--color-bg);
    transition: border-color var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--color-accent);
}

.form-select {
    cursor: pointer;
}

.form-textarea {
    resize: vertical;
    min-height: 80px;
}

.form-submit {
    margin-top: var(--space-md);
    width: 100%;
}

.form-notice {
    font-size: 12px;
    color: var(--color-muted);
    text-align: center;
    margin-top: var(--space-md);
}

@media (max-width: 900px) {
    .contact-grid {
        grid-template-columns: 1fr;
    }
}

/* ========================================
   Footer
   ======================================== */

.footer {
    background-color: var(--color-ink);
    color: rgba(255, 255, 255, 0.6);
    padding: var(--space-3xl) 0 var(--space-xl);
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-xl);
}

.footer-main {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--space-3xl);
    padding-bottom: var(--space-2xl);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-logo {
    font-family: var(--font-heading);
    font-size: 20px;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: var(--space-md);
}

.footer-tagline {
    font-size: 13px;
    color: rgba(255, 255, 255, 0.4);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-xl);
}

.footer-col-title {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.4);
    margin-bottom: var(--space-md);
}

.footer-link {
    display: block;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.6);
    padding: var(--space-xs) 0;
    transition: color var(--transition-fast);
}

.footer-link:hover {
    color: white;
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: var(--space-xl);
    flex-wrap: wrap;
    gap: var(--space-md);
}

.footer-copyright {
    font-size: 12px;
    color: rgba(255, 255, 255, 0.3);
}

.footer-legal {
    display: flex;
    gap: var(--space-lg);
}

.footer-legal-link {
    font-size: 12px;
    color: rgba(255, 255, 255, 0.3);
    transition: color var(--transition-fast);
}

.footer-legal-link:hover {
    color: rgba(255, 255, 255, 0.6);
}

@media (max-width: 768px) {
    .footer-main {
        grid-template-columns: 1fr;
    }

    .footer-links {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
}

/* ========================================
   Toast Notification
   ======================================== */

.toast {
    position: fixed;
    bottom: var(--space-xl);
    right: var(--space-xl);
    background-color: var(--color-ink);
    color: white;
    padding: var(--space-md) var(--space-lg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-base);
}

.toast.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.toast-content {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.toast-icon {
    color: var(--color-success);
}

.toast-message {
    font-size: 14px;
}

/* ========================================
   Utility Classes
   ======================================== */

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Code syntax highlighting */
.code-keyword { color: #93c5fd; }
.code-string { color: #a7f3d0; }
.code-comment { color: #6b7280; }
.code-function { color: #fde68a; }
.code-variable { color: #f9a8d4; }
.code-number { color: #fdba74; }