/* ========================================
   Course 3: 知識系統 × 輸出引擎
   Target: 知識囤積型 + 工具控
   Style: Dark mode, Structured, Professional depth
   ======================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Noto+Sans+TC:wght@400;500;700&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
    /* Dark Mode Base */
    --bg-dark: #0f0f1a;
    --bg-card: #1a1a2e;
    --bg-elevated: #252542;

    /* Accent: Bright Cyan/Green (Growth, Tech) */
    --accent: #00d9a5;
    --accent-light: #4ff5c9;
    --accent-dark: #00b386;

    /* Secondary: Electric Blue */
    --secondary: #5c7cfa;
    --secondary-light: #8fa4ff;

    /* Text */
    --text-bright: #ffffff;
    --text-primary: #e4e4ed;
    --text-muted: #9999b3;
    --text-dim: #666680;

    /* Functional */
    --success: #00d9a5;
    --warning: #ffc107;
    --border: #2d2d4a;

    /* Shadows */
    --shadow-glow: 0 0 40px rgba(0, 217, 165, 0.15);
    --shadow-card: 0 4px 30px rgba(0, 0, 0, 0.4);
}

body {
    background: var(--bg-dark);
    color: var(--text-primary);
}

/* =============== HERO SECTION =============== */
.hero {
    background: var(--bg-dark);
    padding: 6rem 0 5rem;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -20%;
    width: 80%;
    height: 200%;
    background: radial-gradient(ellipse, rgba(0, 217, 165, 0.08) 0%, transparent 60%);
    pointer-events: none;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    right: -10%;
    width: 60%;
    height: 150%;
    background: radial-gradient(ellipse, rgba(92, 124, 250, 0.06) 0%, transparent 60%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
}

.hero-badge {
    display: inline-block;
    background: var(--bg-elevated);
    border: 1px solid var(--accent);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--accent);
    margin-bottom: 1.5rem;
    font-family: 'JetBrains Mono', monospace;
}

.hero h1 {
    font-size: clamp(2rem, 5vw, 3.25rem);
    font-weight: 700;
    line-height: 1.25;
    margin-bottom: 1.5rem;
    color: var(--text-bright);
}

.hero h1 span {
    color: var(--accent);
}

.hero h1 .strike {
    text-decoration: line-through;
    color: var(--text-muted);
    opacity: 0.6;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
    max-width: 600px;
    line-height: 1.75;
}

.hero-cta-group {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn-primary {
    background: var(--accent);
    color: var(--bg-dark);
    font-size: 1rem;
    font-weight: 600;
    padding: 1rem 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
    background: var(--accent-light);
    box-shadow: 0 0 60px rgba(0, 217, 165, 0.25);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    font-size: 1rem;
    padding: 1rem 2rem;
    border-radius: 8px;
    border: 1px solid var(--border);
}

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

.hero-stats {
    display: flex;
    gap: 3rem;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
}

.stat-item {
    text-align: left;
}

.stat-number {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--accent);
    font-family: 'JetBrains Mono', monospace;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* =============== PROBLEM SECTION =============== */
.problem-section {
    padding: 5rem 0;
    background: var(--bg-card);
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 3rem;
}

.section-header h2 {
    color: var(--text-bright);
    font-size: clamp(1.5rem, 3.5vw, 2rem);
    margin-bottom: 1rem;
}

.section-header h2 span {
    color: var(--accent);
}

.section-header p {
    color: var(--text-muted);
    font-size: 1.0625rem;
}

.problem-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    max-width: 1000px;
    margin: 0 auto;
}

.problem-card {
    background: var(--bg-elevated);
    border-radius: 12px;
    padding: 1.75rem;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
}

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

.problem-card .icon {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.problem-card h3 {
    color: var(--text-bright);
    font-size: 1.125rem;
    margin-bottom: 0.75rem;
}

.problem-card p {
    color: var(--text-muted);
    font-size: 0.9375rem;
    line-height: 1.65;
}

.problem-card .tried {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
    font-size: 0.8125rem;
    color: var(--text-dim);
    font-family: 'JetBrains Mono', monospace;
}

/* =============== FRAMEWORK SECTION =============== */
.framework-section {
    padding: 5rem 0;
    background: var(--bg-dark);
}

.framework-intro {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 4rem;
}

.framework-intro h2 span {
    color: var(--accent);
}

.framework-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.framework-card {
    background: var(--bg-card);
    border-radius: 16px;
    padding: 2rem;
    border: 1px solid var(--border);
    text-align: center;
    transition: all 0.3s ease;
    position: relative;
}

.framework-card::before {
    content: '';
    position: absolute;
    inset: -1px;
    background: linear-gradient(135deg, var(--accent), var(--secondary));
    border-radius: 17px;
    z-index: -1;
    opacity: 0;
    transition: opacity 0.3s ease;
}

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

.framework-card:hover {
    background: var(--bg-elevated);
}

.framework-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--accent), var(--secondary));
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    margin: 0 auto 1.5rem;
}

.framework-card h3 {
    color: var(--text-bright);
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.framework-card .tag {
    display: inline-block;
    background: rgba(0, 217, 165, 0.15);
    color: var(--accent);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.25rem 0.75rem;
    border-radius: 50px;
    margin-bottom: 1rem;
    font-family: 'JetBrains Mono', monospace;
}

.framework-card p {
    color: var(--text-muted);
    font-size: 0.9375rem;
    line-height: 1.65;
}

/* =============== COURSE MODULES =============== */
.modules-section {
    padding: 5rem 0;
    background: var(--bg-card);
}

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

.module-item {
    display: flex;
    gap: 1.5rem;
    padding: 2rem;
    background: var(--bg-dark);
    border-radius: 16px;
    margin-bottom: 1.5rem;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
}

.module-item:hover {
    border-color: var(--accent);
    box-shadow: var(--shadow-glow);
}

.module-number {
    width: 48px;
    height: 48px;
    background: var(--accent);
    color: var(--bg-dark);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.25rem;
    flex-shrink: 0;
    font-family: 'JetBrains Mono', monospace;
}

.module-content h3 {
    color: var(--text-bright);
    font-size: 1.125rem;
    margin-bottom: 0.5rem;
}

.module-content p {
    color: var(--text-muted);
    font-size: 0.9375rem;
    line-height: 1.65;
    margin-bottom: 1rem;
}

.module-topics {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.module-topics span {
    background: var(--bg-elevated);
    color: var(--text-muted);
    font-size: 0.75rem;
    padding: 0.375rem 0.75rem;
    border-radius: 6px;
    border: 1px solid var(--border);
    font-family: 'JetBrains Mono', monospace;
}

/* =============== WHO IS THIS FOR =============== */
.audience-section {
    padding: 5rem 0;
    background: var(--bg-dark);
}

.audience-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.audience-card {
    background: var(--bg-card);
    border-radius: 16px;
    padding: 2rem;
    border: 1px solid var(--border);
}

.audience-card.yes {
    border-color: var(--accent);
}

.audience-card.no {
    border-color: var(--warning);
}

.audience-card h3 {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.125rem;
    margin-bottom: 1.5rem;
}

.audience-card.yes h3 {
    color: var(--accent);
}

.audience-card.no h3 {
    color: var(--warning);
}

.audience-card ul {
    list-style: none;
}

.audience-card li {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
    color: var(--text-muted);
    font-size: 0.9375rem;
}

.audience-card.yes li::before {
    content: '✓';
    color: var(--accent);
}

.audience-card.no li::before {
    content: '✕';
    color: var(--warning);
}

/* =============== TESTIMONIALS =============== */
.testimonial-section {
    padding: 5rem 0;
    background: var(--bg-card);
}

.testimonial-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.testimonial-card {
    background: var(--bg-dark);
    border-radius: 16px;
    padding: 2rem;
    border: 1px solid var(--border);
}

.testimonial-content {
    font-size: 0.9375rem;
    line-height: 1.75;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.author-avatar {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--accent), var(--secondary));
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
}

.author-info h4 {
    color: var(--text-bright);
    font-size: 0.9375rem;
}

.author-info p {
    color: var(--text-muted);
    font-size: 0.8125rem;
    font-family: 'JetBrains Mono', monospace;
}

/* =============== PRICING =============== */
.pricing-section {
    padding: 5rem 0;
    background: var(--bg-dark);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.pricing-card {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 2.5rem;
    border: 1px solid var(--border);
    position: relative;
}

.pricing-card.featured {
    border-color: var(--accent);
    box-shadow: var(--shadow-glow);
}

.pricing-card.featured::before {
    content: 'RECOMMENDED';
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--accent);
    color: var(--bg-dark);
    font-size: 0.6875rem;
    font-weight: 700;
    padding: 0.375rem 1rem;
    border-radius: 50px;
    font-family: 'JetBrains Mono', monospace;
}

.pricing-header {
    text-align: center;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border);
}

.pricing-header h3 {
    color: var(--text-bright);
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.pricing-header .price {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--accent);
    font-family: 'JetBrains Mono', monospace;
}

.pricing-header .price span {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 400;
}

.pricing-features {
    list-style: none;
    margin-bottom: 2rem;
}

.pricing-features li {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.625rem 0;
    color: var(--text-muted);
    font-size: 0.875rem;
}

.pricing-features .check {
    color: var(--accent);
}

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

.pricing-cta .btn-primary {
    width: 100%;
}

.pricing-card:not(.featured) .pricing-cta .btn-primary {
    background: var(--bg-elevated);
    color: var(--text-primary);
    box-shadow: none;
    border: 1px solid var(--border);
}

.pricing-card:not(.featured) .pricing-cta .btn-primary:hover {
    border-color: var(--accent);
    color: var(--accent);
}

/* =============== FAQ =============== */
.faq-section {
    padding: 5rem 0;
    background: var(--bg-card);
}

.faq-list {
    max-width: 700px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-dark);
    border-radius: 12px;
    margin-bottom: 1rem;
    border: 1px solid var(--border);
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 1.25rem 1.5rem;
    background: none;
    border: none;
    text-align: left;
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-bright);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: color 0.3s ease;
}

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

.faq-question .icon {
    font-size: 1.25rem;
    color: var(--accent);
    transition: transform 0.3s ease;
    font-family: 'JetBrains Mono', monospace;
}

.faq-item.active .faq-question .icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 300px;
}

.faq-answer-content {
    padding: 0 1.5rem 1.5rem;
    color: var(--text-muted);
    font-size: 0.9375rem;
    line-height: 1.7;
}

/* =============== FOOTER CTA =============== */
.footer-cta {
    padding: 5rem 0;
    background: linear-gradient(135deg, var(--bg-elevated) 0%, var(--bg-dark) 100%);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.footer-cta::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent), transparent);
}

.footer-cta h2 {
    color: var(--text-bright);
    margin-bottom: 1rem;
}

.footer-cta p {
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto 2rem;
}

.footer-cta .btn-primary {
    background: var(--accent);
    color: var(--bg-dark);
    font-size: 1.125rem;
    padding: 1.125rem 3rem;
}

/* =============== RESPONSIVE =============== */
@media (max-width: 1024px) {

    .problem-grid,
    .framework-grid,
    .testimonial-grid {
        grid-template-columns: 1fr;
        max-width: 600px;
    }
}

@media (max-width: 768px) {
    .hero {
        padding: 4rem 0;
    }

    .hero-stats {
        flex-direction: column;
        gap: 1.5rem;
    }

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

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

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

    .module-item {
        flex-direction: column;
    }
}