/* ========================================
   Van Klassieke naar Organische Strategie
   Tutorial Stylesheet
   ======================================== */

/* CSS Variables */
:root {
    --color-bg-light: #ecf0f1;
    --color-bg-dark: #2c3e50;
    --color-primary: #3498db;
    --color-secondary: #f1c40f;
    --color-accent: #e74c3c;
    --color-success: #27ae60;
    --color-text-dark: #2c3e50;
    --color-text-light: #ecf0f1;
    --color-text-muted: #5a6c7d;
    --color-text-muted-light: #b8c6cc;
    --font-heading: 'Segoe UI', system-ui, sans-serif;
    --font-body: 'Segoe UI', system-ui, sans-serif;
    --transition-fast: 0.2s ease;
    --transition-medium: 0.3s ease;
    --shadow-soft: 0 2px 10px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 20px rgba(0, 0, 0, 0.15);
    --shadow-strong: 0 8px 30px rgba(0, 0, 0, 0.2);
    --radius-small: 4px;
    --radius-medium: 8px;
    --radius-large: 16px;
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    padding: 0;
    font-family: var(--font-body);
    font-size: 18px;
    line-height: 1.7;
    color: var(--color-text-dark);
    background-color: var(--color-bg-light);
}

/* Typography */
h1, h2, h3, h4 {
    font-family: var(--font-heading);
    font-weight: 600;
    line-height: 1.3;
    margin-top: 0;
}

h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
}

h2 {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    margin-bottom: 1rem;
}

h3 {
    font-size: clamp(1.25rem, 3vw, 1.75rem);
    margin-bottom: 0.75rem;
}

h4 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

p {
    margin-top: 0;
    margin-bottom: 1rem;
}

/* Container */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Progress Bar */
.progress-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: rgba(0, 0, 0, 0.1);
    z-index: 1000;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    width: 0%;
    transition: width 0.1s linear;
}

/* Navigation Dots */
.nav-dots {
    position: fixed;
    right: 2rem;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    flex-direction: column;
    gap: 1rem;
    z-index: 100;
}

.nav-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.2);
    border: 2px solid transparent;
    transition: var(--transition-fast);
    cursor: pointer;
}

.nav-dot:hover {
    background: var(--color-primary);
    transform: scale(1.2);
}

.nav-dot.active {
    background: var(--color-primary);
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px rgba(52, 152, 219, 0.3);
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--color-bg-dark) 0%, #34495e 100%);
    color: var(--color-text-light);
    text-align: center;
    padding: 2rem;
}

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

.hero h1 {
    margin-bottom: 1rem;
    background: linear-gradient(90deg, var(--color-text-light), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    font-size: 1.25rem;
    color: var(--color-text-muted);
    margin-bottom: 2rem;
}

.cta-button {
    display: inline-block;
    padding: 1rem 2.5rem;
    background: var(--color-primary);
    color: white;
    text-decoration: none;
    border-radius: var(--radius-large);
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition-medium);
    box-shadow: var(--shadow-medium);
}

.cta-button:hover {
    background: #2980b9;
    transform: translateY(-2px);
    box-shadow: var(--shadow-strong);
}

/* Sections */
.section {
    min-height: 100vh;
    padding: 6rem 0;
    position: relative;
}

.section-light {
    background: var(--color-bg-light);
    color: var(--color-text-dark);
}

.section-dark {
    background: var(--color-bg-dark);
    color: var(--color-text-light);
}

.section-number {
    position: absolute;
    top: 2rem;
    left: 2rem;
    font-size: 4rem;
    font-weight: 700;
    opacity: 0.1;
    line-height: 1;
}

.intro {
    font-size: 1.2rem;
    color: inherit;
    opacity: 0.9;
    max-width: 700px;
    margin-bottom: 3rem;
}

.section-dark .intro {
    color: var(--color-text-muted-light);
}

.source-link {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    margin-bottom: 2rem;
    padding: 0.75rem 1rem;
    background: var(--color-bg-light);
    border-radius: var(--radius-small);
    border-left: 3px solid var(--color-primary);
}

.source-link a {
    color: var(--color-primary);
    text-decoration: none;
}

.source-link a:hover {
    text-decoration: underline;
}

/* Video Container */
.video-container {
    margin: 2rem 0 3rem;
    border-radius: var(--radius-large);
    overflow: hidden;
    box-shadow: var(--shadow-strong);
}

.video-container video {
    width: 100%;
    display: block;
}

/* Concept Cards */
.concept-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.concept-card {
    background: white;
    padding: 2rem;
    border-radius: var(--radius-large);
    text-align: center;
    box-shadow: var(--shadow-soft);
    transition: var(--transition-medium);
    cursor: pointer;
    position: relative;
}

.concept-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-strong);
}

.concept-card:hover .tooltip {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.card-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.concept-card h3 {
    color: var(--color-primary);
    margin-bottom: 0.5rem;
}

.concept-card p {
    color: var(--color-text-muted);
    margin: 0;
}

/* Tooltip */
.tooltip {
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(10px);
    background: var(--color-bg-dark);
    color: var(--color-text-light);
    padding: 1.5rem;
    border-radius: var(--radius-medium);
    width: 300px;
    font-size: 0.9rem;
    line-height: 1.5;
    text-align: left;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-medium);
    z-index: 10;
    box-shadow: var(--shadow-strong);
}

.tooltip::after {
    content: '';
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    border: 10px solid transparent;
    border-top-color: var(--color-bg-dark);
}

/* Info Box */
.info-box {
    background: white;
    padding: 2rem;
    border-radius: var(--radius-large);
    margin: 2rem 0;
    border-left: 4px solid var(--color-primary);
}

.section-dark .info-box {
    background: rgba(255, 255, 255, 0.1);
}

.info-box h4 {
    color: var(--color-primary);
    margin-bottom: 1rem;
}

.info-box-highlight {
    background: linear-gradient(135deg, rgba(52, 152, 219, 0.1), rgba(241, 196, 15, 0.1));
    border-left-color: var(--color-secondary);
}

/* Linear Flow */
.linear-flow {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1.5rem;
}

.flow-item {
    background: var(--color-primary);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-small);
    font-weight: 600;
}

.flow-arrow {
    font-size: 1.5rem;
    color: var(--color-text-muted);
}

/* VUCA Section */
.vuca-container {
    margin: 3rem 0;
}

.vuca-container h3 {
    text-align: center;
    margin-bottom: 2rem;
}

.vuca-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

/* VUCA Flip Card Container */
.vuca-item {
    perspective: 1000px;
    height: 160px;
    cursor: pointer;
}

.vuca-item .card-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

.vuca-item:hover .card-inner {
    transform: rotateY(180deg);
}

.vuca-item .card-front,
.vuca-item .card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    border-radius: var(--radius-large);
    padding: 1.5rem;
    display: flex;
    gap: 1rem;
}

.vuca-item .card-front {
    background: rgba(255, 255, 255, 0.1);
}

.vuca-item .card-back {
    background: var(--color-bg-dark);
    transform: rotateY(180deg);
    flex-direction: column;
    justify-content: center;
    color: var(--color-text-light);
    font-size: 0.95rem;
    line-height: 1.6;
}

.vuca-letter {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-secondary);
    line-height: 1;
}

.vuca-content h4 {
    color: var(--color-text-light);
    margin-bottom: 0.25rem;
}

.vuca-content p {
    color: var(--color-text-muted-light);
    font-size: 0.9rem;
    margin: 0;
}

/* Challenge Box */
.challenge-box {
    background: rgba(231, 76, 60, 0.1);
    border: 2px solid rgba(231, 76, 60, 0.3);
    padding: 2rem;
    border-radius: var(--radius-large);
    margin-top: 3rem;
}

.challenge-box h4 {
    color: #f5a89a;
    margin-bottom: 1.5rem;
}

.challenge-points {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.challenge-point {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
}

.point-icon {
    font-size: 1.5rem;
}

.challenge-point {
    color: var(--color-text-muted-light);
}

.challenge-point strong {
    color: var(--color-text-light);
}

.challenge-conclusion {
    margin-top: 1.5rem;
    padding-top: 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text-muted-light);
    text-align: center;
}

/* Strategy Steps */
.strategy-steps {
    margin: 3rem 0;
}

.strategy-steps h3 {
    text-align: center;
    margin-bottom: 2rem;
}

.strategy-step {
    display: flex;
    gap: 1.5rem;
    margin-bottom: 2rem;
    padding: 2rem;
    background: white;
    border-radius: var(--radius-large);
    box-shadow: var(--shadow-soft);
    transition: var(--transition-medium);
}

.strategy-step:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow-medium);
}

.step-number {
    flex-shrink: 0;
    width: 50px;
    height: 50px;
    background: var(--color-primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
}

.step-content h4 {
    color: var(--color-primary);
    margin-bottom: 0.5rem;
}

.step-example {
    margin-top: 1rem;
    padding: 1rem;
    background: var(--color-bg-light);
    border-radius: var(--radius-small);
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

/* Term Highlight */
.term {
    color: var(--color-primary);
    cursor: help;
    border-bottom: 1px dashed var(--color-primary);
    position: relative;
}

.term:hover::after {
    content: attr(data-definition);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    background: var(--color-bg-dark);
    color: var(--color-text-light);
    padding: 0.75rem 1rem;
    border-radius: var(--radius-small);
    font-size: 0.85rem;
    width: 250px;
    text-align: center;
    z-index: 10;
    box-shadow: var(--shadow-medium);
}

/* Feedback Loop */
.feedback-loop-container {
    margin: 3rem 0;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-large);
}

.feedback-loop {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: auto auto auto;
    gap: 1rem;
    max-width: 600px;
    margin: 0 auto;
    position: relative;
}

.loop-center {
    grid-column: 2;
    grid-row: 2;
    background: var(--color-primary);
    color: white;
    padding: 1.5rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    z-index: 2;
}

.loop-item {
    background: rgba(255, 255, 255, 0.1);
    padding: 1rem;
    border-radius: var(--radius-medium);
    text-align: center;
    transition: var(--transition-medium);
    cursor: pointer;
}

.loop-item:hover,
.loop-item.active {
    background: rgba(52, 152, 219, 0.3);
    transform: scale(1.05);
}

.loop-item-1 { grid-column: 2; grid-row: 1; }
.loop-item-2 { grid-column: 3; grid-row: 2; }
.loop-item-3 { grid-column: 2; grid-row: 3; }
.loop-item-4 { grid-column: 1; grid-row: 2; }

.loop-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.loop-label {
    font-weight: 600;
    color: var(--color-text-light);
}

.loop-description {
    font-size: 0.8rem;
    color: var(--color-text-muted-light);
    margin-top: 0.5rem;
    opacity: 0;
    transition: var(--transition-fast);
}

.loop-item:hover .loop-description,
.loop-item.active .loop-description {
    opacity: 1;
}

.loop-arrow {
    position: absolute;
    font-size: 1.5rem;
    color: var(--color-secondary);
    opacity: 0.5;
}

.loop-arrow-1 { top: 25%; right: 25%; transform: rotate(45deg); }
.loop-arrow-2 { bottom: 25%; right: 25%; transform: rotate(135deg); }
.loop-arrow-3 { bottom: 25%; left: 25%; transform: rotate(225deg); }
.loop-arrow-4 { top: 25%; left: 25%; transform: rotate(315deg); }

.loop-controls {
    text-align: center;
    margin-top: 2rem;
}

.loop-button {
    background: var(--color-secondary);
    color: var(--color-text-dark);
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-medium);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
}

.loop-button:hover {
    background: #f39c12;
    transform: scale(1.05);
}

/* Complexity Insights */
.complexity-insights {
    margin-top: 3rem;
}

.complexity-insights h3 {
    text-align: center;
    margin-bottom: 2rem;
}

.insight-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

.insight-card {
    background: rgba(255, 255, 255, 0.1);
    padding: 1.5rem;
    border-radius: var(--radius-large);
    text-align: center;
    transition: var(--transition-medium);
}

.insight-card:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-5px);
}

.insight-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.insight-card h4 {
    color: var(--color-secondary);
    margin-bottom: 0.5rem;
}

.insight-card p {
    color: var(--color-text-muted-light);
    font-size: 0.9rem;
    margin: 0;
}

/* Comparison Table */
.comparison-table-container {
    overflow-x: auto;
    margin: 2rem 0;
}

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: var(--radius-large);
    overflow: hidden;
    box-shadow: var(--shadow-medium);
}

.comparison-table th,
.comparison-table td {
    padding: 1rem 1.5rem;
    text-align: left;
    border-bottom: 1px solid var(--color-bg-light);
}

.comparison-table th {
    background: var(--color-bg-dark);
    color: var(--color-text-light);
    font-weight: 600;
}

.comparison-table th:first-child {
    background: transparent;
}

.comparison-table th:nth-child(2) {
    background: var(--color-primary);
}

.comparison-table th:nth-child(3) {
    background: var(--color-success);
}

.row-label {
    font-weight: 600;
    color: var(--color-text-muted);
    background: var(--color-bg-light);
}

.comparison-table tr:hover td:not(.row-label) {
    background: rgba(52, 152, 219, 0.05);
}

/* Summary Box */
.summary-box {
    background: linear-gradient(135deg, var(--color-primary), #2980b9);
    color: white;
    padding: 2.5rem;
    border-radius: var(--radius-large);
    margin: 3rem 0;
    text-align: center;
}

.summary-box h3 {
    margin-bottom: 1rem;
}

.summary-box p {
    font-size: 1.1rem;
    opacity: 0.95;
}

.summary-box .term {
    color: var(--color-secondary);
    border-bottom-color: var(--color-secondary);
}

.summary-box blockquote {
    margin: 2rem 0 0;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-medium);
    font-style: italic;
}

.summary-box cite {
    display: block;
    margin-top: 0.5rem;
    font-size: 0.9rem;
    opacity: 0.8;
}

/* Quiz Section */
.quiz-section {
    background: white;
    padding: 2rem;
    border-radius: var(--radius-large);
    margin: 3rem 0;
    box-shadow: var(--shadow-soft);
}

.quiz-section h3 {
    text-align: center;
    color: var(--color-primary);
    margin-bottom: 2rem;
}

.quiz-question {
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--color-bg-light);
}

.quiz-question:last-of-type {
    border-bottom: none;
}

.question-text {
    font-weight: 600;
    margin-bottom: 1rem;
}

.quiz-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 0.75rem;
}

.quiz-option {
    padding: 0.75rem 1rem;
    background: var(--color-bg-light);
    border: 2px solid transparent;
    border-radius: var(--radius-medium);
    cursor: pointer;
    transition: var(--transition-fast);
    font-size: 0.95rem;
    text-align: left;
}

.quiz-option:hover {
    border-color: var(--color-primary);
    background: rgba(52, 152, 219, 0.1);
}

.quiz-option.selected {
    border-color: var(--color-primary);
    background: rgba(52, 152, 219, 0.2);
}

.quiz-option.correct {
    border-color: var(--color-success);
    background: rgba(39, 174, 96, 0.2);
}

.quiz-option.incorrect {
    border-color: var(--color-accent);
    background: rgba(231, 76, 60, 0.2);
}

.quiz-feedback {
    margin-top: 1rem;
    padding: 0.75rem;
    border-radius: var(--radius-small);
    font-size: 0.9rem;
    display: none;
}

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

.quiz-feedback.correct {
    background: rgba(39, 174, 96, 0.1);
    color: var(--color-success);
}

.quiz-feedback.incorrect {
    background: rgba(231, 76, 60, 0.1);
    color: var(--color-accent);
}

.quiz-result {
    text-align: center;
    padding: 1.5rem;
    background: var(--color-bg-light);
    border-radius: var(--radius-medium);
    margin-top: 1rem;
    display: none;
}

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

/* CTA Final */
.cta-final {
    text-align: center;
    padding: 3rem 2rem;
    background: var(--color-bg-light);
    border-radius: var(--radius-large);
    margin-top: 3rem;
}

.cta-final h3 {
    color: var(--color-primary);
    margin-bottom: 1rem;
}

/* Footer */
.footer {
    background: var(--color-bg-dark);
    color: var(--color-text-muted);
    padding: 3rem 0;
    text-align: center;
}

.footer p {
    margin: 0.5rem 0;
}

.footer-note {
    font-size: 0.9rem;
}

.footer-references {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.references-title {
    font-weight: 600;
    color: var(--color-text-muted-light);
    margin-bottom: 0.75rem;
    font-size: 0.95rem;
}

.reference {
    font-size: 0.85rem;
    color: var(--color-text-muted-light);
    margin: 0.3rem 0;
    line-height: 1.5;
}

.reference em {
    font-style: italic;
}

/* Responsive Design */
@media (max-width: 768px) {
    body {
        font-size: 16px;
    }

    .container {
        padding: 0 1rem;
    }

    .nav-dots {
        right: 1rem;
    }

    .section {
        padding: 4rem 0;
    }

    .section-number {
        font-size: 3rem;
        top: 1rem;
        left: 1rem;
    }

    .concept-cards {
        grid-template-columns: 1fr;
    }

    .tooltip {
        width: 250px;
        left: auto;
        right: -50%;
        transform: translateY(10px);
    }

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

    .strategy-step {
        flex-direction: column;
        align-items: flex-start;
    }

    .feedback-loop {
        grid-template-columns: 1fr;
        grid-template-rows: repeat(5, auto);
    }

    .loop-center {
        grid-column: 1;
        grid-row: 3;
    }

    .loop-item-1 { grid-column: 1; grid-row: 1; }
    .loop-item-2 { grid-column: 1; grid-row: 2; }
    .loop-item-3 { grid-column: 1; grid-row: 4; }
    .loop-item-4 { grid-column: 1; grid-row: 5; }

    .loop-arrow {
        display: none;
    }

    .comparison-table th,
    .comparison-table td {
        padding: 0.75rem;
        font-size: 0.9rem;
    }

    .quiz-options {
        grid-template-columns: 1fr;
    }
}

/* Print Styles */
@media print {
    .progress-container,
    .nav-dots,
    .cta-button,
    .loop-controls,
    .quiz-section {
        display: none;
    }

    .section {
        min-height: auto;
        page-break-inside: avoid;
    }

    .video-container {
        display: none;
    }
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section.visible .concept-card,
.section.visible .vuca-item,
.section.visible .strategy-step,
.section.visible .insight-card {
    animation: fadeInUp 0.6s ease forwards;
}

.section.visible .concept-card:nth-child(1) { animation-delay: 0.1s; }
.section.visible .concept-card:nth-child(2) { animation-delay: 0.2s; }
.section.visible .concept-card:nth-child(3) { animation-delay: 0.3s; }

.section.visible .vuca-item:nth-child(1) { animation-delay: 0.1s; }
.section.visible .vuca-item:nth-child(2) { animation-delay: 0.2s; }
.section.visible .vuca-item:nth-child(3) { animation-delay: 0.3s; }
.section.visible .vuca-item:nth-child(4) { animation-delay: 0.4s; }

.section.visible .strategy-step:nth-child(2) { animation-delay: 0.1s; }
.section.visible .strategy-step:nth-child(3) { animation-delay: 0.2s; }
.section.visible .strategy-step:nth-child(4) { animation-delay: 0.3s; }

/* ========================================
   New Components for Issue #4
   ======================================== */

/* YouTube Embed Responsive */
.video-container iframe {
    width: 100%;
    aspect-ratio: 16 / 9;
    border-radius: var(--radius-medium);
}

/* Concept Cards on Dark Background */
.concept-card-dark {
    background: rgba(255, 255, 255, 0.1);
    color: var(--color-text-light);
}

.concept-card-dark h3 {
    color: var(--color-secondary);
}

.concept-card-dark p {
    color: var(--color-text-muted-light);
}

/* Requirements Grid */
.requirements-container {
    margin: 3rem 0;
}

.requirements-container h3 {
    text-align: center;
    margin-bottom: 2rem;
}

.requirements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

/* Flip Card Container */
.requirement-item {
    perspective: 1000px;
    height: 180px;
    cursor: pointer;
}

.requirement-item .card-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

.requirement-item:hover .card-inner {
    transform: rotateY(180deg);
}

/* Front and Back faces */
.requirement-item .card-front,
.requirement-item .card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    border-radius: var(--radius-large);
    padding: 1.5rem;
    display: flex;
    gap: 1rem;
}

.requirement-item .card-front {
    background: rgba(255, 255, 255, 0.1);
}

.requirement-item .card-back {
    background: var(--color-bg-dark);
    transform: rotateY(180deg);
    flex-direction: column;
    justify-content: center;
    color: var(--color-text-light);
    font-size: 0.95rem;
    line-height: 1.6;
}

.requirement-item .card-back em {
    display: block;
    margin-top: 0.75rem;
    opacity: 0.8;
}

.req-icon {
    font-size: 2rem;
    flex-shrink: 0;
}

.req-content h4 {
    color: var(--color-secondary);
    margin-bottom: 0.25rem;
}

.req-content p {
    color: var(--color-text-muted-light);
    font-size: 0.9rem;
    margin: 0;
}

/* Connection List */
.connection-list {
    list-style: none;
    padding: 0;
    margin: 1rem 0 0;
}

.connection-list li {
    padding: 0.5rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.connection-list li:last-child {
    border-bottom: none;
}

/* Scenario Exercise */
.scenario-exercise {
    margin-top: 3rem;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-large);
}

.scenario-exercise h3 {
    text-align: center;
    margin-bottom: 0.5rem;
}

.exercise-intro {
    text-align: center;
    color: var(--color-text-muted-light);
    margin-bottom: 2rem;
}

.scenario-statements {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.scenario-statement {
    background: rgba(255, 255, 255, 0.1);
    padding: 1.5rem;
    border-radius: var(--radius-medium);
    transition: var(--transition-fast);
}

.statement-text {
    font-style: italic;
    margin-bottom: 1rem;
    color: var(--color-text-light);
}

.statement-buttons {
    display: flex;
    gap: 1rem;
}

.statement-btn {
    flex: 1;
    padding: 0.75rem 1.5rem;
    border: 2px solid rgba(255, 255, 255, 0.3);
    background: transparent;
    color: var(--color-text-light);
    border-radius: var(--radius-medium);
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: var(--transition-fast);
}

.statement-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--color-primary);
}

.statement-btn.correct {
    background: rgba(39, 174, 96, 0.3);
    border-color: var(--color-success);
}

.statement-btn.incorrect {
    background: rgba(231, 76, 60, 0.3);
    border-color: var(--color-accent);
}

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

.statement-feedback {
    margin-top: 1rem;
    padding: 0.75rem;
    border-radius: var(--radius-small);
    font-size: 0.9rem;
    display: none;
}

.statement-feedback.show {
    display: block;
}

.statement-feedback.correct {
    background: rgba(39, 174, 96, 0.1);
    color: var(--color-success);
}

.statement-feedback.incorrect {
    background: rgba(231, 76, 60, 0.1);
    color: #f5a89a;
}

.scenario-result {
    margin-top: 2rem;
    padding: 1.5rem;
    background: rgba(52, 152, 219, 0.2);
    border-radius: var(--radius-medium);
    text-align: center;
    display: none;
}

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

/* Organization Comparison */
.org-comparison {
    margin: 3rem 0;
}

.org-comparison h3 {
    text-align: center;
    margin-bottom: 2rem;
}

.org-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.org-card {
    padding: 2rem;
    border-radius: var(--radius-large);
    text-align: center;
}

.org-card-tinman {
    background: linear-gradient(135deg, #7f8c8d 0%, #95a5a6 100%);
    color: white;
}

.org-card-octopus {
    background: linear-gradient(135deg, var(--color-primary) 0%, #2980b9 100%);
    color: white;
}

.org-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.org-card h4 {
    margin-bottom: 0.25rem;
}

.org-subtitle {
    font-size: 0.9rem;
    opacity: 0.8;
    margin-bottom: 1.5rem;
}

.org-traits {
    list-style: none;
    padding: 0;
    text-align: left;
    margin-bottom: 1.5rem;
}

.org-traits li {
    padding: 0.5rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    font-size: 0.95rem;
}

.org-traits li:last-child {
    border-bottom: none;
}

.org-traits li::before {
    content: "→ ";
    opacity: 0.7;
}

.org-result {
    font-weight: 600;
    padding: 0.75rem;
    background: rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-small);
    font-size: 0.9rem;
}

/* Antipattern Cards */
.antipatterns-container {
    margin: 3rem 0;
}

.antipatterns-container h3 {
    text-align: center;
    margin-bottom: 2rem;
}

.antipattern-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.antipattern-card {
    background: rgba(231, 76, 60, 0.1);
    border: 2px solid rgba(231, 76, 60, 0.2);
    padding: 1.5rem;
    border-radius: var(--radius-large);
    text-align: center;
    transition: var(--transition-medium);
}

.antipattern-card:hover {
    transform: translateY(-3px);
    border-color: rgba(231, 76, 60, 0.4);
}

.antipattern-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.antipattern-card h4 {
    color: #f5a89a;
    margin-bottom: 0.5rem;
}

.antipattern-card p {
    color: var(--color-text-muted);
    font-size: 0.9rem;
    margin: 0;
}

/* Octopus Principles */
.octopus-principles {
    margin: 3rem 0;
}

.octopus-principles h3 {
    text-align: center;
    margin-bottom: 2rem;
}

.principle-cards {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.principle-card {
    display: flex;
    gap: 1.5rem;
    padding: 2rem;
    background: white;
    border-radius: var(--radius-large);
    box-shadow: var(--shadow-soft);
    transition: var(--transition-medium);
}

.principle-card:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow-medium);
}

.principle-number {
    flex-shrink: 0;
    width: 50px;
    height: 50px;
    background: var(--color-success);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
}

.principle-content h4 {
    color: var(--color-success);
    margin-bottom: 0.5rem;
}

.principle-content p {
    color: var(--color-text-muted);
    margin: 0;
}

/* Animation delays for new components */
.section.visible .requirement-item:nth-child(1) { animation-delay: 0.1s; }
.section.visible .requirement-item:nth-child(2) { animation-delay: 0.15s; }
.section.visible .requirement-item:nth-child(3) { animation-delay: 0.2s; }
.section.visible .requirement-item:nth-child(4) { animation-delay: 0.25s; }
.section.visible .requirement-item:nth-child(5) { animation-delay: 0.3s; }

.section.visible .org-card:nth-child(1) { animation-delay: 0.1s; }
.section.visible .org-card:nth-child(2) { animation-delay: 0.2s; }

.section.visible .antipattern-card:nth-child(1) { animation-delay: 0.1s; }
.section.visible .antipattern-card:nth-child(2) { animation-delay: 0.2s; }
.section.visible .antipattern-card:nth-child(3) { animation-delay: 0.3s; }

.section.visible .principle-card:nth-child(1) { animation-delay: 0.1s; }
.section.visible .principle-card:nth-child(2) { animation-delay: 0.2s; }
.section.visible .principle-card:nth-child(3) { animation-delay: 0.3s; }

.section.visible .requirement-item,
.section.visible .org-card,
.section.visible .antipattern-card,
.section.visible .principle-card {
    animation: fadeInUp 0.6s ease forwards;
}

/* Responsive adjustments for new components */
@media (max-width: 768px) {
    .requirements-grid {
        grid-template-columns: 1fr;
    }

    .requirement-item .tooltip {
        left: -1rem;
        right: -1rem;
        width: auto;
    }

    .org-cards {
        grid-template-columns: 1fr;
    }

    .principle-card {
        flex-direction: column;
        align-items: flex-start;
    }

    .statement-buttons {
        flex-direction: column;
    }
}