/**
 * Functional Safety Course - Advanced Slide System
 * Version: 5.0 - Based on LESSON_SPEC_GlobalArchitecture.md
 *
 * Supports:
 * - Title slides with animated maps
 * - Objectives with checkboxes
 * - Interactive timelines
 * - Tree diagrams
 * - Pyramid visualizations (SIL)
 * - Circular lifecycle diagrams
 * - Accordions
 * - Card flip grids
 * - Split-screen layouts
 * - Inline quizzes
 */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

/* ============================================
   CSS VARIABLES
   ============================================ */
:root {
    --fs-font: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
    --fs-mono: 'JetBrains Mono', monospace;

    /* Brand Colors */
    --fs-primary: #2563eb;
    --fs-primary-dark: #1d4ed8;
    --fs-secondary: #0f172a;
    --fs-accent: #06b6d4;

    /* Status Colors */
    --fs-success: #10b981;
    --fs-warning: #f59e0b;
    --fs-danger: #ef4444;
    --fs-info: #3b82f6;

    /* SIL Colors */
    --sil-4: #dc2626;
    --sil-3: #ea580c;
    --sil-2: #f59e0b;
    --sil-1: #84cc16;

    /* Neutrals */
    --fs-bg: #ffffff;
    --fs-bg-alt: #f8fafc;
    --fs-bg-dark: #0f172a;
    --fs-border: #e2e8f0;
    --fs-text: #1e293b;
    --fs-text-muted: #64748b;
    --fs-text-light: #94a3b8;

    /* Spacing */
    --fs-radius: 1rem;
    --fs-radius-sm: 0.5rem;
    --fs-radius-lg: 1.5rem;

    /* Shadows */
    --fs-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    --fs-shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
    --fs-shadow-xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

/* ============================================
   HIDE WP/LP DEFAULTS (Keep sidebar visible)
   ============================================ */
#comments,
.comments-area {
    display: none !important;
}

/* Main content area - use available space */
body.single-lp_lesson .learn-press-content-item-summary {
    max-width: 100% !important;
    width: 100% !important;
    padding: 0 !important;
}

/* ============================================
   MAIN CONTAINER
   ============================================ */
.fs-interactive-lesson {
    font-family: var(--fs-font);
    background: linear-gradient(180deg, #f8fafc 0%, #e2e8f0 100%);
    min-height: 100vh;
    padding: 1.5rem;
}

/* ============================================
   NAVIGATION BAR
   ============================================ */
.fs-slide-nav-bar {
    position: sticky;
    top: 1rem;
    z-index: 100;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: var(--fs-radius);
    padding: 0.875rem 1.25rem;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    box-shadow: var(--fs-shadow);
    border: 1px solid var(--fs-border);
    max-width: 100%;
    margin-left: auto;
    margin-right: auto;
}

.fs-slide-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    border-radius: var(--fs-radius-sm);
    font-family: var(--fs-font);
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s ease;
    border: 2px solid var(--fs-border);
    background: white;
    color: var(--fs-text);
}

.fs-slide-btn:hover:not(:disabled) {
    background: var(--fs-bg-alt);
    border-color: var(--fs-text-muted);
    transform: translateY(-1px);
}

.fs-slide-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.fs-slide-btn.primary {
    background: linear-gradient(135deg, var(--fs-primary), var(--fs-primary-dark));
    border-color: var(--fs-primary);
    color: white;
}

.fs-slide-btn.primary:hover:not(:disabled) {
    box-shadow: 0 4px 14px rgba(37, 99, 235, 0.4);
    transform: translateY(-2px);
}

.fs-slide-btn svg {
    width: 1.125rem;
    height: 1.125rem;
}

.fs-slide-progress {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.375rem;
    flex: 1;
    max-width: 350px;
}

.fs-progress-container {
    width: 100%;
    height: 6px;
    background: var(--fs-border);
    border-radius: 3px;
    overflow: hidden;
}

.fs-progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--fs-primary), var(--fs-accent));
    border-radius: 3px;
    transition: width 0.4s ease;
}

.fs-slide-counter {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--fs-text-muted);
}

/* ============================================
   SLIDE BASE
   ============================================ */
.fs-slide {
    display: none;
    animation: slideIn 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    max-width: 100%;
    width: 100%;
    margin: 0 auto;
}

.fs-slide.active {
    display: block;
}

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

.fs-slide-card {
    background: var(--fs-bg);
    border-radius: var(--fs-radius-lg);
    box-shadow: var(--fs-shadow-lg);
    overflow: hidden;
    border: 1px solid var(--fs-border);
}

/* Slide Header */
.fs-slide-header {
    background: linear-gradient(135deg, var(--fs-secondary) 0%, #334155 100%);
    color: white;
    padding: 2rem 2.5rem;
    position: relative;
    overflow: hidden;
}

.fs-slide-header::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 300px;
    height: 100%;
    background: linear-gradient(135deg, transparent, rgba(6, 182, 212, 0.15));
    pointer-events: none;
}

.fs-slide-number {
    display: inline-block;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(4px);
    padding: 0.375rem 1rem;
    border-radius: 2rem;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    margin-bottom: 0.75rem;
}

.fs-slide-header h2 {
    font-size: 2rem;
    font-weight: 700;
    margin: 0;
    line-height: 1.3;
    position: relative;
    color: white !important;
}

.fs-slide-header,
.fs-slide-header *,
.fs-slide-header span,
.fs-slide-number {
    color: white !important;
}

/* Slide Content */
.fs-slide-content {
    padding: 3rem;
    font-size: 1.25rem;
    line-height: 1.8;
    color: var(--fs-text);
}

.fs-slide-content h2,
.fs-slide-content h3 {
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
}

.fs-slide-content p {
    font-size: 1.25rem;
    margin-bottom: 1.25rem;
}

.fs-slide-content li {
    font-size: 1.2rem;
    margin-bottom: 0.75rem;
}

/* ============================================
   TITLE SLIDE (Type: title)
   ============================================ */
.fs-title-slide .fs-slide-card {
    background: linear-gradient(135deg, var(--fs-secondary) 0%, #1e3a5f 100%);
    min-height: 60vh;
    display: flex;
    flex-direction: column;
}

.fs-title-slide .fs-slide-header {
    background: transparent;
    text-align: center;
    padding: 3rem 2.5rem;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.fs-title-slide .fs-slide-number {
    background: rgba(6, 182, 212, 0.2);
    border: 1px solid rgba(6, 182, 212, 0.3);
    color: #67e8f9;
}

.fs-title-slide h2 {
    font-size: 2.75rem;
    font-weight: 800;
    background: linear-gradient(135deg, white, #cbd5e1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.fs-title-subtitle {
    font-size: 1.25rem;
    color: rgba(255, 255, 255, 0.7);
    margin-top: 1rem;
}

/* Statistics Counter */
.fs-stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1.5rem;
    padding: 2rem;
    background: rgba(0, 0, 0, 0.2);
    margin-top: auto;
}

.fs-stat-item {
    text-align: center;
    color: white;
}

.fs-stat-value {
    font-size: 2.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, #67e8f9, white);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.fs-stat-label {
    font-size: 0.8125rem;
    color: rgba(255, 255, 255, 0.7);
    margin-top: 0.25rem;
}

/* Start Button */
.fs-start-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    background: white;
    color: var(--fs-secondary);
    padding: 1rem 2rem;
    border-radius: var(--fs-radius-sm);
    font-size: 1rem;
    font-weight: 700;
    margin-top: 2rem;
    cursor: pointer;
    border: none;
    transition: all 0.3s ease;
}

.fs-start-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.3);
}

/* ============================================
   OBJECTIVES SLIDE
   ============================================ */
.fs-objectives-slide .fs-slide-card {
    border-left: 4px solid var(--fs-success);
}

.objectives-intro {
    font-size: 1.125rem;
    color: var(--fs-text-muted);
    margin-bottom: 1.5rem;
}

.objectives-grid {
    display: grid;
    gap: 1rem;
}

.objective-card {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.25rem;
    background: var(--fs-bg-alt);
    border-radius: var(--fs-radius-sm);
    border: 1px solid var(--fs-border);
    cursor: pointer;
    transition: all 0.2s ease;
}

.objective-card:hover {
    background: white;
    border-color: var(--fs-success);
    transform: translateX(5px);
}

.objective-icon {
    flex-shrink: 0;
    width: 2.5rem;
    height: 2.5rem;
    background: linear-gradient(135deg, var(--fs-success), #059669);
    border-radius: var(--fs-radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1rem;
}

.objective-content h4 {
    margin: 0 0 0.25rem 0;
    font-size: 1rem;
    font-weight: 600;
    color: var(--fs-text);
}

.objective-content p {
    margin: 0;
    font-size: 0.875rem;
    color: var(--fs-text-muted);
}

/* Checkbox style */
.objective-card input[type="checkbox"] {
    display: none;
}

.objective-card .checkmark {
    flex-shrink: 0;
    width: 1.5rem;
    height: 1.5rem;
    border: 2px solid var(--fs-text-muted);
    border-radius: 0.375rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    margin-left: auto;
}

.objective-card input:checked + .checkmark {
    background: var(--fs-success);
    border-color: var(--fs-success);
}

.objective-card input:checked + .checkmark::after {
    content: '';
    width: 0.4rem;
    height: 0.7rem;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
    margin-bottom: 2px;
}

/* ============================================
   INTERACTIVE TIMELINE
   ============================================ */
.fs-timeline {
    position: relative;
    padding: 2rem 0;
}

.fs-timeline::before {
    content: '';
    position: absolute;
    left: 2rem;
    top: 0;
    bottom: 0;
    width: 4px;
    background: linear-gradient(180deg, var(--fs-primary), var(--fs-accent));
    border-radius: 2px;
}

.timeline-event {
    position: relative;
    padding-left: 5rem;
    margin-bottom: 2rem;
    cursor: pointer;
}

.timeline-year {
    position: absolute;
    left: 0;
    width: 4rem;
    height: 4rem;
    background: white;
    border: 4px solid var(--fs-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    font-size: 0.875rem;
    color: var(--fs-primary);
    z-index: 1;
    transition: all 0.3s ease;
}

.timeline-event:hover .timeline-year {
    background: var(--fs-primary);
    color: white;
    transform: scale(1.1);
}

.timeline-event.highlight .timeline-year {
    background: var(--fs-primary);
    color: white;
    box-shadow: 0 0 0 8px rgba(37, 99, 235, 0.2);
}

.timeline-card {
    background: white;
    border: 1px solid var(--fs-border);
    border-radius: var(--fs-radius-sm);
    padding: 1.25rem;
    transition: all 0.2s ease;
}

.timeline-event:hover .timeline-card {
    box-shadow: var(--fs-shadow-lg);
    border-color: var(--fs-primary);
}

.timeline-card h4 {
    margin: 0 0 0.5rem 0;
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--fs-text);
}

.timeline-card p {
    margin: 0;
    font-size: 0.9375rem;
    color: var(--fs-text-muted);
}

.timeline-details {
    display: none;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--fs-border);
    font-size: 0.875rem;
}

.timeline-event.expanded .timeline-details {
    display: block;
    animation: expandIn 0.3s ease;
}

@keyframes expandIn {
    from { opacity: 0; max-height: 0; }
    to { opacity: 1; max-height: 500px; }
}

/* ============================================
   SIL PYRAMID
   ============================================ */
.fs-sil-pyramid {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    max-width: 600px;
    margin: 2rem auto;
}

.pyramid-tier {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1.5rem;
    color: white;
    font-weight: 700;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    border-radius: var(--fs-radius-sm);
    position: relative;
}

.pyramid-tier:hover {
    transform: scale(1.02);
    z-index: 10;
}

.pyramid-tier.sil-4 {
    width: 40%;
    background: linear-gradient(135deg, var(--sil-4), #b91c1c);
}

.pyramid-tier.sil-3 {
    width: 55%;
    background: linear-gradient(135deg, var(--sil-3), #c2410c);
}

.pyramid-tier.sil-2 {
    width: 70%;
    background: linear-gradient(135deg, var(--sil-2), #d97706);
}

.pyramid-tier.sil-1 {
    width: 85%;
    background: linear-gradient(135deg, var(--sil-1), #65a30d);
}

.pyramid-tier-content {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.pyramid-tier-label {
    font-size: 1.5rem;
    font-weight: 800;
}

.pyramid-tier-pfd {
    font-size: 0.75rem;
    opacity: 0.9;
    margin-top: 0.25rem;
}

.pyramid-details {
    display: none;
    position: absolute;
    left: 105%;
    top: 50%;
    transform: translateY(-50%);
    background: white;
    color: var(--fs-text);
    padding: 1rem;
    border-radius: var(--fs-radius-sm);
    box-shadow: var(--fs-shadow-lg);
    width: 250px;
    z-index: 100;
    border: 1px solid var(--fs-border);
}

.pyramid-tier:hover .pyramid-details {
    display: block;
    animation: fadeIn 0.2s ease;
}

/* ============================================
   CIRCULAR LIFECYCLE DIAGRAM
   ============================================ */
.fs-lifecycle-circle {
    position: relative;
    width: 400px;
    height: 400px;
    margin: 2rem auto;
}

.lifecycle-center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 120px;
    height: 120px;
    background: var(--fs-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 700;
    font-size: 0.875rem;
    text-align: center;
    z-index: 10;
}

.lifecycle-phase {
    position: absolute;
    width: 80px;
    height: 80px;
    background: white;
    border: 3px solid;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.6875rem;
    font-weight: 600;
    text-align: center;
    padding: 0.5rem;
}

.lifecycle-phase:hover {
    transform: scale(1.15);
    z-index: 20;
    box-shadow: var(--fs-shadow-lg);
}

.lifecycle-phase.analysis { border-color: #3b82f6; color: #3b82f6; }
.lifecycle-phase.spec { border-color: #10b981; color: #10b981; }
.lifecycle-phase.realization { border-color: #f59e0b; color: #f59e0b; }
.lifecycle-phase.validation { border-color: #8b5cf6; color: #8b5cf6; }
.lifecycle-phase.operation { border-color: #ec4899; color: #ec4899; }

/* Position phases around circle */
.lifecycle-phase:nth-child(1) { top: 0; left: 50%; transform: translateX(-50%); }
.lifecycle-phase:nth-child(2) { top: 10%; right: 10%; }
.lifecycle-phase:nth-child(3) { top: 40%; right: 0; transform: translateY(-50%); }
.lifecycle-phase:nth-child(4) { bottom: 10%; right: 10%; }
.lifecycle-phase:nth-child(5) { bottom: 0; left: 50%; transform: translateX(-50%); }
.lifecycle-phase:nth-child(6) { bottom: 10%; left: 10%; }
.lifecycle-phase:nth-child(7) { top: 40%; left: 0; transform: translateY(-50%); }
.lifecycle-phase:nth-child(8) { top: 10%; left: 10%; }

/* ============================================
   ACCORDION
   ============================================ */
.fs-accordion {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.accordion-item {
    border: 1px solid var(--fs-border);
    border-radius: var(--fs-radius-sm);
    overflow: hidden;
    background: white;
}

.accordion-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.25rem;
    cursor: pointer;
    transition: background 0.2s ease;
}

.accordion-header:hover {
    background: var(--fs-bg-alt);
}

.accordion-icon {
    flex-shrink: 0;
    width: 2.5rem;
    height: 2.5rem;
    background: var(--fs-primary);
    border-radius: var(--fs-radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.875rem;
    font-weight: 700;
}

.accordion-title {
    flex: 1;
}

.accordion-title h4 {
    margin: 0;
    font-size: 1rem;
    font-weight: 600;
    color: var(--fs-text);
}

.accordion-title p {
    margin: 0.25rem 0 0 0;
    font-size: 0.8125rem;
    color: var(--fs-text-muted);
}

.accordion-toggle {
    width: 2rem;
    height: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--fs-text-muted);
    transition: transform 0.3s ease;
}

.accordion-item.open .accordion-toggle {
    transform: rotate(180deg);
}

.accordion-content {
    display: none;
    padding: 0 1.25rem 1.25rem 1.25rem;
    border-top: 1px solid var(--fs-border);
}

.accordion-item.open .accordion-content {
    display: block;
    animation: expandIn 0.3s ease;
}

/* ============================================
   CARD FLIP GRID
   ============================================ */
.fs-flip-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.flip-card {
    perspective: 1000px;
    height: 350px;
}

.flip-card-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    transform-style: preserve-3d;
    cursor: pointer;
}

.flip-card:hover .flip-card-inner,
.flip-card.flipped .flip-card-inner {
    transform: rotateY(180deg);
}

.flip-card-front,
.flip-card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: var(--fs-radius);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    border: 1px solid var(--fs-border);
}

.flip-card-front {
    background: linear-gradient(135deg, var(--fs-secondary), #334155);
    color: white;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.flip-card-front h3 {
    font-size: 2rem;
    font-weight: 800;
    margin: 0 0 0.5rem 0;
}

.flip-card-front p {
    font-size: 0.875rem;
    opacity: 0.8;
    margin: 0;
}

.flip-card-back {
    background: white;
    transform: rotateY(180deg);
    overflow-y: auto;
}

.flip-card-back h4 {
    margin: 0 0 1rem 0;
    font-size: 1rem;
    font-weight: 700;
    color: var(--fs-text);
}

/* ============================================
   SPLIT SCREEN
   ============================================ */
.fs-split-screen {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.split-panel {
    background: white;
    border: 1px solid var(--fs-border);
    border-radius: var(--fs-radius);
    overflow: hidden;
}

.split-panel-header {
    background: var(--fs-bg-alt);
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--fs-border);
}

.split-panel-header h3 {
    margin: 0;
    font-size: 1rem;
    font-weight: 700;
}

.split-panel-content {
    padding: 1.25rem;
    max-height: 400px;
    overflow-y: auto;
}

/* ============================================
   INLINE QUIZ
   ============================================ */
.fs-quiz {
    background: white;
    border: 1px solid var(--fs-border);
    border-radius: var(--fs-radius);
    overflow: hidden;
}

.quiz-header {
    background: linear-gradient(135deg, var(--fs-primary), var(--fs-primary-dark));
    color: white;
    padding: 1.25rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.quiz-progress {
    display: flex;
    gap: 0.5rem;
}

.quiz-progress-dot {
    width: 0.75rem;
    height: 0.75rem;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
}

.quiz-progress-dot.current {
    background: white;
}

.quiz-progress-dot.correct {
    background: var(--fs-success);
}

.quiz-progress-dot.incorrect {
    background: var(--fs-danger);
}

.quiz-question {
    padding: 1.5rem;
}

.quiz-question h4 {
    margin: 0 0 1.5rem 0;
    font-size: 1.125rem;
    font-weight: 600;
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.quiz-option {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--fs-bg-alt);
    border: 2px solid var(--fs-border);
    border-radius: var(--fs-radius-sm);
    cursor: pointer;
    transition: all 0.2s ease;
}

.quiz-option:hover:not(.selected):not(.disabled) {
    border-color: var(--fs-primary);
    background: white;
}

.quiz-option.selected {
    border-color: var(--fs-primary);
    background: rgba(37, 99, 235, 0.05);
}

.quiz-option.correct {
    border-color: var(--fs-success);
    background: rgba(16, 185, 129, 0.1);
}

.quiz-option.incorrect {
    border-color: var(--fs-danger);
    background: rgba(239, 68, 68, 0.1);
}

.quiz-option-marker {
    width: 1.5rem;
    height: 1.5rem;
    border: 2px solid var(--fs-text-muted);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.75rem;
}

.quiz-option.selected .quiz-option-marker {
    background: var(--fs-primary);
    border-color: var(--fs-primary);
    color: white;
}

.quiz-feedback {
    margin-top: 1.5rem;
    padding: 1rem;
    border-radius: var(--fs-radius-sm);
    display: none;
}

.quiz-feedback.correct {
    display: block;
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid var(--fs-success);
    color: var(--fs-success);
}

.quiz-feedback.incorrect {
    display: block;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--fs-danger);
    color: var(--fs-danger);
}

/* ============================================
   CALLOUT BOXES
   ============================================ */
.callout-box {
    padding: 1.25rem;
    border-radius: var(--fs-radius-sm);
    margin: 1.25rem 0;
    display: flex;
    gap: 1rem;
}

.callout-icon {
    flex-shrink: 0;
    width: 2rem;
    height: 2rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
}

.callout-box.info {
    background: #eff6ff;
    border-left: 4px solid var(--fs-primary);
}

.callout-box.info .callout-icon {
    background: var(--fs-primary);
    color: white;
}

.callout-box.success {
    background: #ecfdf5;
    border-left: 4px solid var(--fs-success);
}

.callout-box.success .callout-icon {
    background: var(--fs-success);
    color: white;
}

.callout-box.warning {
    background: #fffbeb;
    border-left: 4px solid var(--fs-warning);
}

.callout-box.warning .callout-icon {
    background: var(--fs-warning);
    color: white;
}

.callout-box.danger {
    background: #fef2f2;
    border-left: 4px solid var(--fs-danger);
}

.callout-box.danger .callout-icon {
    background: var(--fs-danger);
    color: white;
}

/* ============================================
   DOT NAVIGATION
   ============================================ */
.fs-slide-dots {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 1.5rem;
}

.fs-slide-dot {
    width: 0.625rem;
    height: 0.625rem;
    border-radius: 50%;
    background: var(--fs-border);
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
    padding: 0;
}

.fs-slide-dot:hover {
    background: var(--fs-text-muted);
}

.fs-slide-dot.active {
    background: var(--fs-primary);
    transform: scale(1.3);
}

/* ============================================
   KEYBOARD HINT
   ============================================ */
.fs-keyboard-hint {
    text-align: center;
    margin-top: 1rem;
    font-size: 0.75rem;
    color: var(--fs-text-muted);
}

.fs-keyboard-hint kbd {
    display: inline-block;
    background: white;
    border: 1px solid var(--fs-border);
    border-radius: 0.25rem;
    padding: 0.125rem 0.375rem;
    font-family: var(--fs-mono);
    font-size: 0.6875rem;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
}

/* ============================================
   COMPLETION
   ============================================ */
.fs-completion-box {
    text-align: center;
    padding: 2rem;
}

.fs-completion-celebration {
    background: linear-gradient(135deg, var(--fs-success), #059669);
    color: white;
    border-radius: var(--fs-radius);
    padding: 2.5rem;
    max-width: 450px;
    margin: 0 auto;
    animation: celebrateIn 0.5s ease;
}

@keyframes celebrateIn {
    from { opacity: 0; transform: scale(0.9); }
    to { opacity: 1; transform: scale(1); }
}

.celebration-icon {
    font-size: 3.5rem;
    display: block;
    margin-bottom: 1rem;
}

.fs-completion-celebration h4 {
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 0 0.5rem 0;
}

.fs-completion-celebration p {
    font-size: 1rem;
    opacity: 0.9;
    margin: 0 0 1.5rem 0;
}

.fs-btn-next-lesson {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: white;
    color: var(--fs-success);
    padding: 0.875rem 1.5rem;
    border-radius: var(--fs-radius-sm);
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s ease;
}

.fs-btn-next-lesson:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
    .fs-interactive-lesson {
        padding: 1rem;
    }

    .fs-slide-nav-bar {
        flex-wrap: wrap;
        gap: 0.75rem;
    }

    .fs-slide-btn span {
        display: none;
    }

    .fs-slide-progress {
        order: -1;
        width: 100%;
        max-width: 100%;
    }

    .fs-slide-header {
        padding: 1.5rem;
    }

    .fs-slide-header h2 {
        font-size: 1.375rem;
    }

    .fs-slide-content {
        padding: 1.5rem;
    }

    .fs-title-slide h2 {
        font-size: 1.75rem;
    }

    .fs-split-screen {
        grid-template-columns: 1fr;
    }

    .fs-timeline::before {
        left: 1.25rem;
    }

    .timeline-event {
        padding-left: 3.5rem;
    }

    .timeline-year {
        width: 2.5rem;
        height: 2.5rem;
        font-size: 0.6875rem;
    }

    .fs-sil-pyramid .pyramid-tier {
        width: 100% !important;
    }

    .fs-keyboard-hint {
        display: none;
    }
}

/* ============================================
   PRINT
   ============================================ */
@media print {
    .fs-slide-nav-bar,
    .fs-slide-dots,
    .fs-keyboard-hint {
        display: none !important;
    }

    .fs-slide {
        display: block !important;
        page-break-after: always;
    }

    .fs-interactive-lesson {
        background: white !important;
    }
}