/* =========================================
   HRV Virtual Lab — Clinical Design Stylesheet
   ========================================= */

/* --- CSS Variables / Theme --- */
:root {
    /* Light clinical theme */
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-sidebar: #f1f5f9;
    --bg-card: #ffffff;
    --bg-card-hover: #f8fafc;
    
    /* Accent colors - heart/cardiac red theme */
    --accent: #e74c3c;
    --accent-light: #fbe9e7;
    --accent-dark: #c0392b;
    --accent-border: #f5b7b1;
    
    /* Secondary accent - calming blue for PNS */
    --accent-secondary: #27ae60;
    --accent-secondary-light: #e8f6ef;
    
    /* SNS Color */
    --sns-color: #e74c3c;
    --sns-light: #fbe9e7;
    
    /* PNS Color */
    --pns-color: #27ae60;
    --pns-light: #e8f6ef;
    
    /* Status colors */
    --success: #10b981;
    --success-light: #d1fae5;
    --warning: #f59e0b;
    --warning-light: #fef3c7;
    --danger: #ef4444;
    --danger-light: #fee2e2;
    
    /* Text colors */
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    
    /* Border colors */
    --border: #e2e8f0;
    --border-light: #f1f5f9;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1), 0 1px 2px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    
    /* Radius */
    --radius: 8px;
    --radius-sm: 6px;
    --radius-lg: 12px;
    
    /* Transitions */
    --transition: all 0.2s ease;
    --transition-slow: all 0.3s ease;
    
    /* Typography */
    --font-sans: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
    --font-mono: 'Fira Code', 'Consolas', monospace;
}

/* --- Reset & Base --- */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
    font-size: 15px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.hidden {
    display: none !important;
}

/* --- Loading Screen --- */
#loading-screen {
    position: fixed;
    inset: 0;
    background: linear-gradient(135deg, #fff5f5 0%, #ffffff 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity 0.5s ease;
}

#loading-screen.fade-out {
    opacity: 0;
    pointer-events: none;
}

.loader-content {
    text-align: center;
}

.loader-spinner {
    width: 80px;
    height: 80px;
    margin: 0 auto 24px;
}

.spinner-svg {
    animation: rotate 2s linear infinite;
}

.spinner-circle {
    animation: dash 1.5s ease-in-out infinite;
}

@keyframes rotate {
    100% { transform: rotate(360deg); }
}

@keyframes dash {
    0% { stroke-dasharray: 1, 150; stroke-dashoffset: 0; }
    50% { stroke-dasharray: 90, 150; stroke-dashoffset: -35; }
    100% { stroke-dasharray: 90, 150; stroke-dashoffset: -124; }
}

.loader-content h1 {
    font-size: 1.5rem;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.loader-content p {
    color: var(--text-muted);
    margin-bottom: 24px;
}

.load-bar {
    width: 200px;
    height: 4px;
    background: var(--border);
    border-radius: 2px;
    overflow: hidden;
    margin: 0 auto;
}

.load-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent) 0%, var(--accent-dark) 100%);
    width: 0%;
    transition: width 0.1s ease;
}

/* --- Main Layout --- */
#app {
    display: flex;
    min-height: 100vh;
}

/* --- Sidebar --- */
#sidebar-nav {
    background: var(--bg-card);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    width: 280px;
    z-index: 100;
}

.sidebar-header {
    padding: 24px 20px;
    border-bottom: 1px solid var(--border);
    text-align: center;
}

.sidebar-logo {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 12px;
}

.logo-image {
    max-width: 100%;
    max-height: 60px;
    object-fit: contain;
    border-radius: var(--radius);
}

.lab-title {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-bottom: 4px;
}

.lab-icon {
    font-size: 1.2rem;
    color: var(--accent);
}

.sidebar-header h2 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0;
}

.lab-subtitle {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Navigation Steps */
.nav-steps-vertical {
    flex: 1;
    padding: 8px;
    overflow-y: auto;
}

.nav-step {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: var(--radius);
    cursor: pointer;
    transition: var(--transition);
    margin-bottom: 4px;
}

.nav-step:hover {
    background: var(--bg-primary);
}

.nav-step.active {
    background: var(--accent-light);
}

.nav-step.completed .step-indicator {
    background: var(--success);
}

.step-indicator {
    width: 36px;
    height: 36px;
    background: var(--border);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.nav-step.active .step-indicator {
    background: var(--accent);
}

.step-indicator i {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.nav-step.active .step-indicator i,
.nav-step.completed .step-indicator i {
    color: white;
}

.step-check {
    display: none;
}

.nav-step.completed .step-check {
    display: flex;
    position: absolute;
    inset: 0;
    align-items: center;
    justify-content: center;
}

.step-content {
    flex: 1;
}

.step-label {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.nav-step.active .step-label {
    color: var(--accent-dark);
    font-weight: 600;
}

/* Locked step styling */
.nav-step.locked {
    opacity: 0.5;
    cursor: not-allowed;
}

.nav-step.locked:hover {
    background: transparent;
}

.nav-step.locked .step-indicator {
    background: var(--bg-secondary);
    color: var(--text-muted);
}

/* Sidebar Footer */
.sidebar-footer {
    padding: 16px;
    border-top: 1px solid var(--border);
}

.btn-glossary {
    width: 100%;
    padding: 12px;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

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

/* --- Main Content --- */
#main-content {
    flex: 1;
    margin-left: 280px;
    padding: 32px;
    min-height: 100vh;
}

.lab-step {
    display: none;
}

.lab-step.active {
    display: block;
}

.step-container {
    max-width: 1100px;
    margin: 0 auto;
}

/* Section Header */
.section-header {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 28px;
}

.section-header > i {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-dark) 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.25rem;
    flex-shrink: 0;
}

.section-header h2 {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.section-header p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* --- Welcome Card --- */
.welcome-card {
    text-align: center;
    padding: 40px 24px;
    margin-bottom: 32px;
}

.welcome-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--accent-light) 0%, #ffffff 100%);
    border: 1px solid var(--accent-border);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
}

.welcome-icon i {
    font-size: 2rem;
    color: var(--accent);
}

.welcome-card h2 {
    font-size: 1.85rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 10px;
    letter-spacing: -0.02em;
}

.welcome-subtitle {
    color: var(--text-secondary);
    font-size: 1.05rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

/* --- Info Grid --- */
.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
    margin-bottom: 32px;
}

.info-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.info-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--accent) 0%, var(--accent-dark) 100%);
    opacity: 0;
    transition: var(--transition);
}

.info-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-border);
}

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

.info-card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border);
}

.info-card-header i {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--accent-light) 0%, #ffffff 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    color: var(--accent);
    box-shadow: 0 2px 8px rgba(231, 76, 60, 0.15);
    transition: var(--transition);
}

.info-card:hover .info-card-header i {
    transform: scale(1.1);
    box-shadow: 0 4px 12px rgba(231, 76, 60, 0.25);
}

.info-card-header h3 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
}

.info-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.7;
}

.info-card ul {
    list-style: none;
    padding: 0;
}

.info-card ul li {
    padding: 8px 0;
    padding-left: 24px;
    position: relative;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.info-card ul li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 8px;
    height: 8px;
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-dark) 100%);
    border-radius: 50%;
    box-shadow: 0 0 0 3px var(--accent-light);
}

/* --- Science Section --- */
.science-section-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px;
    margin-bottom: 32px;
    box-shadow: var(--shadow);
    position: relative;
}

.science-section-card::after {
    content: '';
    position: absolute;
    top: 20px;
    right: 20px;
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--accent-light) 0%, transparent 100%);
    border-radius: 50%;
    opacity: 0.5;
    pointer-events: none;
}

.science-section-card > h3 {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 28px;
    padding-bottom: 18px;
    border-bottom: 2px solid var(--border);
}

.science-section-card > h3 i {
    color: var(--accent);
    font-size: 1.3rem;
}

.science-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}

.science-item {
    padding: 24px;
    background: linear-gradient(145deg, var(--bg-primary) 0%, #ffffff 100%);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.science-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(180deg, var(--accent) 0%, var(--accent-dark) 100%);
    opacity: 0;
    transition: var(--transition);
}

.science-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent-border);
}

.science-item:hover::before {
    opacity: 1;
}

.science-item h4 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 14px;
}

.science-item h4 i {
    color: var(--accent);
    font-size: 1rem;
    width: 32px;
    height: 32px;
    background: var(--accent-light);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.science-item:hover h4 i {
    background: var(--accent);
    color: white;
}

.science-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.7;
}

.science-item ul.signal-specs {
    list-style: none;
    padding: 0;
    margin: 0;
}

.science-item ul.signal-specs li {
    padding: 8px 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
    border-bottom: 1px dashed var(--border-light);
    display: flex;
    justify-content: space-between;
}

.science-item ul.signal-specs li:last-child {
    border-bottom: none;
}

.science-item ul.signal-specs li strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* --- Canvas/Visualization --- */
.muap-visualization {
    background: linear-gradient(180deg, var(--bg-card) 0%, var(--bg-primary) 100%);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px;
    margin-bottom: 32px;
    text-align: center;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}

.muap-visualization::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, var(--accent-light) 0%, transparent 60%);
    opacity: 0.3;
    pointer-events: none;
}

.muap-visualization canvas {
    max-width: 100%;
    height: auto;
    border-radius: var(--radius-lg);
    background: linear-gradient(180deg, #1a2332 0%, #0f1419 100%);
    border: 2px solid var(--border);
    box-shadow: var(--shadow-md), inset 0 0 60px rgba(0,0,0,0.3);
    position: relative;
    z-index: 1;
}

.canvas-caption {
    margin-top: 16px;
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 500;
    position: relative;
    z-index: 1;
}

/* --- Buttons --- */
.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    padding: 14px 28px;
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-dark) 100%);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 4px 14px rgba(231, 76, 60, 0.35);
    position: relative;
    overflow: hidden;
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: 0.5s;
}

.btn-primary:hover::before {
    left: 100%;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(231, 76, 60, 0.45);
}

.btn-primary.btn-lg {
    padding: 18px 42px;
    font-size: 1.05rem;
    border-radius: 50px;
}

.btn-secondary {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 10px 20px;
    border-radius: var(--radius);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
}

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

/* --- ANS Theory Section --- */
.ans-theory-container {
    display: flex;
    flex-direction: column;
    gap: 24px;
    margin-bottom: 32px;
}

.ans-intro-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
    text-align: center;
}

.ans-intro-card p {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

.ans-branches {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
}

.ans-card {
    background: var(--bg-card);
    border: 2px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: var(--transition);
}

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

.ans-card.sympathetic {
    border-color: var(--sns-light);
}

.ans-card.sympathetic:hover {
    border-color: var(--sns-color);
}

.ans-card.parasympathetic {
    border-color: var(--pns-light);
}

.ans-card.parasympathetic:hover {
    border-color: var(--pns-color);
}

.ans-card-header {
    padding: 20px 24px;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
}

.ans-card.sympathetic .ans-card-header {
    background: var(--sns-light);
}

.ans-card.parasympathetic .ans-card-header {
    background: var(--pns-light);
}

.ans-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    margin-bottom: 12px;
}

.sns-icon {
    background: var(--sns-color);
    color: white;
}

.pns-icon {
    background: var(--pns-color);
    color: white;
}

.ans-card-header h3 {
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.ans-tag {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.ans-card.sympathetic .ans-tag {
    background: var(--sns-color);
    color: white;
}

.ans-card.parasympathetic .ans-tag {
    background: var(--pns-color);
    color: white;
}

.ans-card-body {
    padding: 24px;
}

.ans-effects {
    list-style: none;
    padding: 0;
    margin-bottom: 20px;
}

.ans-effects li {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 0;
    font-size: 0.95rem;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--border-light);
}

.ans-effects li:last-child {
    border-bottom: none;
}

.ans-card.sympathetic .ans-effects li i {
    color: var(--sns-color);
}

.ans-card.parasympathetic .ans-effects li i {
    color: var(--pns-color);
}

.ans-visual {
    background: var(--bg-primary);
    border-radius: var(--radius);
    padding: 16px;
    text-align: center;
}

.ans-visual canvas {
    border-radius: var(--radius-sm);
    background: #1a2332;
}

.visual-label {
    display: block;
    margin-top: 8px;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.ans-balance-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px;
    text-align: center;
}

.ans-balance-card h4 {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.ans-balance-card h4 i {
    color: var(--accent);
}

.ans-balance-card p {
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.balance-meter {
    max-width: 500px;
    margin: 0 auto;
}

.balance-bar {
    height: 12px;
    background: linear-gradient(90deg, var(--sns-color) 0%, var(--bg-primary) 50%, var(--pns-color) 100%);
    border-radius: 6px;
    position: relative;
    margin-bottom: 12px;
}

.balance-indicator {
    position: absolute;
    top: -4px;
    left: 50%;
    transform: translateX(-50%);
    width: 20px;
    height: 20px;
    background: white;
    border: 3px solid var(--text-primary);
    border-radius: 50%;
    transition: left 0.3s ease;
}

.balance-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.sns-label { color: var(--sns-color); }
.pns-label { color: var(--pns-color); }

/* --- Equipment Section --- */
.equipment-lab {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

/* Equipment ECG Preview */
.equipment-ecg-preview {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.ecg-preview-header {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 20px;
    background: linear-gradient(135deg, var(--accent-light) 0%, #fff 100%);
    border-bottom: 1px solid var(--border);
    font-weight: 600;
    color: var(--text-primary);
}

.ecg-preview-header i {
    color: var(--accent);
    font-size: 1.1rem;
}

.equipment-ecg-preview canvas {
    display: block;
    width: 100%;
    height: 120px;
    background: linear-gradient(180deg, #1a2332 0%, #0f1419 100%);
}

.equipment-items-wrapper {
    display: grid;
    grid-template-columns: minmax(300px, 400px) 1fr;
    gap: 32px;
}

.equipment-bench {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
}

.equipment-item {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 20px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.equipment-item:hover {
    border-color: var(--accent-border);
    box-shadow: var(--shadow);
    transform: translateY(-2px);
}

.equipment-item.explored {
    border-color: var(--success);
    background: var(--success-light);
}

.equip-visual {
    width: 64px;
    height: 64px;
    margin: 0 auto 12px;
    background: var(--accent-light);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
}

.equip-visual i {
    font-size: 1.5rem;
    color: var(--accent);
}

.equipment-item.explored .equip-visual {
    background: var(--success-light);
}

.equipment-item.explored .equip-visual i {
    color: var(--success);
}

.equip-label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-primary);
}

.equip-check {
    position: absolute;
    top: 8px;
    right: 8px;
    width: 24px;
    height: 24px;
    background: var(--success);
    border-radius: 50%;
    display: none;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.75rem;
}

.equipment-item.explored .equip-check {
    display: flex;
}

.equipment-info-panel {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
    min-height: 400px;
}

.info-placeholder {
    text-align: center;
    padding: 60px 24px;
    color: var(--text-muted);
}

.info-placeholder i {
    font-size: 3rem;
    margin-bottom: 16px;
    color: var(--border);
}

.info-details h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border);
}

#equip-detail-body {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

#equip-detail-body p {
    margin-bottom: 12px;
}

.step-progress {
    margin-top: 24px;
    display: flex;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
}

.progress-bar {
    flex: 1;
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    min-width: 200px;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent) 0%, var(--success) 100%);
    border-radius: 3px;
    transition: width 0.3s ease;
    width: 0%;
}

.progress-text {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* --- Recording Section --- */
.recording-workspace {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.condition-panel {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
}

.condition-panel h3 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 20px;
}

.condition-panel h3 i {
    color: var(--accent);
}

.condition-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
}

.condition-card {
    background: var(--bg-primary);
    border: 2px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 20px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
}

.condition-card:hover {
    border-color: var(--accent-border);
    transform: translateY(-2px);
}

.condition-card.active {
    border-color: var(--accent);
    background: var(--accent-light);
}

.condition-icon {
    width: 48px;
    height: 48px;
    background: var(--bg-card);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 12px;
    font-size: 1.2rem;
    color: var(--text-muted);
    transition: var(--transition);
}

.condition-card.active .condition-icon {
    background: var(--accent);
    color: white;
}

.condition-card h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.condition-card p {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 12px;
}

.condition-hrv {
    display: inline-block;
    padding: 4px 12px;
    background: var(--bg-card);
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.condition-card.active .condition-hrv {
    background: white;
    color: var(--accent);
}

/* ECG Display Panel */
.ecg-display-panel {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.display-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 24px;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
}

.display-header h3 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1rem;
    font-weight: 600;
}

.display-header h3 i {
    color: var(--accent);
}

.monitor-controls {
    display: flex;
    align-items: center;
    gap: 24px;
}

/* Heart Beat Indicator */
.heart-beat-indicator {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: var(--accent-light);
    border-radius: 50%;
    margin-right: 12px;
    position: relative;
    box-shadow: 0 0 0 0 rgba(231, 76, 60, 0.4);
}

.heart-beat-indicator i {
    font-size: 1.8rem;
    color: var(--accent);
    transition: transform 0.1s ease-out, color 0.1s ease-out;
    z-index: 1;
}

.heart-beat-indicator.beating {
    animation: heartPulseGlow 0.3s ease-out;
}

.heart-beat-indicator.beating i {
    animation: heartBeatScale 0.3s ease-out;
}

@keyframes heartBeatScale {
    0% { transform: scale(1); }
    15% { transform: scale(1.35); }
    30% { transform: scale(1.1); }
    45% { transform: scale(1.25); }
    100% { transform: scale(1); }
}

@keyframes heartPulseGlow {
    0% { box-shadow: 0 0 0 0 rgba(231, 76, 60, 0.6); }
    50% { box-shadow: 0 0 20px 10px rgba(231, 76, 60, 0.3); }
    100% { box-shadow: 0 0 0 0 rgba(231, 76, 60, 0); }
}

.heart-rate-display,
.rr-display {
    display: flex;
    align-items: baseline;
    gap: 6px;
}

.hr-label,
.rr-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    font-weight: 500;
}

.hr-value,
.rr-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent);
    font-family: var(--font-mono);
}

.hr-unit,
.rr-unit {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.ecg-canvas-container {
    padding: 20px;
    position: relative;
}

.ecg-canvas-container canvas {
    width: 100%;
    height: auto;
    background: linear-gradient(180deg, #1a2332 0%, #0f1419 100%);
    border-radius: var(--radius);
}

.recording-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    padding: 20px;
    border-top: 1px solid var(--border);
}

.btn-record {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 14px 28px;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.btn-record:hover {
    background: var(--accent-dark);
    transform: translateY(-2px);
}

.btn-record i {
    animation: pulse-record 1.5s infinite;
}

@keyframes pulse-record {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.btn-stop {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 14px 28px;
    background: var(--danger);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.btn-stop:hover {
    background: #dc3545;
}

.record-timer {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 20px;
    background: var(--bg-primary);
    border-radius: var(--radius);
    font-family: var(--font-mono);
    font-weight: 600;
    color: var(--accent);
}

/* Tachogram Panel */
.tachogram-panel {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
}

.tachogram-panel h3 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.tachogram-panel h3 i {
    color: var(--accent);
}

.tachogram-panel canvas {
    width: 100%;
    height: auto;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 16px;
}

.tachogram-stats {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
}

.stat-item {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.stat-label {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.stat-value {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    font-family: var(--font-mono);
}

/* --- Analysis Section --- */
.analysis-workspace {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    margin-bottom: 24px;
}

.analysis-tabs {
    display: flex;
    border-bottom: 1px solid var(--border);
    background: var(--bg-primary);
}

.analysis-tab {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 16px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition);
    border-bottom: 3px solid transparent;
}

.analysis-tab:hover {
    color: var(--accent);
    background: var(--bg-card);
}

.analysis-tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
    background: var(--bg-card);
}

.analysis-panel {
    display: none;
    padding: 24px;
}

.analysis-panel.active {
    display: block;
}

/* Metrics Grid */
.metrics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 32px;
}

.metric-card {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 20px;
    text-align: center;
    transition: var(--transition);
}

.metric-card:hover {
    border-color: var(--accent-border);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.metric-card.highlight {
    border-color: var(--accent-border);
    background: var(--accent-light);
}

.metric-header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-bottom: 12px;
}

.metric-header h4 {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
}

.metric-header i {
    color: var(--text-muted);
    font-size: 0.8rem;
    cursor: help;
}

.metric-value {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--accent);
    font-family: var(--font-mono);
    margin-bottom: 8px;
}

.metric-desc {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.metric-reference {
    font-size: 0.75rem;
    color: var(--success);
    font-weight: 500;
}

/* Histogram */
.histogram-container {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
}

.histogram-container h4 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.histogram-container h4 i {
    color: var(--accent);
}

.histogram-container canvas {
    width: 100%;
    height: auto;
    background: white;
    border-radius: var(--radius);
}

/* Frequency Analysis */
.frequency-info {
    background: var(--accent-light);
    border-radius: var(--radius);
    padding: 16px;
    margin-bottom: 24px;
}

.frequency-info p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.spectrum-container {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 24px;
}

.spectrum-container canvas {
    width: 100%;
    height: auto;
    background: linear-gradient(180deg, #1a2332 0%, #0f1419 100%);
    border-radius: var(--radius);
    margin-bottom: 16px;
}

.frequency-bands {
    display: flex;
    justify-content: space-around;
}

.band-marker {
    text-align: center;
    padding: 8px 16px;
    border-radius: var(--radius);
}

.band-marker.vlf {
    background: #f0f0f0;
    color: var(--text-muted);
}

.band-marker.lf {
    background: var(--sns-light);
    color: var(--sns-color);
}

.band-marker.hf {
    background: var(--pns-light);
    color: var(--pns-color);
}

.band-range {
    font-size: 0.8rem;
    font-weight: 600;
}

.frequency-metrics {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 20px;
}

.freq-metric-card {
    background: var(--bg-primary);
    border: 2px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 20px;
    text-align: center;
    transition: var(--transition);
}

.freq-metric-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.freq-metric-card.lf-card {
    border-color: var(--sns-light);
}

.freq-metric-card.lf-card:hover {
    border-color: var(--sns-color);
}

.freq-metric-card.hf-card {
    border-color: var(--pns-light);
}

.freq-metric-card.hf-card:hover {
    border-color: var(--pns-color);
}

.freq-metric-card.ratio-card {
    border-color: var(--accent-border);
}

.freq-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 12px;
    font-size: 1rem;
}

.lf-card .freq-icon {
    background: var(--sns-light);
    color: var(--sns-color);
}

.hf-card .freq-icon {
    background: var(--pns-light);
    color: var(--pns-color);
}

.ratio-card .freq-icon {
    background: var(--accent-light);
    color: var(--accent);
}

.freq-metric-card h4 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.freq-value {
    font-size: 1.5rem;
    font-weight: 700;
    font-family: var(--font-mono);
    margin-bottom: 4px;
}

.lf-card .freq-value { color: var(--sns-color); }
.hf-card .freq-value { color: var(--pns-color); }
.ratio-card .freq-value { color: var(--accent); }

.freq-metric-card p {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.freq-desc {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* Poincaré Plot */
.nonlinear-info {
    background: var(--accent-light);
    border-radius: var(--radius);
    padding: 16px;
    margin-bottom: 24px;
}

.poincare-container {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
    text-align: center;
}

.poincare-container h4 {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.poincare-container h4 i {
    color: var(--accent);
}

.poincare-desc {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.poincare-container canvas {
    background: white;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 20px;
}

.poincare-metrics {
    display: flex;
    justify-content: center;
    gap: 32px;
    flex-wrap: wrap;
}

.poincare-stat {
    text-align: center;
}

.poincare-stat .stat-label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.poincare-stat .stat-value {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--accent);
    font-family: var(--font-mono);
}

.poincare-stat .stat-desc {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* --- Clinical Section --- */
.interpretation-section,
.applications-section,
.factors-section,
.results-summary {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px;
    margin-bottom: 24px;
}

.interpretation-section h3,
.applications-section h3,
.factors-section h3,
.results-summary h3 {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.interpretation-section h3 i,
.applications-section h3 i,
.factors-section h3 i,
.results-summary h3 i {
    color: var(--accent);
}

/* Interpretation Table */
.interpretation-table {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}

.interp-row {
    display: grid;
    grid-template-columns: 1fr 1fr 1.5fr;
    padding: 16px 20px;
    border-bottom: 1px solid var(--border);
    align-items: center;
}

.interp-row:last-child {
    border-bottom: none;
}

.interp-row.header {
    background: var(--bg-primary);
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-primary);
}

.interp-condition {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.9rem;
}

.interp-condition i {
    color: var(--accent);
}

.interp-hrv {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.interp-hrv.high {
    background: var(--pns-light);
    color: var(--pns-color);
}

.interp-hrv.low {
    background: var(--sns-light);
    color: var(--sns-color);
}

.interp-hrv.declining {
    background: var(--warning-light);
    color: var(--warning);
}

.interp-hrv.abnormal {
    background: var(--danger-light);
    color: var(--danger);
}

.interp-meaning {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* Applications Grid */
.applications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.app-card {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px;
    text-align: center;
    transition: var(--transition);
}

.app-card:hover {
    border-color: var(--accent-border);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.app-icon {
    width: 56px;
    height: 56px;
    background: var(--accent-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 1.3rem;
    color: var(--accent);
    transition: var(--transition);
}

.app-card:hover .app-icon {
    background: var(--accent);
    color: white;
}

.app-card h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.app-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Factors Grid */
.factors-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 16px;
}

.factor-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    padding: 20px;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    transition: var(--transition);
}

.factor-item:hover {
    border-color: var(--accent-border);
    transform: translateY(-2px);
}

.factor-item i {
    font-size: 1.5rem;
    color: var(--accent);
}

.factor-item span {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

/* Results Summary */
.summary-content {
    padding: 20px;
    background: var(--bg-primary);
    border-radius: var(--radius);
}

.no-data {
    text-align: center;
    color: var(--text-muted);
    padding: 20px;
}

/* Completion Section */
.completion-section {
    text-align: center;
    padding: 40px 0;
}

.completion-badge {
    margin-bottom: 24px;
}

.completion-badge i {
    font-size: 4rem;
    color: var(--success);
    margin-bottom: 16px;
}

.completion-badge h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.completion-badge p {
    color: var(--text-secondary);
}

/* --- Modal --- */
.modal {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 20px;
}

.modal-content {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    max-width: 600px;
    width: 100%;
    max-height: 80vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    border-bottom: 1px solid var(--border);
}

.modal-header h2 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.1rem;
    font-weight: 600;
}

.modal-header h2 i {
    color: var(--accent);
}

.modal-close {
    width: 36px;
    height: 36px;
    border: none;
    background: var(--bg-primary);
    border-radius: var(--radius);
    font-size: 1.5rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    transition: var(--transition);
}

.modal-close:hover {
    background: var(--danger-light);
    color: var(--danger);
}

.modal-body {
    padding: 24px;
    overflow-y: auto;
}

.glossary-search {
    position: relative;
    margin-bottom: 20px;
}

.glossary-search input {
    width: 100%;
    padding: 12px 16px 12px 44px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 0.95rem;
    transition: var(--transition);
}

.glossary-search input:focus {
    outline: none;
    border-color: var(--accent);
}

.glossary-search i {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

.glossary-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.glossary-item {
    padding: 16px;
    background: var(--bg-primary);
    border-radius: var(--radius);
    border-left: 3px solid var(--accent);
}

.glossary-item h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.glossary-item p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* --- Responsive --- */
@media (max-width: 992px) {
    #sidebar-nav {
        width: 72px;
    }
    
    .sidebar-header h2,
    .sidebar-header p,
    .lab-title,
    .step-content,
    .btn-glossary span {
        display: none;
    }
    
    .logo-image {
        max-height: 40px;
    }
    
    .nav-step {
        justify-content: center;
        padding: 12px;
    }
    
    #main-content {
        margin-left: 72px;
    }
    
    .equipment-lab {
        grid-template-columns: 1fr;
    }
    
    .ans-branches {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    #sidebar-nav {
        position: fixed;
        bottom: 0;
        top: auto;
        left: 0;
        right: 0;
        width: 100%;
        height: auto;
        max-height: 80px;
        flex-direction: row;
        border-top: 1px solid var(--border);
        border-right: none;
    }
    
    .sidebar-header,
    .sidebar-footer {
        display: none;
    }
    
    .nav-steps-vertical {
        display: flex;
        flex-direction: row;
        padding: 8px 4px;
        overflow-x: auto;
    }
    
    .nav-step {
        flex-direction: column;
        padding: 8px 12px;
        gap: 4px;
        min-width: auto;
        margin-bottom: 0;
    }
    
    .step-indicator {
        width: 32px;
        height: 32px;
    }
    
    .step-content {
        display: none;
    }
    
    #main-content {
        margin-left: 0;
        margin-bottom: 80px;
        padding: 20px;
    }
    
    .info-grid,
    .science-grid,
    .metrics-grid,
    .frequency-metrics,
    .applications-grid {
        grid-template-columns: 1fr;
    }
    
    .condition-cards {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .interp-row {
        grid-template-columns: 1fr;
        gap: 8px;
    }
    
    .interp-row.header {
        display: none;
    }
    
    /* Canvas responsiveness */
    canvas {
        max-width: 100%;
        height: auto !important;
    }
    
    .ecg-canvas-container canvas,
    .equipment-ecg-preview canvas {
        width: 100%;
        height: 150px !important;
    }
    
    /* Equipment section mobile */
    .equipment-items-wrapper {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    
    .equipment-bench {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
    }
    
    .equipment-item {
        padding: 14px 10px;
    }
    
    .equip-visual {
        width: 50px;
        height: 50px;
    }
    
    .equip-visual i {
        font-size: 1.2rem;
    }
    
    .equip-label {
        font-size: 0.75rem;
    }
    
    /* Monitor controls mobile */
    .display-header {
        flex-direction: column;
        gap: 12px;
        align-items: flex-start;
    }
    
    .monitor-controls {
        width: 100%;
        justify-content: space-between;
        gap: 12px;
    }
    
    .heart-beat-indicator {
        width: 44px;
        height: 44px;
    }
    
    .heart-beat-indicator i {
        font-size: 1.4rem;
    }
    
    .hr-value, .rr-value {
        font-size: 1.2rem;
    }
    
    /* Recording controls mobile */
    .recording-controls {
        flex-wrap: wrap;
        gap: 10px;
    }
    
    .btn-record, .btn-stop {
        flex: 1;
        min-width: 120px;
        padding: 12px 16px;
    }
    
    /* Analysis tabs mobile */
    .analysis-tabs {
        flex-wrap: wrap;
        gap: 6px;
    }
    
    .analysis-tab {
        flex: 1 1 calc(50% - 3px);
        min-width: 100px;
        padding: 10px;
        font-size: 0.8rem;
        justify-content: center;
    }
    
    /* Metrics cards mobile */
    .metric-card {
        padding: 14px;
    }
    
    .metric-value {
        font-size: 1.3rem;
    }
    
    /* Frequency metrics mobile */
    .freq-metric-card {
        padding: 14px;
    }
    
    .freq-value {
        font-size: 1.2rem;
    }
    
    /* Poincare plot mobile */
    .poincare-container canvas {
        max-width: 280px;
        height: 280px !important;
        margin: 0 auto;
        display: block;
    }
    
    .poincare-metrics {
        flex-wrap: wrap;
        gap: 12px;
    }
    
    .poincare-stat {
        flex: 1 1 calc(33% - 8px);
        min-width: 80px;
    }
    
    /* Clinical section mobile */
    .applications-grid {
        grid-template-columns: 1fr;
    }
    
    .app-card {
        padding: 16px;
    }
    
    .factors-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
    }
    
    .factor-item {
        padding: 12px;
        font-size: 0.8rem;
    }
    
    /* Tachogram mobile */
    .tachogram-panel canvas {
        height: 100px !important;
    }
    
    .tachogram-stats {
        flex-wrap: wrap;
        gap: 8px;
    }
    
    .tachogram-stats .stat-item {
        flex: 1 1 calc(50% - 4px);
        min-width: 80px;
    }
    
    /* Welcome section mobile */
    .welcome-card {
        padding: 24px 16px;
    }
    
    .welcome-card h1 {
        font-size: 1.5rem;
    }
    
    .welcome-ecg canvas {
        height: 100px !important;
    }
    
    /* ANS section mobile */
    .ans-branches {
        gap: 16px;
    }
    
    .branch-card {
        padding: 16px;
    }
    
    .branch-card canvas {
        height: 80px !important;
    }
    
    /* Completion section mobile */
    .completion-badge {
        padding: 24px 16px;
    }
    
    .completion-badge i {
        font-size: 3rem;
    }
    
    /* Modal mobile */
    .modal-content {
        width: calc(100% - 32px);
        max-height: 80vh;
        margin: 16px;
    }
    
    .modal-header,
    .modal-body {
        padding: 16px;
    }
}

@media (max-width: 480px) {
    #main-content {
        padding: 12px;
        margin-bottom: 70px;
    }
    
    .step-container {
        padding: 0;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }
    
    .section-header h2 {
        font-size: 1.1rem;
    }
    
    .section-header p {
        font-size: 0.8rem;
    }
    
    .section-header > i {
        font-size: 1.5rem;
        width: 44px;
        height: 44px;
    }
    
    /* Navigation mobile small */
    .nav-step {
        padding: 6px 8px;
    }
    
    .nav-step .step-indicator {
        width: 26px;
        height: 26px;
        font-size: 0.65rem;
    }
    
    /* Cards mobile small */
    .info-card,
    .metric-card,
    .branch-card,
    .app-card {
        padding: 12px;
    }
    
    /* Buttons mobile small */
    .btn-primary {
        padding: 10px 16px;
        font-size: 0.85rem;
    }
    
    .btn-record, .btn-stop {
        padding: 10px 14px;
        font-size: 0.8rem;
    }
    
    /* Equipment mobile small */
    .equipment-bench {
        gap: 8px;
    }
    
    .equipment-item {
        padding: 10px 8px;
    }
    
    .equip-visual {
        width: 44px;
        height: 44px;
    }
    
    .equip-visual i {
        font-size: 1rem;
    }
    
    .equip-label {
        font-size: 0.7rem;
    }
    
    /* Condition cards mobile small */
    .condition-cards {
        grid-template-columns: 1fr 1fr;
        gap: 8px;
    }
    
    .condition-card {
        padding: 10px;
    }
    
    .condition-icon {
        font-size: 1.2rem;
    }
    
    .condition-card h4 {
        font-size: 0.8rem;
    }
    
    .condition-card p {
        font-size: 0.65rem;
    }
    
    .condition-hrv {
        font-size: 0.6rem;
        padding: 3px 6px;
    }
    
    /* Monitor mobile small */
    .monitor-controls {
        gap: 8px;
    }
    
    .heart-beat-indicator {
        width: 38px;
        height: 38px;
    }
    
    .heart-beat-indicator i {
        font-size: 1.2rem;
    }
    
    .hr-value, .rr-value {
        font-size: 1rem;
    }
    
    .hr-label, .rr-label, .hr-unit, .rr-unit {
        font-size: 0.7rem;
    }
    
    /* Analysis mobile small */
    .analysis-tab {
        flex: 1 1 100%;
        padding: 8px;
    }
    
    .metric-value {
        font-size: 1.1rem;
    }
    
    .metric-desc {
        font-size: 0.7rem;
    }
    
    /* Factors mobile small */
    .factors-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .factor-item {
        padding: 10px;
        font-size: 0.75rem;
    }
    
    .factor-item i {
        font-size: 1rem;
    }
    
    /* Welcome mobile small */
    .welcome-card h1 {
        font-size: 1.25rem;
    }
    
    .learning-outcomes li {
        font-size: 0.8rem;
        padding: 8px 12px;
    }
    
    /* Glossary mobile */
    .glossary-term {
        padding: 12px;
    }
    
    .glossary-term h4 {
        font-size: 0.9rem;
    }
}