/* ========================
   Global Styles & Reset
   ======================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Primary Colors */
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #8b5cf6;
    --secondary-light: #a78bfa;
    
    /* Accent Colors */
    --accent-yellow: #fbbf24;
    --accent-green: #10b981;
    --accent-red: #ef4444;
    --accent-pink: #ec4899;
    
    /* Neutral Colors */
    --white: #ffffff;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #6366f1, #8b5cf6);
    --gradient-secondary: linear-gradient(135deg, #8b5cf6, #a78bfa);
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    /* Transitions */
    --transition: all 0.3s ease;
}

body {
    font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--gray-800);
    background: var(--gray-50);
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Poppins', sans-serif;
    font-weight: 700;
    line-height: 1.2;
    color: var(--gray-900);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 15px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--gray-600);
    font-weight: 500;
}

/* ========================
   Navigation
   ======================== */
.navbar {
    background: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 15px 0;
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.logo i {
    font-size: 2rem;
    animation: pulse-brain 2s ease-in-out infinite;
}

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

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: var(--gray-700);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: var(--transition);
}

.nav-links a:hover {
    color: var(--primary);
}

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

/* ========================
   Hero Section
   ======================== */
.hero {
    background: linear-gradient(135deg, #f0f9ff 0%, #e0e7ff 100%);
    padding: 100px 0 80px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" fill="none"/><path d="M0 50 Q 25 25 50 50 T 100 50" stroke="rgba(99, 102, 241, 0.05)" stroke-width="1" fill="none"/></svg>');
    opacity: 0.5;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-text {
    animation: fadeInLeft 1s ease-out;
}

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.badge {
    display: inline-block;
    background: var(--gradient-primary);
    color: var(--white);
    padding: 8px 20px;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 20px;
}

.hero-title {
    font-size: 3rem;
    margin-bottom: 20px;
    line-height: 1.1;
}

.hero-tagline {
    font-size: 1.3rem;
    color: var(--gray-700);
    margin-bottom: 20px;
    font-weight: 500;
}

.hero-description {
    font-size: 1.1rem;
    color: var(--gray-600);
    line-height: 1.8;
    margin-bottom: 30px;
}

.hero-stats {
    display: flex;
    gap: 40px;
    margin-top: 40px;
}

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

.stat-number {
    font-size: 2.5rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    color: var(--gray-600);
    font-size: 0.9rem;
    font-weight: 500;
}

.hero-visual {
    animation: fadeInRight 1s ease-out;
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.brain-animation {
    position: relative;
    filter: drop-shadow(0 20px 40px rgba(99, 102, 241, 0.2));
}

.animated-brain {
    width: 100%;
    max-width: 400px;
    height: auto;
}

.brain-left, .brain-right {
    animation: breathe 4s ease-in-out infinite;
}

.brain-right {
    animation-delay: 0.5s;
}

@keyframes breathe {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.02); }
}

.pulse-1, .pulse-2, .pulse-3, .pulse-4 {
    animation: pulse-region 3s ease-in-out infinite;
}

.pulse-2 { animation-delay: 0.5s; }
.pulse-3 { animation-delay: 1s; }
.pulse-4 { animation-delay: 1.5s; }

@keyframes pulse-region {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 0.7; }
}

.neural-line {
    animation: neural-flow 2s ease-in-out infinite;
}

@keyframes neural-flow {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 0.8; }
}

.energy-particle {
    animation: particle-move 3s ease-in-out infinite;
}

@keyframes particle-move {
    0%, 100% { opacity: 0; transform: scale(0); }
    50% { opacity: 1; transform: scale(1); }
}

.brain-pulse {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 80%;
    height: 80%;
    border: 3px solid var(--primary-light);
    border-radius: 50%;
    opacity: 0;
    animation: pulse-wave 3s ease-out infinite;
}

@keyframes pulse-wave {
    0% {
        transform: translate(-50%, -50%) scale(0.8);
        opacity: 0.8;
    }
    100% {
        transform: translate(-50%, -50%) scale(1.5);
        opacity: 0;
    }
}

/* ========================
   Location Section
   ======================== */
.location-section {
    background: var(--white);
}

.location-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.skull-diagram {
    background: linear-gradient(135deg, #f0f9ff, #e0e7ff);
    border-radius: 20px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
}

.skull-svg {
    width: 100%;
    max-width: 300px;
    height: auto;
}

.info-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.info-item {
    display: flex;
    gap: 20px;
    align-items: flex-start;
    background: var(--gray-50);
    padding: 20px;
    border-radius: 15px;
    transition: var(--transition);
    border-left: 4px solid var(--primary);
}

.info-item:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow-md);
}

.icon-box {
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    color: var(--white);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    flex-shrink: 0;
}

.info-item strong {
    color: var(--primary);
    display: block;
    margin-bottom: 5px;
}

/* ========================
   Structure Section
   ======================== */
.structure-section {
    background: linear-gradient(135deg, #faf5ff 0%, #f3e8ff 100%);
}

.interactive-diagram {
    background: var(--white);
    border-radius: 20px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 60px;
}

.diagram-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
}

.brain-diagram {
    width: 100%;
    max-width: 600px;
}

.brain-part {
    cursor: pointer;
    transition: var(--transition);
}

.brain-part:hover {
    filter: brightness(1.2);
    stroke-width: 4;
}

.label-text {
    font-size: 14px;
    font-weight: 600;
    fill: var(--gray-700);
}

.label-text.small {
    font-size: 12px;
}

.label-line {
    stroke: var(--gray-400);
    stroke-width: 1;
}

.diagram-info {
    background: linear-gradient(135deg, #f0f9ff, #e0e7ff);
    padding: 30px;
    border-radius: 15px;
    min-height: 200px;
}

.diagram-info h3 {
    color: var(--primary);
    margin-bottom: 15px;
    font-size: 1.5rem;
}

.diagram-info p {
    color: var(--gray-700);
    line-height: 1.8;
}

.structure-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.structure-card {
    background: var(--white);
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-top: 4px solid var(--primary);
}

.structure-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.card-icon {
    width: 70px;
    height: 70px;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: var(--white);
    margin-bottom: 20px;
}

.structure-card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: var(--gray-900);
}

.structure-card p {
    color: var(--gray-600);
    line-height: 1.8;
    margin-bottom: 10px;
}

.structure-card p strong {
    color: var(--primary);
}

/* ========================
   Functions Section
   ======================== */
.functions-section {
    background: var(--white);
}

.functions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.function-category {
    background: var(--gray-50);
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.function-category:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.category-header {
    padding: 25px;
    color: var(--white);
    text-align: center;
}

.category-header i {
    font-size: 2.5rem;
    display: block;
    margin-bottom: 10px;
}

.category-header h3 {
    font-size: 1.3rem;
    color: var(--white);
}

.function-items {
    padding: 25px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.function-item {
    display: flex;
    gap: 15px;
    align-items: flex-start;
    padding: 15px;
    background: var(--white);
    border-radius: 12px;
    transition: var(--transition);
}

.function-item:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow);
}

.function-item i {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, #e0e7ff, #ddd6fe);
    color: var(--primary);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.function-item strong {
    display: block;
    color: var(--gray-800);
    margin-bottom: 3px;
}

.function-item p {
    color: var(--gray-600);
    font-size: 0.9rem;
}

/* ========================
   How Brain Works Section
   ======================== */
.how-works-section {
    background: linear-gradient(135deg, #ecfdf5 0%, #d1fae5 100%);
}

.neuron-animation-container {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 50px;
    background: var(--white);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 50px;
}

.neuron-info h3 {
    color: var(--primary);
    margin-bottom: 25px;
    font-size: 1.8rem;
}

.neuron-parts {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.neuron-part-item {
    display: flex;
    gap: 15px;
    align-items: flex-start;
}

.part-icon {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.1rem;
    flex-shrink: 0;
}

.neuron-part-item strong {
    display: block;
    color: var(--gray-800);
    margin-bottom: 3px;
}

.neuron-part-item p {
    color: var(--gray-600);
    font-size: 0.95rem;
}

.neuron-visual {
    background: linear-gradient(135deg, #f0f9ff, #e0e7ff);
    padding: 30px;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.neuron-svg {
    width: 100%;
    max-width: 600px;
}

.signal-process {
    background: var(--white);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 50px;
}

.signal-process h3 {
    color: var(--primary);
    margin-bottom: 30px;
    font-size: 1.8rem;
    text-align: center;
}

.process-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 25px;
}

.process-step {
    background: linear-gradient(135deg, #f0f9ff, #e0e7ff);
    padding: 25px;
    border-radius: 15px;
    text-align: center;
    transition: var(--transition);
    position: relative;
}

.process-step:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.step-number {
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 auto 15px;
}

.step-content h4 {
    color: var(--gray-800);
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.step-content p {
    color: var(--gray-600);
    font-size: 0.95rem;
    line-height: 1.6;
}

.cns-info {
    background: var(--white);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
}

.cns-info h3 {
    color: var(--primary);
    margin-bottom: 30px;
    font-size: 1.8rem;
    text-align: center;
}

.cns-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

.cns-item {
    background: linear-gradient(135deg, #f0f9ff, #e0e7ff);
    padding: 30px;
    border-radius: 15px;
    text-align: center;
    flex: 1;
    min-width: 200px;
    max-width: 250px;
}

.cns-item i {
    font-size: 3rem;
    color: var(--primary);
    display: block;
    margin-bottom: 15px;
}

.cns-item h4 {
    color: var(--gray-800);
    margin-bottom: 10px;
    font-size: 1.3rem;
}

.cns-item p {
    color: var(--gray-600);
    font-size: 0.95rem;
}

.cns-connector {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
}

/* ========================
   Brain Areas Section
   ======================== */
.brain-areas-section {
    background: var(--white);
}

.brain-areas-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.brain-area-card {
    background: linear-gradient(135deg, #ffffff, #f9fafb);
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-left: 5px solid var(--primary);
}

.brain-area-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.area-icon {
    width: 70px;
    height: 70px;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: var(--white);
    margin-bottom: 20px;
}

.brain-area-card h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: var(--gray-900);
}

.brain-area-card p {
    color: var(--gray-600);
    line-height: 1.8;
}

/* ========================
   Disorders Section
   ======================== */
.disorders-section {
    background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
}

.disorders-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.disorder-card {
    background: var(--white);
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

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

.disorder-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, #fef3c7, #fde68a);
    color: #f59e0b;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin-bottom: 20px;
}

.disorder-card h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: var(--gray-900);
}

.disorder-content p {
    color: var(--gray-600);
    line-height: 1.8;
    margin-bottom: 10px;
}

.disorder-content strong {
    color: var(--gray-800);
}

.safety-note {
    background: linear-gradient(135deg, #fee2e2, #fecaca);
    padding: 30px;
    border-radius: 20px;
    display: flex;
    gap: 20px;
    align-items: flex-start;
    border-left: 5px solid var(--accent-red);
}

.safety-note i {
    font-size: 2rem;
    color: var(--accent-red);
    flex-shrink: 0;
}

.safety-note p {
    color: var(--gray-700);
    font-size: 1.05rem;
    line-height: 1.8;
}

.safety-note strong {
    color: var(--accent-red);
}

/* ========================
   Health Tips Section
   ======================== */
.health-section {
    background: var(--white);
}

.health-tips-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.health-tip {
    background: linear-gradient(135deg, #ffffff, #f9fafb);
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    text-align: center;
}

.health-tip:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: var(--shadow-xl);
}

.tip-icon {
    width: 80px;
    height: 80px;
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    color: var(--white);
    margin: 0 auto 20px;
}

.health-tip h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--gray-900);
}

.health-tip p {
    color: var(--gray-600);
    line-height: 1.8;
}

/* ========================
   Fun Facts Section
   ======================== */
.fun-facts-section {
    background: linear-gradient(135deg, #fae8ff 0%, #f3e8ff 100%);
}

.facts-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.fact-card {
    background: var(--white);
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    display: flex;
    gap: 20px;
    align-items: flex-start;
    position: relative;
    overflow: hidden;
}

.fact-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 5px;
    height: 100%;
    background: var(--gradient-primary);
}

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

.fact-number {
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    color: var(--white);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    font-weight: 700;
    flex-shrink: 0;
}

.fact-content {
    flex: 1;
}

.fact-content i {
    font-size: 2rem;
    color: var(--primary-light);
    display: block;
    margin-bottom: 10px;
}

.fact-content p {
    color: var(--gray-700);
    line-height: 1.8;
}

.fact-content strong {
    color: var(--primary);
}

/* ========================
   Quiz Section
   ======================== */
.quiz-section {
    background: var(--white);
}

.quiz-container {
    max-width: 800px;
    margin: 0 auto;
}

.quiz-question {
    background: linear-gradient(135deg, #ffffff, #f9fafb);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 30px;
}

.quiz-question h3 {
    color: var(--primary);
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.question-text {
    font-size: 1.2rem;
    color: var(--gray-800);
    margin-bottom: 25px;
    font-weight: 500;
}

.options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.option {
    background: var(--white);
    border: 2px solid var(--gray-300);
    padding: 15px 20px;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 500;
    color: var(--gray-700);
    cursor: pointer;
    transition: var(--transition);
    text-align: left;
}

.option:hover {
    border-color: var(--primary);
    background: var(--gray-50);
    transform: translateY(-2px);
}

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

.option.correct {
    background: var(--accent-green);
    color: var(--white);
    border-color: var(--accent-green);
}

.option.wrong {
    background: var(--accent-red);
    color: var(--white);
    border-color: var(--accent-red);
}

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

.feedback {
    margin-top: 20px;
    padding: 15px;
    border-radius: 10px;
    font-weight: 500;
    display: none;
}

.feedback.show {
    display: block;
}

.feedback.correct {
    background: #d1fae5;
    color: #065f46;
}

.feedback.wrong {
    background: #fee2e2;
    color: #991b1b;
}

.quiz-results {
    background: var(--gradient-primary);
    padding: 50px;
    border-radius: 20px;
    text-align: center;
    color: var(--white);
    display: none;
}

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

.quiz-results h3 {
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: var(--white);
}

.quiz-results #score {
    font-size: 4rem;
    font-weight: 800;
}

.quiz-results p {
    font-size: 1.3rem;
    margin-bottom: 30px;
}

.btn-retry {
    background: var(--white);
    color: var(--primary);
    padding: 15px 40px;
    border: none;
    border-radius: 50px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.btn-retry:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

/* ========================
   NEET Notes Section
   ======================== */
.neet-section {
    background: linear-gradient(135deg, #dbeafe 0%, #bfdbfe 100%);
}

.neet-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.neet-card {
    background: var(--white);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    border-top: 5px solid var(--primary);
}

.neet-icon {
    width: 70px;
    height: 70px;
    background: var(--gradient-primary);
    color: var(--white);
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin-bottom: 20px;
}

.neet-card h3 {
    font-size: 1.5rem;
    margin-bottom: 25px;
    color: var(--gray-900);
}

.neet-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.neet-list li {
    padding-left: 25px;
    position: relative;
    color: var(--gray-700);
    line-height: 1.8;
}

.neet-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--primary);
    font-weight: 700;
}

.neet-list strong {
    color: var(--primary);
}

.memory-tricks {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.trick-item {
    background: linear-gradient(135deg, #f0f9ff, #e0e7ff);
    padding: 20px;
    border-radius: 12px;
    border-left: 4px solid var(--primary);
}

.trick-item strong {
    display: block;
    color: var(--primary);
    margin-bottom: 8px;
    font-size: 1.05rem;
}

.trick-item p {
    color: var(--gray-700);
    line-height: 1.8;
}

.trick-item em {
    color: var(--secondary);
    font-weight: 600;
}

/* ========================
   Footer
   ======================== */
.footer {
    background: var(--gray-900);
    color: var(--gray-300);
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3, .footer-section h4 {
    color: var(--white);
    margin-bottom: 20px;
}

.footer-section h3 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
}

.footer-section p {
    line-height: 1.8;
}

.footer-section ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-section a {
    color: var(--gray-400);
    text-decoration: none;
    transition: var(--transition);
}

.footer-section a:hover {
    color: var(--primary-light);
    padding-left: 5px;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid var(--gray-800);
}

/* ========================
   Responsive Design
   ======================== */
@media (max-width: 968px) {
    .hero-content,
    .location-content,
    .diagram-container,
    .neuron-animation-container {
        grid-template-columns: 1fr;
    }
    
    .hero-visual,
    .location-visual {
        text-align: center;
    }
    
    .animated-brain,
    .skull-svg {
        max-width: 350px;
    }
    
    .nav-links {
        gap: 15px;
        font-size: 0.9rem;
    }
    
    .hero-title {
        font-size: 2.2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
}

@media (max-width: 768px) {
    .section {
        padding: 60px 0;
    }
    
    .hero {
        padding: 80px 0 60px;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }
    
    .nav-links {
        display: none;
    }
    
    .hero-title {
        font-size: 1.8rem;
    }
    
    .hero-tagline {
        font-size: 1.1rem;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .functions-grid,
    .health-tips-grid,
    .brain-areas-grid {
        grid-template-columns: 1fr;
    }
    
    .cns-content {
        flex-direction: column;
    }
    
    .cns-connector {
        transform: rotate(90deg);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero-title {
        font-size: 1.5rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .badge {
        font-size: 0.8rem;
        padding: 6px 15px;
    }
    
    .structure-cards,
    .disorders-grid,
    .facts-container {
        grid-template-columns: 1fr;
    }
    
    .quiz-question {
        padding: 25px;
    }
    
    .options {
        grid-template-columns: 1fr;
    }
}

/* ========================
   Animations
   ======================== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.8s ease-out;
}

/* Smooth Scroll */
html {
    scroll-behavior: smooth;
}

/* Selection Color */
::selection {
    background: var(--primary-light);
    color: var(--white);
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 12px;
}

::-webkit-scrollbar-track {
    background: var(--gray-100);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-light);
    border-radius: 6px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary);
}