/* Base Variables */
:root {
    /* Light Mode Colors - Medical Theme */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafb;
    --bg-tertiary: #f0f4f5;
    --text-primary: #1a1a1a;
    --text-secondary: #4a5568;
    --text-tertiary: #718096;
    
    /* Medical Theme Colors */
    --medical-blue: #0066cc;
    --medical-green: #00a86b;
    --medical-teal: #008b8b;
    --medical-red: #dc143c;
    --accent-primary: #0066cc;
    --accent-secondary: #00a86b;
    --accent-hover: #0052a3;
    
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;
    
    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-tamil: 'Noto Sans Tamil', sans-serif;
    --font-weight-light: 300;
    --font-weight-regular: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: all 0.15s ease;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode */
body.dark-mode {
    --bg-primary: #0f1419;
    --bg-secondary: #1a1f2a;
    --bg-tertiary: #232937;
    --text-primary: #ffffff;
    --text-secondary: #cbd5e0;
    --text-tertiary: #a0aec0;
    
    /* Medical Theme Colors - Dark Mode */
    --medical-blue: #4da6ff;
    --medical-green: #00d084;
    --medical-teal: #00b8b8;
    --medical-red: #ff6b6b;
    --accent-primary: #4da6ff;
    --accent-secondary: #00d084;
    --accent-hover: #66b3ff;
    
    --border-color: #2d3748;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: var(--transition);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Tamil Language Support */
body.tamil {
    font-family: var(--font-tamil);
}

body.tamil .nav-logo,
body.tamil h1,
body.tamil h2,
body.tamil h3,
body.tamil h4 {
    font-family: var(--font-tamil);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* Navigation */
.nav-container {
    position: fixed;
    top: 0;
    width: 100%;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    backdrop-filter: blur(10px);
    background: rgba(var(--bg-primary), 0.95);
    box-shadow: var(--shadow-sm);
}

.nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.5rem;
    font-weight: var(--font-weight-bold);
    color: var(--text-primary);
}

.logo-symbol {
    font-size: 1.75rem;
}

.nav-links {
    display: flex;
    gap: var(--spacing-lg);
    align-items: center;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: var(--font-weight-medium);
    font-size: 0.95rem;
    transition: var(--transition);
    position: relative;
    padding: var(--spacing-xs) 0;
}

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

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

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

/* Toggle Buttons */
.nav-toggles {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

.toggle-btn {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: 1rem;
    color: var(--text-primary);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
}

.toggle-btn:hover {
    background: var(--bg-tertiary);
    border-color: var(--accent-primary);
}

.toggle-label {
    font-weight: var(--font-weight-semibold);
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* Hero Section */
.hero {
    padding-top: calc(80px + var(--spacing-3xl));
    padding-bottom: var(--spacing-3xl);
    min-height: 80vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: -1;
}

.medical-pattern {
    position: absolute;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 80%, var(--medical-blue) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, var(--medical-green) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, var(--medical-teal) 0%, transparent 50%);
    opacity: 0.05;
}

.gradient-overlay {
    position: absolute;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, 
        rgba(var(--bg-primary), 0.9) 0%, 
        rgba(var(--bg-primary), 0.7) 100%);
}

.hero-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.coming-soon-badge {
    display: inline-block;
    background: var(--medical-green);
    color: white;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-lg);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: var(--font-weight-extrabold);
    margin-bottom: var(--spacing-md);
    line-height: 1.2;
    background: linear-gradient(135deg, var(--medical-blue) 0%, var(--medical-green) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1.25rem, 2.5vw, 1.75rem);
    font-weight: var(--font-weight-light);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

.hero-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* Sections */
section {
    padding: var(--spacing-3xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.section-header h2 {
    font-size: clamp(2rem, 3vw, 2.5rem);
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-md);
}

.section-header p {
    font-size: 1.125rem;
    color: var(--text-secondary);
}

/* Features Grid */
.features {
    background: var(--bg-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

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

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-primary);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
    display: block;
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-sm);
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* About Section */
.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-2xl);
    align-items: center;
}

.about-text h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-lg);
}

.about-text p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

.about-values {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.value-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.value-icon {
    color: var(--medical-green);
    font-size: 1.25rem;
}

.about-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.image-placeholder {
    width: 100%;
    max-width: 400px;
    aspect-ratio: 1;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 6rem;
    opacity: 0.5;
}

/* Newsletter Section */
.newsletter {
    background: var(--bg-secondary);
}

.newsletter-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.newsletter-content h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
}

.newsletter-content > p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
}

.newsletter-form {
    margin-bottom: var(--spacing-md);
}

.form-group {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.form-input {
    flex: 1;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 1rem;
    transition: var(--transition);
}

.form-input:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(var(--accent-primary), 0.1);
}

.form-options {
    display: flex;
    justify-content: center;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    cursor: pointer;
    color: var(--text-secondary);
}

.checkbox-label input[type="checkbox"] {
    cursor: pointer;
}

.form-message {
    margin-top: var(--spacing-md);
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
    display: none;
}

.form-message.success {
    background: rgba(var(--medical-green), 0.1);
    color: var(--medical-green);
    display: block;
}

.form-message.error {
    background: rgba(var(--medical-red), 0.1);
    color: var(--medical-red);
    display: block;
}

/* Footer */
.footer {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
}

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

.footer-section h3,
.footer-section h4 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: var(--spacing-xs);
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
}

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

.social-links {
    display: flex;
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--accent-primary);
    color: white;
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    color: var(--text-tertiary);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-md);
    font-weight: var(--font-weight-medium);
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

.btn-primary {
    background: var(--accent-primary);
    color: white;
}

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: transparent;
    color: var(--accent-primary);
    border: 2px solid var(--accent-primary);
}

.btn-secondary:hover {
    background: var(--accent-primary);
    color: white;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero-cta {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .about-content {
        grid-template-columns: 1fr;
    }
    
    .about-image {
        order: -1;
    }
    
    .form-group {
        flex-direction: column;
    }
    
    .form-input,
    .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .nav-inner {
        padding: var(--spacing-sm);
    }
    
    .container {
        padding: 0 var(--spacing-md);
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .feature-card {
        padding: var(--spacing-lg);
    }
}