/* Medical/Healthcare Professional Design for Acute Rejection Community */
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary: #10b981;
    --accent: #f59e0b;
    --medical-blue: #0ea5e9;
    --medical-green: #059669;
    --medical-red: #dc2626;
    --background: #ffffff;
    --surface: #f8fafc;
    --surface-2: #f1f5f9;
    --text: #1f2937;
    --text-muted: #6b7280;
    --text-light: #9ca3af;
    --border: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset and base styles */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text);
    background: var(--background);
    font-size: 16px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 0.5em;
    color: var(--text);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: 1rem;
    color: var(--text-muted);
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--primary-dark);
}

/* Layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header and Navigation */
.navbar {
    background: var(--background);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--border);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-logo h1 {
    color: var(--primary);
    font-size: 1.5rem;
    margin-bottom: 0;
}

.nav-logo .tagline {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 400;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
    background: var(--surface);
    color: var(--primary);
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 0.25rem;
}

.hamburger span {
    width: 1.5rem;
    height: 2px;
    background: var(--text);
    transition: var(--transition);
}

/* Hero Section */
.hero {
    padding: 4rem 1rem;
    background: linear-gradient(135deg, var(--surface) 0%, var(--surface-2) 100%);
    display: flex;
    align-items: center;
    min-height: 60vh;
}

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

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--primary);
}

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

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.hero-visual {
    display: flex;
    justify-content: center;
    margin-top: 2rem;
}

.medical-icon {
    opacity: 0.8;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    font-weight: 600;
    text-align: center;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

.btn.primary:hover {
    background: var(--primary-dark);
    color: white;
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

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

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

.btn.large {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

/* Sections */
section {
    padding: 4rem 0;
}

.section-title {
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text);
}

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

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.feature-card {
    background: var(--surface);
    padding: 2rem;
    border-radius: 1rem;
    text-align: center;
    transition: var(--transition);
    border: 1px solid var(--border);
}

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

.feature-icon {
    color: var(--primary);
    margin-bottom: 1rem;
    display: flex;
    justify-content: center;
}

.feature-card h3 {
    color: var(--text);
    margin-bottom: 1rem;
}

.feature-card p {
    color: var(--text-muted);
}

/* Testimonials */
.testimonials {
    background: var(--surface);
}

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

.testimonial-card {
    background: var(--background);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow-md);
    border-left: 4px solid var(--secondary);
}

.quote {
    font-style: italic;
    margin-bottom: 1rem;
    color: var(--text);
    font-size: 1.125rem;
}

.author {
    color: var(--text-muted);
    font-weight: 600;
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    text-align: center;
}

.cta-content h2 {
    color: white;
    margin-bottom: 1rem;
}

.cta-content p {
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 2rem;
    font-size: 1.125rem;
}

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

.cta-section .btn.primary:hover {
    background: var(--surface);
}

/* Footer */
footer {
    background: var(--text);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    color: white;
    margin-bottom: 1rem;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.8);
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: rgba(255, 255, 255, 0.8);
    transition: var(--transition);
}

.footer-section ul li a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    padding-top: 2rem;
    text-align: center;
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 0.5rem;
}

/* Contact Form */
.contact-form {
    background: var(--surface);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow-md);
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group textarea {
    min-height: 120px;
    resize: vertical;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .hamburger {
        display: flex;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .features-grid,
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    section {
        padding: 2rem 0;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 0.5rem;
    }
    
    .hero {
        padding: 2rem 1rem;
    }
    
    .feature-card,
    .testimonial-card {
        padding: 1.5rem;
    }
}

/* Accessibility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Focus styles */
button:focus,
a:focus,
input:focus,
textarea:focus {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* Print styles */
@media print {
    .navbar,
    .hamburger,
    .cta-section,
    footer {
        display: none;
    }
    
    body {
        font-size: 12pt;
    }
    
    .hero {
        page-break-inside: avoid;
    }
}