/* ===== RESET & BASE ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --primary: #0d9488;
    --primary-dark: #0f766e;
    --primary-light: #14b8a6;
    --accent: #06b6d4;
    --dark: #0a0f14;
    --gray-900: #111820;
    --gray-800: #1e2a35;
    --gray-700: #334155;
    --gray-600: #475569;
    --gray-500: #64748b;
    --gray-400: #94a3b8;
    --gray-300: #cbd5e1;
    --gray-200: #e2e8f0;
    --gray-100: #f1f5f9;
    --gray-50: #f8fafc;
    --white: #ffffff;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow: 0 4px 12px rgba(0,0,0,0.1);
    --shadow-lg: 0 12px 40px rgba(0,0,0,0.15);
    --radius: 8px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
}

html { scroll-behavior: smooth; }
body {
    font-family: 'Inter', -apple-system, sans-serif;
    color: var(--gray-600);
    line-height: 1.6;
    background: var(--white);
    -webkit-font-smoothing: antialiased;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }
img { max-width: 100%; height: auto; display: block; }

/* ===== BUTTONS ===== */
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 14px 28px; border-radius: var(--radius); font-weight: 600;
    font-size: 0.9rem; cursor: pointer; transition: var(--transition); border: none;
}
.btn-primary { background: var(--primary); color: var(--white); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(13,148,136,0.35); }
.btn-outline { background: transparent; color: var(--white); border: 2px solid rgba(255,255,255,0.3); }
.btn-outline:hover { background: var(--white); color: var(--dark); }
.btn-white { background: var(--white); color: var(--dark); }
.btn-white:hover { background: var(--gray-100); transform: translateY(-1px); }
.btn-lg { padding: 16px 32px; font-size: 0.95rem; }
.btn-full { width: 100%; }

/* ===== HEADER ===== */
.header {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(255,255,255,0.98); backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--gray-200);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.logo { font-size: 1.3rem; font-weight: 800; color: var(--dark); letter-spacing: -0.03em; }
.logo span { color: var(--primary); }
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a { font-weight: 500; color: var(--gray-600); font-size: 0.9rem; }
.nav-links a:hover { color: var(--primary); }
.mobile-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 8px; }
.mobile-toggle span { width: 22px; height: 2px; background: var(--gray-700); border-radius: 2px; }

/* ===== HERO ===== */
.hero {
    position: relative; min-height: 90vh; display: flex; align-items: center;
    background: url('https://images.unsplash.com/photo-1582719471384-894fbb16f461?w=1600&q=80') center/cover no-repeat;
    margin-top: 72px;
}
.hero-overlay { position: absolute; inset: 0; background: linear-gradient(135deg, rgba(10,15,20,0.85) 0%, rgba(10,15,20,0.55) 100%); }
.hero-content { position: relative; z-index: 1; max-width: 640px; padding: 80px 0; }
.hero-badge {
    display: inline-block; padding: 8px 16px;
    background: rgba(13,148,136,0.2); border: 1px solid rgba(13,148,136,0.3);
    border-radius: 50px; color: var(--primary-light); font-size: 0.8rem; font-weight: 600; margin-bottom: 24px;
}
.hero h1 { font-size: clamp(2.5rem,5vw,3.5rem); font-weight: 800; line-height: 1.1; color: var(--white); margin-bottom: 20px; letter-spacing: -0.03em; }
.hero-desc { font-size: 1.1rem; color: rgba(255,255,255,0.8); line-height: 1.7; margin-bottom: 36px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }

/* ===== STATS ===== */
.stats { padding: 0; margin-top: -40px; position: relative; z-index: 10; }
.stats-grid { display: grid; grid-template-columns: repeat(4,1fr); background: var(--white); border-radius: var(--radius-lg); box-shadow: var(--shadow-lg); }
.stat-item { padding: 36px 24px; text-align: center; border-right: 1px solid var(--gray-200); }
.stat-item:last-child { border-right: none; }
.stat-item strong { display: block; font-size: 2rem; font-weight: 800; color: var(--primary); letter-spacing: -0.03em; margin-bottom: 4px; }
.stat-item span { font-size: 0.85rem; color: var(--gray-500); font-weight: 500; }

/* ===== SECTIONS ===== */
.section { padding: 100px 0; }
.section-header { text-align: center; max-width: 600px; margin: 0 auto 60px; }
.section-tag { display: inline-block; font-size: 0.8rem; font-weight: 700; color: var(--primary); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 12px; }
.section-header h2, .about-text h2, .impact-text h2, .contact-info h2 {
    font-size: clamp(1.8rem,3.5vw,2.5rem); font-weight: 800; color: var(--dark); line-height: 1.2; letter-spacing: -0.03em; margin-bottom: 16px;
}
.section-desc { font-size: 1.05rem; color: var(--gray-500); line-height: 1.7; }

/* ===== ABOUT ===== */
.about { background: var(--gray-50); }
.about-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 80px; align-items: center; }
.about-image img { border-radius: var(--radius-lg); width: 100%; height: 450px; object-fit: cover; }
.about-text p { color: var(--gray-600); margin-bottom: 24px; line-height: 1.7; }
.about-list { display: flex; flex-direction: column; gap: 16px; }
.about-list li { display: flex; align-items: center; gap: 12px; font-weight: 500; color: var(--gray-700); }
.about-list li svg { color: var(--primary); flex-shrink: 0; }

/* ===== RESEARCH ===== */
.research-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 32px; }
.research-card {
    background: var(--white); border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg); overflow: hidden; transition: var(--transition);
}
.research-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-4px); border-color: transparent; }
.research-img { height: 200px; overflow: hidden; }
.research-img img { width: 100%; height: 100%; object-fit: cover; transition: var(--transition); }
.research-card:hover .research-img img { transform: scale(1.05); }
.research-body { padding: 28px; }
.research-body h3 { font-size: 1.2rem; font-weight: 700; color: var(--dark); margin-bottom: 10px; }
.research-body > p { color: var(--gray-600); font-size: 0.95rem; margin-bottom: 16px; line-height: 1.6; }
.research-body ul { display: flex; flex-direction: column; gap: 8px; }
.research-body ul li { font-size: 0.88rem; color: var(--gray-600); padding-left: 16px; position: relative; }
.research-body ul li::before { content: ''; position: absolute; left: 0; top: 8px; width: 6px; height: 6px; border-radius: 50%; background: var(--primary); }

/* ===== SOLUTIONS ===== */
.solutions { background: var(--gray-50); }
.solutions-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 24px; }
.solution-item {
    padding: 32px 24px; background: var(--white); border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg); transition: var(--transition); text-align: center;
}
.solution-item:hover { border-color: var(--primary); box-shadow: var(--shadow); transform: translateY(-4px); }
.solution-icon {
    width: 56px; height: 56px; display: flex; align-items: center; justify-content: center;
    background: rgba(13,148,136,0.08); border-radius: 12px; margin: 0 auto 16px; color: var(--primary);
}
.solution-item h4 { font-size: 1rem; font-weight: 700; color: var(--dark); margin-bottom: 8px; }
.solution-item p { font-size: 0.88rem; color: var(--gray-500); line-height: 1.5; }

/* ===== IMPACT ===== */
.impact-layout { display: grid; grid-template-columns: 1fr 1.5fr; gap: 60px; align-items: center; }
.impact-text p { color: var(--gray-600); margin-top: 12px; line-height: 1.7; }
.impact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.impact-card {
    background: var(--dark); color: var(--white); padding: 36px 24px;
    border-radius: var(--radius-lg); text-align: center; transition: var(--transition);
}
.impact-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.impact-card strong { display: block; font-size: 2.2rem; font-weight: 800; color: var(--primary-light); margin-bottom: 8px; }
.impact-card p { color: var(--gray-400); font-size: 0.9rem; }

/* ===== CTA ===== */
.cta {
    position: relative; padding: 100px 0;
    background: url('https://images.unsplash.com/photo-1532187863486-abf9dbad1b69?w=1600&q=80') center/cover no-repeat;
}
.cta-overlay { position: absolute; inset: 0; background: rgba(13,148,136,0.9); }
.cta-content { position: relative; text-align: center; max-width: 600px; margin: 0 auto; }
.cta-content h2 { font-size: 2.2rem; font-weight: 800; color: var(--white); margin-bottom: 16px; letter-spacing: -0.02em; }
.cta-content p { font-size: 1.1rem; color: rgba(255,255,255,0.85); margin-bottom: 32px; }

/* ===== CONTACT ===== */
.contact-wrapper { display: grid; grid-template-columns: 1fr 1.2fr; gap: 80px; align-items: start; }
.contact-info > p { color: var(--gray-600); margin-bottom: 36px; line-height: 1.7; }
.contact-details { display: flex; flex-direction: column; gap: 24px; }
.contact-item { display: flex; align-items: flex-start; gap: 16px; }
.contact-item svg { color: var(--primary); margin-top: 2px; flex-shrink: 0; }
.contact-item strong { display: block; font-weight: 600; color: var(--dark); margin-bottom: 2px; font-size: 0.9rem; }
.contact-item p { color: var(--gray-600); font-size: 0.9rem; }
.contact-form { background: var(--gray-50); padding: 40px; border-radius: var(--radius-lg); border: 1px solid var(--gray-200); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 0.85rem; font-weight: 600; color: var(--gray-700); margin-bottom: 6px; }
.form-group input, .form-group textarea {
    width: 100%; padding: 12px 16px; border: 1px solid var(--gray-300); border-radius: var(--radius);
    font-size: 0.9rem; font-family: inherit; transition: var(--transition); background: var(--white); color: var(--dark);
}
.form-group input:focus, .form-group textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(13,148,136,0.08); }
.form-group textarea { resize: vertical; min-height: 120px; }

/* ===== FOOTER ===== */
.footer { background: var(--dark); color: var(--gray-400); padding: 80px 0 32px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 48px; margin-bottom: 60px; }
.footer-brand .logo { color: var(--white); margin-bottom: 16px; display: inline-block; }
.footer-brand p { color: var(--gray-500); line-height: 1.7; font-size: 0.9rem; }
.footer-links h4 { color: var(--white); font-weight: 600; font-size: 0.9rem; margin-bottom: 20px; }
.footer-links ul { display: flex; flex-direction: column; gap: 12px; }
.footer-links a { color: var(--gray-500); font-size: 0.88rem; }
.footer-links a:hover { color: var(--white); }
.footer-bottom { padding-top: 32px; border-top: 1px solid rgba(255,255,255,0.06); text-align: center; font-size: 0.85rem; color: var(--gray-500); }

/* ===== RESPONSIVE ===== */
@media (max-width: 1024px) {
    .about-layout, .impact-layout { grid-template-columns: 1fr; gap: 48px; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .contact-wrapper { grid-template-columns: 1fr; }
    .research-grid { grid-template-columns: 1fr; }
    .solutions-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
    .nav-links, .header .btn { display: none; }
    .mobile-toggle { display: flex; }
    .hero { min-height: 80vh; }
    .stats-grid { grid-template-columns: 1fr 1fr; }
    .stat-item { border-bottom: 1px solid var(--gray-200); }
    .section { padding: 64px 0; }
    .impact-grid { grid-template-columns: 1fr 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; }
    .contact-form { padding: 24px; }
}
@media (max-width: 480px) {
    .hero-actions { flex-direction: column; }
    .stats-grid { grid-template-columns: 1fr; }
    .stat-item { border-right: none !important; }
    .solutions-grid { grid-template-columns: 1fr; }
    .impact-grid { grid-template-columns: 1fr; }
}