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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: #1e293b;
  background-color: #ffffff;
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a {
  color: #2563eb;
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: #1d4ed8;
}

img {
  max-width: 100%;
  height: auto;
}

/* ===== Navigation ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  padding: 1rem 0;
  transition: all 0.3s ease;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 1px 20px rgba(0, 0, 0, 0.06);
  padding: 0.6rem 0;
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  font-size: 1.1rem;
  font-weight: 700;
  color: #1e293b;
  letter-spacing: -0.3px;
}

.nav-brand:hover {
  color: #2563eb;
}

.nav-menu {
  list-style: none;
  display: flex;
  gap: 0.2rem;
}

.nav-menu a {
  color: #334155;
  font-size: 0.95rem;
  font-weight: 600;
  padding: 0.5rem 0.9rem;
  border-radius: 6px;
  transition: all 0.2s ease;
}

.nav-menu a:hover {
  color: #2563eb;
  background: rgba(37, 99, 235, 0.06);
}

/* Hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #1e293b;
  border-radius: 2px;
  transition: all 0.3s ease;
}

.nav-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ===== Hero Section ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 120px 2rem 80px;
}

.hero-container {
  max-width: 1000px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 4rem;
}

.hero-text {
  flex: 1;
}

.hero-text .greeting {
  font-size: 1rem;
  font-weight: 500;
  color: #2563eb;
  margin-bottom: 0.75rem;
  letter-spacing: 0.5px;
}

.hero-text h1 {
  font-size: 3.2rem;
  font-weight: 700;
  color: #0f172a;
  line-height: 1.12;
  margin-bottom: 0.3rem;
  letter-spacing: -1.5px;
}

.hero-text .tagline {
  font-size: 1.35rem;
  color: #64748b;
  font-weight: 400;
  margin-bottom: 1.75rem;
  line-height: 1.5;
}

.hero-links {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.65rem 1.3rem;
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.2s ease;
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: #2563eb;
  color: #fff;
}

.btn-primary:hover {
  background: #1d4ed8;
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
}

.btn-outline {
  border: 1.5px solid #cbd5e1;
  color: #475569;
  background: transparent;
}

.btn-outline:hover {
  border-color: #2563eb;
  color: #2563eb;
  transform: translateY(-1px);
}

.hero-image {
  flex-shrink: 0;
}

.hero-image img {
  width: 260px;
  height: 260px;
  border-radius: 50%;
  object-fit: cover;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
}

/* ===== Sections (shared) ===== */
section {
  padding: 80px 2rem;
}

.section-container {
  max-width: 1000px;
  margin: 0 auto;
}

.section-title {
  font-size: 1.6rem;
  font-weight: 700;
  color: #0f172a;
  margin-bottom: 2.5rem;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 36px;
  height: 3px;
  background: #2563eb;
  border-radius: 2px;
}

.section-title[style*="text-align: center"]::after {
  left: 50%;
  transform: translateX(-50%);
}

.section-alt {
  background: #f8fafc;
}

/* ===== Capability Cards ===== */
.capabilities-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.capability-card {
  background: #fff;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  padding: 1.75rem 1.5rem;
  transition: all 0.25s ease;
  text-align: center;
}

.capability-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.06);
  border-color: #bfdbfe;
}

.capability-icon {
  font-size: 2rem;
  margin-bottom: 0.75rem;
  display: block;
}

.capability-card h3 {
  font-size: 1rem;
  font-weight: 600;
  color: #0f172a;
  margin-bottom: 0.5rem;
}

.capability-card p {
  font-size: 0.85rem;
  color: #64748b;
  line-height: 1.55;
}

/* ===== Highlights ===== */
.highlights-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  text-align: center;
}

.highlight-item {
  padding: 1.5rem;
}

.highlight-number {
  font-size: 2.5rem;
  font-weight: 700;
  color: #2563eb;
  line-height: 1;
  margin-bottom: 0.5rem;
}

.highlight-label {
  font-size: 0.95rem;
  color: #475569;
  line-height: 1.5;
}

/* ===== Publications (landing page) ===== */
.pub-list {
  list-style: none;
  padding: 0;
}

.pub-list li {
  padding: 1rem 0;
  border-bottom: 1px solid #e2e8f0;
  display: flex;
  gap: 1rem;
  align-items: baseline;
}

.pub-list li:last-child {
  border-bottom: none;
}

.pub-type {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: #2563eb;
  background: #eff6ff;
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
  white-space: nowrap;
  flex-shrink: 0;
}

.pub-text {
  font-size: 0.925rem;
  color: #334155;
  line-height: 1.6;
}

/* ===== Certifications ===== */
.cert-list {
  list-style: none;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.cert-list li {
  padding: 0.4rem 0.9rem;
  background: #f1f5f9;
  color: #475569;
  font-size: 0.825rem;
  font-weight: 500;
  border-radius: 6px;
}

/* ===== Contact Section ===== */
.contact-content {
  text-align: center;
  max-width: 550px;
  margin: 0 auto;
}

.contact-content p {
  font-size: 1.05rem;
  color: #64748b;
  margin-bottom: 2rem;
  line-height: 1.7;
}

.contact-links {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.contact-links a {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.65rem 1.4rem;
  border: 1.5px solid #e2e8f0;
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 500;
  color: #475569;
  transition: all 0.2s ease;
}

.contact-links a:hover {
  border-color: #2563eb;
  color: #2563eb;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.1);
}

/* ===== Footer ===== */
.footer {
  padding: 2.5rem 2rem;
  border-top: 1px solid #f1f5f9;
}

.footer-container {
  max-width: 1000px;
  margin: 0 auto;
  text-align: center;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 0.75rem;
}

.footer-links a {
  font-size: 0.85rem;
  color: #94a3b8;
  font-weight: 500;
}

.footer-links a:hover {
  color: #2563eb;
}

.footer-copy {
  font-size: 0.8rem;
  color: #cbd5e1;
}

/* ===== Project Case Studies ===== */
.case-study {
  margin-bottom: 3rem;
  padding-bottom: 3rem;
  border-bottom: 1px solid #e2e8f0;
}

.case-study:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.case-study h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: #0f172a;
  margin-bottom: 1.25rem;
}

.case-study h3 a {
  color: #0f172a;
}

.case-study h3 a:hover {
  color: #2563eb;
}

.case-study-meta {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 1.25rem;
}

.case-study-meta span {
  font-size: 0.75rem;
  font-weight: 500;
  padding: 0.2rem 0.65rem;
  background: #eff6ff;
  color: #2563eb;
  border-radius: 4px;
}

.case-study-section {
  margin-bottom: 1rem;
}

.case-study-section h4 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #2563eb;
  margin-bottom: 0.5rem;
  margin-top: 1.5rem;
}

.case-study-section p {
  font-size: 0.95rem;
  color: #475569;
  line-height: 1.7;
}

/* ===== About Page ===== */
.about-content {
  max-width: 900px;
  margin: 0 auto;
}

.about-content p {
  font-size: 1.05rem;
  color: #334155;
  line-height: 1.85;
  margin-bottom: 1.5rem;
}

.about-content p:last-child {
  margin-bottom: 0;
}

.about-content strong {
  color: #0f172a;
  font-weight: 600;
}

.about-content a {
  border-bottom: 1px solid #bfdbfe;
}

.about-content a:hover {
  border-bottom-color: #2563eb;
}

/* ===== Page Header (for sub-pages) ===== */
.page-hero {
  padding: 140px 2rem 60px;
  background: #f8fafc;
}

.page-hero h1 {
  font-size: 2.5rem;
  font-weight: 700;
  color: #0f172a;
  letter-spacing: -1px;
  margin-bottom: 0.5rem;
}

.page-hero .subtitle {
  font-size: 1.1rem;
  color: #64748b;
}

/* ===== Scroll Reveal ===== */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .capabilities-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .highlights-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(12px);
    flex-direction: column;
    padding: 1rem 2rem 1.5rem;
    gap: 0;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
  }

  .nav-menu.active {
    display: flex;
  }

  .nav-menu a {
    padding: 0.7rem 0;
    font-size: 1rem;
  }

  .hero {
    padding: 100px 1.5rem 60px;
  }

  .hero-container {
    flex-direction: column-reverse;
    text-align: center;
    gap: 2rem;
  }

  .hero-text h1 {
    font-size: 2.2rem;
  }

  .hero-text .tagline {
    font-size: 1.1rem;
  }

  .hero-links {
    justify-content: center;
  }

  .hero-image img {
    width: 180px;
    height: 180px;
  }

  section {
    padding: 60px 1.5rem;
  }

  .highlights-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .highlight-number {
    font-size: 2rem;
  }

  .pub-list li {
    flex-direction: column;
    gap: 0.4rem;
  }

  .page-hero {
    padding: 110px 1.5rem 40px;
  }

  .page-hero h1 {
    font-size: 1.8rem;
  }
}

@media (max-width: 480px) {
  .hero-text h1 {
    font-size: 1.8rem;
  }

  .capabilities-grid {
    grid-template-columns: 1fr;
  }

  .contact-links {
    flex-direction: column;
    align-items: center;
  }
}