:root {
  --primary: #1565c0;
  --secondary: #1976d2;
  --accent: #42a5f5;
  --bg: #ffffff;
  --bg-soft: #ffffff;
  --surface: #ffffff;
  --surface-alt: #ffffff;
  --text: #1a1a1a;
  --muted: #4a4a4a;
  --border: rgba(21, 101, 192, 0.15);
  --shadow-soft: 0 8px 22px rgba(20, 70, 150, 0.08);
  --shadow-strong: 0 14px 30px rgba(20, 70, 150, 0.14);
  --radius: 18px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Inter", Arial, sans-serif;
  background: #ffffff;
  color: var(--text);
  line-height: 1.6;
}

img {
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: min(1100px, 92%);
  margin: 0 auto;
}

.section {
  padding: 64px 0;
}

.section-alt {
  background: #ffffff;
}

.section-title {
  margin-bottom: 28px;
}

.section-title h2 {
  font-size: clamp(1.8rem, 3vw, 2.3rem);
  margin-bottom: 10px;
}

.section-title p {
  color: var(--muted);
  max-width: 700px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  background: #1565c0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
}

.nav-bar {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.15rem;
  letter-spacing: 0.4px;
  color: #ffffff;
}

.brand-logo {
  width: 42px;
  height: 42px;
  object-fit: contain;
  border-radius: 50%;
  background: none;
  padding: 2px;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 24px;
}

.nav-links a {
  color: #eaf3ff;
  font-weight: 500;
  transition: color 0.35s ease;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: #ffffff;
}

.nav-toggle {
  display: none;
  border: 0;
  background: transparent;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  margin: 5px 0;
  background: #ffffff;
  border-radius: 2px;
}

.hero {
  padding: 56px 0 48px;
  background: #ffffff;
  color: var(--text);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 24px;
  align-items: center;
}

.eyebrow {
  color: var(--primary);
  text-transform: uppercase;
  font-weight: 700;
  letter-spacing: 0.08em;
  font-size: 0.78rem;
  margin-bottom: 10px;
}

.hero h1 {
  font-size: clamp(2rem, 5.4vw, 3.5rem);
  line-height: 1.1;
  margin-bottom: 16px;
}

.hero-text {
  color: var(--muted);
  max-width: 620px;
  margin-bottom: 24px;
}

.btn {
  display: inline-block;
  background: var(--primary);
  color: #ffffff;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 700;
  border: none;
  cursor: pointer;
  transition: transform 0.35s ease, box-shadow 0.35s ease, background 0.35s ease;
}

.btn:hover,
.btn:focus-visible {
  transform: translateY(-3px) scale(1.02);
  background: var(--secondary);
  box-shadow: 0 12px 24px rgba(10, 80, 25, 0.2);
}

.hero-cards,
.research-grid,
.modules-grid,
.docs-grid,
.team-grid {
  display: grid;
  gap: 16px;
}

.hero-cards {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.research-grid,
.docs-grid,
.team-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.modules-grid {
  margin-top: 18px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

/* Compact research section cards (avoid tall empty whitespace) */
#research .research-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  align-items: start;
  gap: 14px;
}

#research .card {
  padding: 16px;
  height: auto;
}

#research .card h3 {
  margin-bottom: 8px;
}

#research .card p,
#research .card li {
  line-height: 1.45;
}

#research .card li {
  margin-bottom: 6px;
}

#research .card li:last-child {
  margin-bottom: 0;
}

.card,
.module-card {
  background: linear-gradient(180deg, var(--surface) 0%, var(--surface-alt) 100%);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
  padding: 22px;
  transition: transform 0.35s ease, border-color 0.35s ease, box-shadow 0.35s ease, background 0.35s ease;
}

.module-card:hover,
.card:hover {
  transform: translateY(-6px) scale(1.01);
  border-color: rgba(21, 101, 192, 0.35);
  box-shadow: var(--shadow-strong);
  background: #ffffff;
}

.card h3,
.module-card h3 {
  margin-bottom: 10px;
  font-size: 1.06rem;
}

.card p,
.module-card p,
.card li {
  color: var(--muted);
}

.card ul {
  padding-left: 18px;
}

.icon {
  font-size: 1.6rem;
  margin-bottom: 10px;
}

.architecture {
  margin-bottom: 18px;
}

.architecture-layout {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 18px;
  align-items: center;
}

.architecture-image {
  width: 100%;
  height: 220px;
  object-fit: cover;
  border-radius: 14px;
  border: 1px solid rgba(21, 101, 192, 0.18);
}

.role {
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 8px;
}

.docs-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.docs-card {
  display: flex;
  flex-direction: column;
}

.docs-head {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}

.docs-badge {
  display: inline-grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: linear-gradient(130deg, #e3f2fd 0%, #bbdefb 100%);
  font-size: 1rem;
}

.docs-note {
  margin-bottom: 14px;
}

.doc-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.doc-link-btn {
  display: inline-block;
  padding: 9px 13px;
  border-radius: 999px;
  background: #f3f8ff;
  color: var(--primary);
  border: 1px solid rgba(21, 101, 192, 0.2);
  font-size: 0.92rem;
  font-weight: 600;
  transition: transform 0.32s ease, box-shadow 0.32s ease, background 0.32s ease;
}

.doc-link-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 18px rgba(20, 70, 150, 0.15);
  background: #e8f1ff;
}

.team-carousel {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
}

.carousel-track-wrapper {
  overflow: hidden;
  width: 100%;
}

.carousel-track {
  display: flex;
  transition: transform 0.45s ease;
  touch-action: pan-y;
}

.team-card {
  min-width: calc(100% / 3);
  margin-right: 12px;
  text-align: center;
}

.team-photo {
  width: 110px;
  height: 110px;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid #e3f2fd;
  margin: 0 auto 12px;
}

/* Modern About Us team layout (grid fallback) */
#about .team-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

/* About Us carousel */
.about-team-carousel {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  max-width: 100%;
}

.about-carousel-viewport {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  border-radius: var(--radius);
}

.about-carousel-track {
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  transition: transform 0.45s ease;
  will-change: transform;
}

.about-carousel-page {
  display: flex;
  flex: 0 0 100%;
  box-sizing: border-box;
  gap: 16px;
  justify-content: center;
  align-items: stretch;
  padding: 0 4px;
}

.about-carousel-page .team-profile-card {
  flex: 1 1 0;
  min-width: 0;
  max-width: 340px;
}

.about-carousel-btn {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1px solid rgba(21, 101, 192, 0.2);
  background: #ffffff;
  color: var(--primary);
  font-size: 1rem;
  cursor: pointer;
  box-shadow: var(--shadow-soft);
  transition: transform 0.25s ease, background 0.25s ease, box-shadow 0.25s ease;
}

.about-carousel-btn:hover {
  transform: scale(1.06);
  background: #eaf3ff;
  box-shadow: 0 8px 18px rgba(20, 70, 150, 0.12);
}

.team-profile-card {
  text-align: center;
  padding: 18px 18px 16px;
  min-height: 0;
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.team-profile-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 14px 24px rgba(20, 70, 150, 0.14);
}

.team-profile-card h3 {
  margin-bottom: 6px;
}

.member-desc {
  font-size: 0.92rem;
  line-height: 1.5;
  margin-bottom: 10px;
}

.module-tag {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid rgba(21, 101, 192, 0.25);
  background: #eef5ff;
  color: var(--primary);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.carousel-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1px solid rgba(21, 101, 192, 0.2);
  background: #ffffff;
  color: var(--primary);
  font-size: 1.1rem;
  cursor: pointer;
  box-shadow: var(--shadow-soft);
  transition: transform 0.3s ease, background 0.3s ease;
}

.carousel-btn:hover {
  transform: scale(1.05);
  background: #eaf3ff;
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  max-width: 860px;
  margin: 0 auto;
}

.contact-info p + p {
  margin-top: 10px;
}

.contact-form {
  display: flex;
  flex-direction: column;
}

.contact-form label {
  margin-top: 10px;
  margin-bottom: 6px;
  font-weight: 600;
}

.contact-form input,
.contact-form textarea {
  background: #ffffff;
  border: 1px solid rgba(21, 101, 192, 0.18);
  border-radius: 10px;
  color: var(--text);
  padding: 12px;
  font: inherit;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(66, 165, 245, 0.24);
}

.contact-form .btn {
  margin-top: 18px;
  align-self: flex-start;
}

.form-feedback {
  margin-top: 12px;
  font-weight: 600;
  min-height: 24px;
  color: var(--muted);
}

.form-feedback.success {
  color: #1b8f3a;
}

.form-feedback.error {
  color: #c62828;
}

.site-footer {
  border-top: 1px solid rgba(21, 101, 192, 0.12);
  background: #ffffff;
  color: var(--text);
}

.footer-content {
  min-height: 100px;
  display: grid;
  grid-template-columns: 1.3fr 1fr 1fr;
  gap: 18px;
  align-items: center;
  padding: 14px 0;
}

.footer-brand {
  font-weight: 700;
}

.footer-note {
  opacity: 0.8;
  font-size: 0.92rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-links a {
  opacity: 0.95;
}

.footer-links a:hover {
  text-decoration: underline;
}

.footer-contact p {
  font-size: 0.92rem;
}

/* Fade-in animation for section content */
.fade-in {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.fade-in.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 980px) {
  .hero-grid,
  .contact-grid,
  .architecture-layout {
    grid-template-columns: 1fr;
  }

  .research-grid,
  .docs-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  #about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .about-carousel-page .team-profile-card {
    max-width: none;
  }

  .team-card {
    min-width: calc(100% / 2);
  }

  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }

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

@media (max-width: 760px) {
  .nav-toggle {
    display: block;
  }

  .nav-links {
    position: absolute;
    right: 4%;
    top: 72px;
    width: min(270px, 90%);
    background: rgba(21, 101, 192, 0.98);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 14px;
    flex-direction: column;
    gap: 10px;
    transform: scale(0.98);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s ease;
  }

  .nav-links.open {
    opacity: 1;
    pointer-events: auto;
    transform: scale(1);
  }

  .hero-cards,
  .research-grid,
  .modules-grid,
  .docs-grid {
    grid-template-columns: 1fr;
  }

  #about .team-grid {
    grid-template-columns: 1fr;
  }

  .about-team-carousel {
    flex-wrap: wrap;
    gap: 10px;
  }

  .about-carousel-btn {
    width: 36px;
    height: 36px;
    font-size: 0.95rem;
  }

  .about-carousel-page {
    flex-direction: column;
    align-items: center;
  }

  .about-carousel-page .team-profile-card {
    max-width: 420px;
    width: 100%;
  }

  #research .research-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 52px 0;
  }

  .hero {
    padding: 44px 0 40px;
  }

  .team-carousel {
    gap: 6px;
  }

  .team-card {
    min-width: 100%;
    margin-right: 8px;
  }

  .carousel-btn {
    width: 34px;
    height: 34px;
  }
}