:root {
  --tu-blue: #4ba3ff;
  --tu-green: #5ad29b;
  --tu-purple: #b18cff;
  --tu-dark-bg: #050816;
  --tu-dark-card: #0b1220;
  --tu-dark-border: #1f2937;
  --tu-dark-text: #e5e7eb;
  --tu-dark-muted: #9ca3af;
  --tu-light-bg: #f5f7fb;
  --tu-light-card: #ffffff;
  --tu-light-border: #dde2ee;
  --tu-light-text: #111827;
  --tu-light-muted: #4b5563;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  transition: background 0.25s ease, color 0.25s ease;
}

body[data-theme="dark"] {
  background: radial-gradient(circle at top, #111827 0, #020617 40%, #000 100%);
  color: var(--tu-dark-text);
}

body[data-theme="light"] {
  background: var(--tu-light-bg);
  color: var(--tu-light-text);
}

header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(16px);
}

body[data-theme="dark"] header {
  background: rgba(15, 23, 42, 0.9);
  border-bottom: 1px solid rgba(148, 163, 184, 0.4);
}

body[data-theme="light"] header {
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--tu-light-border);
}

.navbar {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0.6rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 10px;
  background: radial-gradient(circle at 10% 0, var(--tu-green), var(--tu-blue));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 700;
  font-size: 0.9rem;
}

.logo-text {
  font-weight: 600;
  letter-spacing: 0.03em;
}

body[data-theme="dark"] .logo-text { color: var(--tu-dark-text); }
body[data-theme="light"] .logo-text { color: var(--tu-light-text); }

nav {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.75rem;
}

nav a {
  text-decoration: none;
  font-size: 0.86rem;
}

body[data-theme="dark"] nav a {
  color: var(--tu-dark-muted);
}

body[data-theme="light"] nav a {
  color: var(--tu-light-muted);
}

nav a:hover {
  text-decoration: underline;
}

nav a.cta {
  padding: 0.35rem 0.9rem;
  border-radius: 999px;
  font-weight: 500;
  text-decoration: none;
}

body[data-theme="dark"] nav a.cta {
  background: linear-gradient(135deg, var(--tu-blue), var(--tu-green));
  color: #0b1120;
}

body[data-theme="light"] nav a.cta {
  background: var(--tu-blue);
  color: #ffffff;
}

.lang-switch {
  font-size: 0.76rem;
  opacity: 0.85;
}

.lang-switch a { margin-left: 0.35rem; }

.theme-toggle {
  border-radius: 999px;
  border: 1px solid rgba(148, 163, 184, 0.6);
  padding: 0.18rem 0.7rem;
  font-size: 0.78rem;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  cursor: pointer;
  background: transparent;
}

body[data-theme="dark"] .theme-toggle { color: var(--tu-dark-muted); }
body[data-theme="light"] .theme-toggle { color: var(--tu-light-muted); }

.theme-toggle span.icon { font-size: 0.9rem; }

main {
  max-width: 1080px;
  margin: 0 auto;
  padding: 1.5rem 1.5rem 2.5rem;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
  gap: 2rem;
  align-items: center;
  margin: 1.5rem 0 2.3rem;
}

.hero-copy h1 {
  font-size: clamp(2.1rem, 3vw, 2.8rem);
  margin-bottom: 0.8rem;
}

body[data-theme="dark"] .hero-copy h1 { color: #e5e7eb; }
body[data-theme="light"] .hero-copy h1 { color: #111827; }

.hero-copy p.lead {
  font-size: 1rem;
  line-height: 1.7;
  margin-bottom: 1rem;
}

body[data-theme="dark"] .hero-copy p.lead { color: var(--tu-dark-muted); }
body[data-theme="light"] .hero-copy p.lead { color: var(--tu-light-muted); }

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 1.2rem;
  border-radius: 999px;
  border: none;
  cursor: pointer;
  font-size: 0.9rem;
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--tu-blue), var(--tu-green));
  color: #020617;
}

.btn-ghost {
  background: transparent;
  border: 1px solid rgba(148, 163, 184, 0.8);
}

body[data-theme="dark"] .btn-ghost { color: var(--tu-dark-muted); }
body[data-theme="light"] .btn-ghost { color: var(--tu-light-muted); }

.hero-media {
  display: grid;
  gap: 0.85rem;
}

.hero-media img {
  width: 100%;
  border-radius: 18px;
  object-fit: cover;
  min-height: 160px;
  box-shadow: 0 16px 45px rgba(15, 23, 42, 0.7);
}

.hero-video {
  position: relative;
  overflow: hidden;
  border-radius: 18px;
  box-shadow: 0 16px 45px rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(148, 163, 184, 0.45);
}

.hero-video iframe {
  width: 100%;
  height: 220px;
  border: 0;
}

section {
  margin: 2.5rem 0;
}

section h2 {
  font-size: 1.35rem;
  margin-bottom: 0.75rem;
}

body[data-theme="dark"] section h2 { color: #e5e7eb; }
body[data-theme="light"] section h2 { color: #111827; }

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1.5rem;
}

.card {
  border-radius: 14px;
  padding: 1.15rem 1.2rem;
  font-size: 0.9rem;
}

body[data-theme="dark"] .card {
  background: radial-gradient(circle at top left, #111827, #020617);
  border: 1px solid var(--tu-dark-border);
  box-shadow: 0 12px 35px rgba(0, 0, 0, 0.7);
}

body[data-theme="light"] .card {
  background: var(--tu-light-card);
  border: 1px solid var(--tu-light-border);
  box-shadow: 0 8px 20px rgba(15, 23, 42, 0.06);
}

.card h3 {
  margin-top: 0;
  margin-bottom: 0.45rem;
  font-size: 1rem;
}

.card p {
  margin: 0 0 0.35rem 0;
  line-height: 1.6;
}

body[data-theme="dark"] .card p { color: var(--tu-dark-muted); }
body[data-theme="light"] .card p { color: var(--tu-light-muted); }

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0.2rem 0.55rem;
  border-radius: 999px;
  margin-bottom: 0.5rem;
}

body[data-theme="dark"] .badge {
  background: rgba(148, 163, 184, 0.18);
  color: #e5e7eb;
}

body[data-theme="light"] .badge {
  background: rgba(15, 23, 42, 0.06);
  color: #374151;
}

.badge.lab {
  background: rgba(177, 140, 255, 0.22);
  color: #ede9fe;
}

footer {
  border-top: 1px solid rgba(148, 163, 184, 0.5);
  padding: 1.25rem;
  font-size: 0.8rem;
  text-align: center;
}

body[data-theme="dark"] footer {
  background: #020617;
  color: var(--tu-dark-muted);
}

body[data-theme="light"] footer {
  background: #ffffff;
  color: var(--tu-light-muted);
}

footer a {
  text-decoration: none;
}

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

@media (max-width: 768px) {
  .hero {
    grid-template-columns: minmax(0, 1fr);
  }
  .hero-video iframe {
    height: 200px;
  }
}