:root {
  --bg: #0a0a0f;
  --bg-surface: #111118;
  --bg-card: #16161f;
  --fg: #e8e8ed;
  --fg-muted: #8888a0;
  --accent: #00e5c3;
  --accent-dim: rgba(0, 229, 195, 0.12);
  --accent-glow: rgba(0, 229, 195, 0.25);
  --border: rgba(255, 255, 255, 0.06);
  --heading: Space Grotesk, sans-serif;
  --body: DM Sans, sans-serif;
  --max-w: 1120px;
}

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

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-family: var(--heading);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

/* ─── HERO ─── */
.hero {
  min-height: 92vh;
  display: flex;
  align-items: center;
  padding: 80px 40px 60px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -40%;
  right: -20%;
  width: 80vw;
  height: 80vw;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 65%);
  opacity: 0.3;
  pointer-events: none;
}

.hero-grid {
  max-width: var(--max-w);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 60px;
  align-items: center;
  width: 100%;
}

.hero-tag {
  display: inline-block;
  font-family: var(--heading);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-dim);
  padding: 6px 16px;
  border-radius: 4px;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: clamp(2.6rem, 5.5vw, 4.2rem);
  color: #fff;
  margin-bottom: 28px;
}

.hero h1 .accent {
  color: var(--accent);
}

.lede {
  font-size: 1.15rem;
  color: var(--fg-muted);
  max-width: 520px;
  line-height: 1.7;
}

/* Qubit Visual */
.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.qubit-ring {
  position: relative;
  width: 320px;
  height: 320px;
}

.qubit-core {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 16px;
  height: 16px;
  background: var(--accent);
  border-radius: 50%;
  box-shadow: 0 0 40px var(--accent-glow), 0 0 80px var(--accent-glow);
}

.orbit {
  position: absolute;
  top: 50%;
  left: 50%;
  border: 1px solid var(--border);
  border-radius: 50%;
}

.orbit-1 {
  width: 140px;
  height: 140px;
  transform: translate(-50%, -50%) rotate(30deg);
  border-color: rgba(0, 229, 195, 0.15);
  animation: spin 12s linear infinite;
}

.orbit-2 {
  width: 220px;
  height: 220px;
  transform: translate(-50%, -50%) rotate(-15deg);
  border-color: rgba(0, 229, 195, 0.1);
  animation: spin 18s linear infinite reverse;
}

.orbit-3 {
  width: 300px;
  height: 300px;
  transform: translate(-50%, -50%) rotate(60deg);
  border-color: rgba(0, 229, 195, 0.06);
  animation: spin 25s linear infinite;
}

.particle {
  position: absolute;
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  box-shadow: 0 0 12px var(--accent-glow);
}

.p1 { top: 15%; left: 55%; animation: pulse 2.5s ease-in-out infinite; }
.p2 { top: 50%; right: 5%; animation: pulse 3s ease-in-out infinite 0.5s; }
.p3 { bottom: 20%; left: 30%; animation: pulse 2s ease-in-out infinite 1s; }
.p4 { top: 35%; left: 10%; animation: pulse 2.8s ease-in-out infinite 1.5s; }

@keyframes spin { to { transform: translate(-50%, -50%) rotate(390deg); } }
@keyframes pulse { 0%, 100% { opacity: 0.4; transform: scale(1); } 50% { opacity: 1; transform: scale(1.6); } }

/* ─── PROBLEM ─── */
.problem {
  padding: 100px 40px;
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.problem-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}

.stat-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  margin-bottom: 48px;
}

.stat {
  text-align: center;
}

.stat-number {
  display: block;
  font-family: var(--heading);
  font-size: clamp(2.4rem, 5vw, 3.4rem);
  font-weight: 700;
  color: var(--accent);
  line-height: 1.1;
  margin-bottom: 8px;
}

.stat-label {
  font-size: 0.9rem;
  color: var(--fg-muted);
  line-height: 1.5;
}

.problem-statement {
  font-size: 1.2rem;
  color: var(--fg);
  text-align: center;
  max-width: 760px;
  margin: 0 auto;
  line-height: 1.75;
}

/* ─── DOMAINS ─── */
.domains {
  padding: 120px 40px;
  max-width: var(--max-w);
  margin: 0 auto;
}

.domains h2 {
  font-size: clamp(2rem, 4vw, 2.8rem);
  color: #fff;
  margin-bottom: 64px;
}

.domain-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.domain-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 36px 28px;
  transition: border-color 0.3s ease, transform 0.3s ease;
}

.domain-card:hover {
  border-color: rgba(0, 229, 195, 0.2);
  transform: translateY(-4px);
}

.domain-icon {
  font-size: 1.6rem;
  margin-bottom: 20px;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-dim);
  border-radius: 10px;
  color: var(--accent);
}

.domain-card h3 {
  font-size: 1.25rem;
  color: #fff;
  margin-bottom: 12px;
}

.domain-card p {
  font-size: 0.95rem;
  color: var(--fg-muted);
  line-height: 1.65;
  margin-bottom: 20px;
}

.domain-tech {
  font-family: var(--heading);
  font-size: 0.75rem;
  color: var(--accent);
  letter-spacing: 0.06em;
  opacity: 0.7;
}

/* ─── HOW ─── */
.how {
  padding: 100px 40px;
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.how-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}

.how h2 {
  font-size: clamp(1.8rem, 3.5vw, 2.4rem);
  color: #fff;
  margin-bottom: 16px;
}

.how-desc {
  font-size: 1.05rem;
  color: var(--fg-muted);
  max-width: 640px;
  margin-bottom: 56px;
  line-height: 1.7;
}

.how-steps {
  display: flex;
  flex-direction: column;
  gap: 36px;
}

.step {
  display: flex;
  gap: 28px;
  align-items: flex-start;
}

.step-num {
  font-family: var(--heading);
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--accent);
  opacity: 0.35;
  line-height: 1;
  min-width: 60px;
}

.step-text h4 {
  font-size: 1.1rem;
  color: #fff;
  margin-bottom: 6px;
}

.step-text p {
  font-size: 0.95rem;
  color: var(--fg-muted);
  line-height: 1.6;
}

/* ─── CLOSING ─── */
.closing {
  padding: 120px 40px;
  text-align: center;
}

.closing-inner {
  max-width: 720px;
  margin: 0 auto;
}

.closing h2 {
  font-size: clamp(2rem, 4vw, 2.8rem);
  color: #fff;
  margin-bottom: 24px;
}

.closing p {
  font-size: 1.1rem;
  color: var(--fg-muted);
  line-height: 1.75;
}

/* ─── FOOTER ─── */
.site-footer {
  padding: 48px 40px;
  border-top: 1px solid var(--border);
  text-align: center;
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}

.footer-brand {
  font-family: var(--heading);
  font-size: 1.2rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: 6px;
}

.footer-tagline {
  font-size: 0.9rem;
  color: var(--fg-muted);
  margin-bottom: 20px;
}

.footer-bottom {
  font-size: 0.8rem;
  color: var(--fg-muted);
  opacity: 0.6;
}

.footer-sep {
  margin: 0 8px;
}

/* ─── RESPONSIVE ─── */
@media (max-width: 768px) {
  .hero {
    min-height: auto;
    padding: 60px 24px;
  }
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .hero-visual {
    order: -1;
  }
  .qubit-ring {
    width: 220px;
    height: 220px;
  }
  .orbit-1 { width: 100px; height: 100px; }
  .orbit-2 { width: 160px; height: 160px; }
  .orbit-3 { width: 210px; height: 210px; }
  .stat-row {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .domain-grid {
    grid-template-columns: 1fr;
  }
  .problem, .how, .domains, .closing {
    padding: 72px 24px;
  }
  .step {
    flex-direction: column;
    gap: 8px;
  }
  .step-num {
    font-size: 1.6rem;
    min-width: auto;
  }
}
/* ─── NAV ─── */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 16px 40px;
  background: rgba(10, 10, 15, 0.8);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-family: var(--heading);
  font-size: 1.15rem;
  font-weight: 700;
  color: #fff;
  text-decoration: none;
  letter-spacing: -0.02em;
}

.btn-demo {
  font-family: var(--heading);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--accent);
  text-decoration: none;
  border: 1px solid rgba(0, 229, 195, 0.3);
  padding: 8px 20px;
  border-radius: 6px;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.btn-demo:hover {
  background: var(--accent-dim);
  border-color: rgba(0, 229, 195, 0.6);
}

/* ─── CTA ─── */
.hero-cta {
  margin-top: 36px;
}

.cta-primary {
  display: inline-block;
  font-family: var(--heading);
  font-size: 0.95rem;
  font-weight: 600;
  color: #0a0a0f;
  background: var(--accent);
  padding: 14px 32px;
  border-radius: 6px;
  text-decoration: none;
  letter-spacing: 0.01em;
  transition: opacity 0.2s ease, transform 0.2s ease;
  box-shadow: 0 0 32px var(--accent-glow);
}

.cta-primary:hover {
  opacity: 0.88;
  transform: translateY(-2px);
}