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

body {
  background: #0a0a0f;
  color: #e8e8f0;
  font-family: 'Segoe UI', system-ui, sans-serif;
  line-height: 1.6;
}

a { color: #a78bfa; text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---- Nav ---- */
nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem 2rem;
  border-bottom: 1px solid #1e1e2e;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
}
.logo:hover { text-decoration: none; }
.logo-mark { flex-shrink: 0; }
.logo-text { font-size: 1.15rem; font-weight: 700; letter-spacing: 0.05em; color: #fff; }

nav ul { list-style: none; display: flex; gap: 2rem; }
nav ul a { color: #a0a0b8; font-size: 0.95rem; }
nav ul a:hover { color: #fff; text-decoration: none; }

/* ---- Hero ---- */
.hero {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6rem 2rem;
  max-width: 1100px;
  margin: 0 auto;
  gap: 3rem;
}

.hero-content { max-width: 540px; }

.formula-badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: #a78bfa;
  border: 1px solid #a78bfa44;
  background: #a78bfa10;
  padding: 0.3rem 0.9rem;
  border-radius: 999px;
  margin-bottom: 1.5rem;
}

.formula-display {
  font-family: 'Georgia', 'Times New Roman', serif;
  font-size: 5rem;
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 1.25rem;
  letter-spacing: -0.02em;
}
.formula-op { color: #505070; margin: 0 0.05em; }
.formula-exp { font-size: 0.5em; vertical-align: super; }

.vowel-a { color: #f472b6; background: linear-gradient(135deg, #f472b6, #a78bfa); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.vowel-e { color: #a78bfa; background: linear-gradient(135deg, #a78bfa, #7c3aed); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.vowel-i { color: #7c3aed; background: linear-gradient(135deg, #7c3aed, #6366f1); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.vowel-o { color: #6366f1; background: linear-gradient(135deg, #6366f1, #3b82f6); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.vowel-u { color: #3b82f6; background: linear-gradient(135deg, #3b82f6, #60a5fa); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }

.tagline {
  font-size: 1.35rem;
  font-weight: 600;
  color: #c8c8d8;
  margin-bottom: 0.75rem;
}
.accent { color: #a78bfa; background: linear-gradient(90deg, #a78bfa, #60a5fa); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }

.hero-sub { font-size: 1.05rem; color: #8080a0; margin-bottom: 2rem; max-width: 480px; }

.hero-actions { display: flex; gap: 1rem; flex-wrap: wrap; }

.btn {
  display: inline-block;
  background: linear-gradient(135deg, #7c3aed, #3b82f6);
  color: #fff;
  padding: 0.75rem 1.75rem;
  border-radius: 8px;
  font-weight: 600;
  transition: opacity 0.2s;
}
.btn:hover { opacity: 0.85; text-decoration: none; }
.btn-outline {
  background: transparent;
  border: 1px solid #3b3b5c;
  color: #a0a0b8;
}
.btn-outline:hover { border-color: #a78bfa; color: #e8e8f0; opacity: 1; }

/* ---- Hero visual ---- */
.hero-visual {
  flex-shrink: 0;
  position: relative;
  width: 320px;
  height: 320px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.orb {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background: radial-gradient(circle at 40% 40%, #7c3aed55, #3b82f633, transparent 70%);
  filter: blur(50px);
}
.hero-logo-svg {
  position: relative;
  width: 300px;
  height: 300px;
  animation: float 6s ease-in-out infinite;
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

/* ---- Sections ---- */
.section {
  max-width: 1100px;
  margin: 0 auto;
  padding: 5rem 2rem;
}
.section.alt { background: #0e0e18; border-radius: 16px; }
.section h2 { font-size: 2rem; font-weight: 700; margin-bottom: 1.25rem; }
.section p { color: #a0a0b8; max-width: 640px; }

.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1.5rem; margin-top: 2rem; }
.card { background: #13131f; border: 1px solid #1e1e30; border-radius: 12px; padding: 1.75rem; transition: border-color 0.25s, transform 0.25s; }
.card:hover { border-color: #a78bfa44; transform: translateY(-4px); }
.card h3 { font-size: 1.1rem; margin-bottom: 0.5rem; color: #e8e8f0; }
.card p { color: #7070a0; font-size: 0.95rem; }

footer {
  text-align: center;
  padding: 2rem;
  color: #404060;
  font-size: 0.85rem;
  border-top: 1px solid #1e1e2e;
  margin-top: 4rem;
}

/* ---- Responsive ---- */
@media (max-width: 768px) {
  .hero { flex-direction: column; padding: 3rem 1.5rem; text-align: center; }
  .hero-content { max-width: 100%; }
  .formula-display { font-size: 3.2rem; }
  .hero-actions { justify-content: center; }
  .hero-visual { width: 220px; height: 220px; }
  .hero-logo-svg { width: 200px; height: 200px; }
  .hero-sub { margin-left: auto; margin-right: auto; }
}