:root {
  --primary-dark: #022c22;
  --forest-green: #064e3b;
  --emerald: #10b981;
  --emerald-light: #d1fae5;
  --cyan: #06b6d4;
  --cyan-light: #cffafe;
  --slate-900: #0f172a;
  --slate-700: #334155;
  --slate-100: #f1f5f9;
  --bg-dark: #022c22;
  --bg-light: #f8fafc;
  --font-sans: 'Space Grotesk', -apple-system, sans-serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
  --shadow-glow: 0 0 25px rgba(16, 185, 129, 0.25);
  --shadow-lg: 0 10px 25px -5px rgba(0,0,0,0.15);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: var(--font-body); color: var(--slate-900); background: var(--bg-light); line-height: 1.6; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* Futuristic Header */
.header {
  background: rgba(2, 44, 34, 0.95);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid rgba(16, 185, 129, 0.2);
}
.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 0;
}
.brand-stem {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: #ffffff;
}
.stem-logo-badge {
  width: 46px;
  height: 46px;
  background: linear-gradient(135deg, var(--emerald), var(--cyan));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #022c22;
  font-weight: 800;
  font-size: 20px;
}
.brand-text h1 {
  font-family: var(--font-sans);
  font-size: 1.35rem;
  letter-spacing: -0.5px;
  color: #ffffff;
}
.brand-text span {
  font-size: 0.76rem;
  color: var(--cyan);
  text-transform: uppercase;
  letter-spacing: 1.5px;
  font-weight: 600;
}
.nav-links {
  display: flex;
  list-style: none;
  align-items: center;
  gap: 24px;
}
.nav-links a {
  text-decoration: none;
  color: #cbd5e1;
  font-size: 0.92rem;
  font-weight: 500;
  transition: all 0.2s;
}
.nav-links a:hover {
  color: var(--emerald);
}
.btn-emerald {
  background: linear-gradient(135deg, var(--emerald), #059669);
  color: #ffffff !important;
  padding: 8px 18px;
  border-radius: 6px;
  font-weight: 600 !important;
  box-shadow: var(--shadow-glow);
  border: none;
  cursor: pointer;
  transition: all 0.2s;
}
.btn-emerald:hover {
  transform: translateY(-1px);
  filter: brightness(1.1);
}

/* Hero Section */
.hero {
  background: radial-gradient(circle at 80% 20%, rgba(6, 182, 212, 0.15), transparent 40%),
              linear-gradient(135deg, #022c22 0%, #064e3b 100%);
  color: #ffffff;
  padding: 100px 0 110px;
  position: relative;
  overflow: hidden;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: center;
}
.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid var(--emerald);
  color: var(--emerald-light);
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 0.82rem;
  font-weight: 600;
  margin-bottom: 20px;
}
.hero h2 {
  font-family: var(--font-sans);
  font-size: 3.2rem;
  line-height: 1.15;
  margin-bottom: 18px;
  letter-spacing: -1px;
}
.hero h2 span {
  background: linear-gradient(to right, var(--emerald), var(--cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero p {
  color: #94a3b8;
  font-size: 1.1rem;
  line-height: 1.7;
  margin-bottom: 30px;
}
.hero-btns {
  display: flex;
  gap: 15px;
  flex-wrap: wrap;
}
.btn-cyan {
  background: linear-gradient(135deg, var(--cyan), #0284c7);
  color: #ffffff;
  padding: 12px 26px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: none;
  cursor: pointer;
}
.hero-terminal {
  background: rgba(15, 23, 42, 0.8);
  border: 1px solid rgba(16, 185, 129, 0.3);
  border-radius: 12px;
  padding: 24px;
  box-shadow: var(--shadow-glow);
}
.terminal-bar {
  display: flex;
  gap: 6px;
  margin-bottom: 14px;
}
.dot { width: 10px; height: 10px; border-radius: 50%; }
.dot-red { background: #ef4444; }
.dot-yellow { background: #eab308; }
.dot-green { background: #10b981; }
.terminal-code {
  font-family: 'Courier New', Courier, monospace;
  font-size: 0.88rem;
  color: #38bdf8;
  line-height: 1.6;
}

/* STEM Pillars */
.section { padding: 80px 0; }
.section-center { text-align: center; max-width: 650px; margin: 0 auto 50px; }
.section-center h3 {
  font-family: var(--font-sans);
  font-size: 2.3rem;
  color: var(--primary-dark);
  letter-spacing: -0.5px;
  margin-bottom: 10px;
}
.section-center p { color: var(--slate-700); }

.stem-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 25px;
}
.stem-card {
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  padding: 30px;
  transition: all 0.3s;
  box-shadow: var(--shadow-sm);
}
.stem-card:hover {
  transform: translateY(-6px);
  border-color: var(--emerald);
  box-shadow: var(--shadow-glow);
}
.stem-icon {
  width: 56px;
  height: 56px;
  border-radius: 12px;
  background: var(--emerald-light);
  color: var(--forest-green);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
  margin-bottom: 20px;
}
.stem-card h4 {
  font-family: var(--font-sans);
  font-size: 1.25rem;
  margin-bottom: 10px;
  color: var(--slate-900);
}
.stem-card p {
  color: var(--slate-700);
  font-size: 0.92rem;
  line-height: 1.6;
}

/* Interactive Smart Fee Estimator (GuruDesk) */
.estimator-box {
  background: linear-gradient(135deg, #022c22, #064e3b);
  border-radius: 16px;
  padding: 45px;
  color: #ffffff;
  box-shadow: var(--shadow-lg);
  border: 1px solid rgba(16, 185, 129, 0.3);
}
.estimator-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 40px;
}
.control-item {
  margin-bottom: 20px;
}
.control-item label {
  display: block;
  font-size: 0.9rem;
  color: #a7f3d0;
  margin-bottom: 8px;
  font-weight: 500;
}
.range-slider {
  width: 100%;
  accent-color: var(--emerald);
}
.select-input {
  width: 100%;
  padding: 10px 14px;
  border-radius: 8px;
  border: 1px solid rgba(16, 185, 129, 0.4);
  background: rgba(15, 23, 42, 0.6);
  color: #ffffff;
  font-size: 0.95rem;
}
.calc-display {
  background: rgba(15, 23, 42, 0.7);
  border: 1px solid rgba(6, 182, 212, 0.3);
  border-radius: 12px;
  padding: 26px;
  box-shadow: var(--shadow-glow);
}
.calc-row {
  display: flex;
  justify-content: space-between;
  padding: 10px 0;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  font-size: 0.92rem;
  color: #cbd5e1;
}
.calc-total {
  border-top: 2px solid var(--emerald);
  padding-top: 15px;
  margin-top: 10px;
  display: flex;
  justify-content: space-between;
  font-size: 1.25rem;
  font-weight: 700;
  color: #34d399;
}

/* Footer */
.footer {
  background: #011c15;
  color: #94a3b8;
  padding: 60px 0 20px;
  border-top: 3px solid var(--emerald);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
  gap: 30px;
  margin-bottom: 40px;
}
.footer-col h4 {
  color: #ffffff;
  font-family: var(--font-sans);
  margin-bottom: 16px;
  font-size: 1.1rem;
}
.footer-col p { font-size: 0.9rem; }
.footer-col a { color: #94a3b8; text-decoration: none; font-size: 0.88rem; }
.footer-col a:hover { color: var(--emerald); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding-top: 20px;
  display: flex;
  justify-content: space-between;
  font-size: 0.82rem;
  flex-wrap: wrap;
}

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .stem-grid { grid-template-columns: 1fr; }
  .estimator-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .nav-links { display: none; }
}