:root {
  --indigo-brand: #6366f1;
  --indigo-dark: #4f46e5;
  --indigo-light: #a5b4fc;
  --bg-deep: #0f172a;
  --bg-box: #1e293b;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
}

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

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg-deep);
  color: var(--text-primary);
  line-height: 1.6;
}

.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Header */
.header {
  background: rgba(15, 23, 42, 0.95);
  border-bottom: 1px solid #334155;
  padding: 1.2rem 0;
  position: sticky;
  top: 0;
  z-index: 50;
}

.nav-wrap {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--indigo-light);
  text-decoration: none;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.5rem;
}

.nav {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.nav a {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
}

.nav a:hover {
  color: var(--indigo-light);
}

.btn-enroll {
  background: var(--indigo-brand);
  color: #fff !important;
  padding: 0.5rem 1.25rem;
  border-radius: 0.5rem;
  font-weight: 600 !important;
}

/* Hero */
.hero {
  padding: 5rem 0;
  background: radial-gradient(circle at 80% 20%, #312e81 0%, var(--bg-deep) 70%);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 3rem;
  align-items: center;
}

.badge {
  display: inline-block;
  background: rgba(99, 102, 241, 0.15);
  color: var(--indigo-light);
  border: 1px solid rgba(99, 102, 241, 0.3);
  font-weight: 700;
  font-size: 0.85rem;
  padding: 0.3rem 0.85rem;
  border-radius: 9999px;
  margin-bottom: 1rem;
}

.hero h1 {
  font-size: 2.75rem;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 1.25rem;
}

.hero p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 2rem;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.8rem 1.75rem;
  border-radius: 0.5rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
}

.btn-indigo {
  background: var(--indigo-brand);
  color: #fff;
  border: none;
}

.btn-indigo:hover {
  background: var(--indigo-dark);
}

.btn-outline {
  border: 1px solid #475569;
  color: #fff;
}

.hero-svg {
  width: 100%;
  height: auto;
  border-radius: 1rem;
}

/* Curriculum */
.curriculum {
  padding: 5rem 0;
  background: #131d33;
}

.sec-header {
  text-align: center;
  margin-bottom: 3.5rem;
}

.sec-header .sub {
  color: var(--indigo-light);
  font-weight: 700;
  text-transform: uppercase;
  font-size: 0.85rem;
}

.sec-header h2 {
  font-size: 2.25rem;
  font-weight: 800;
  margin-top: 0.5rem;
}

.modules-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.module-card {
  background: var(--bg-box);
  padding: 2.25rem 2rem;
  border-radius: 1rem;
  border: 1px solid #334155;
}

.mod-num {
  display: inline-block;
  color: var(--indigo-light);
  font-size: 0.85rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
}

.module-card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}

.module-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* Enroll */
.enroll {
  padding: 5rem 0;
}

.enroll-box {
  max-width: 680px;
  margin: 0 auto;
  background: var(--bg-box);
  padding: 3rem 2.5rem;
  border-radius: 1.25rem;
  text-align: center;
  border: 1px solid #334155;
}

.enroll-box h2 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.enroll-box p {
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.enroll-form {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.enroll-form input,
.enroll-form select {
  padding: 0.85rem 1rem;
  border-radius: 0.5rem;
  border: 1px solid #475569;
  background: var(--bg-deep);
  color: #fff;
  font-size: 0.95rem;
  outline: none;
}

.btn-block {
  width: 100%;
}

/* Footer */
.footer {
  padding: 2.5rem 0;
  border-top: 1px solid #1e293b;
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

@media (max-width: 768px) {
  .nav-toggle { display: block; }
  .nav {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: var(--bg-deep);
    padding: 1.5rem;
  }
  .nav.active { display: flex; }
  .hero-grid { grid-template-columns: 1fr; text-align: center; }
  .hero-btns { justify-content: center; }
  .modules-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
}