/* ---------------------------------------------------------------------------
   LiteSchool marketing site — shared styles
   Self-contained, no external dependencies. System font stack for speed.
   --------------------------------------------------------------------------- */

:root {
  --brand: #2563eb;
  --brand-dark: #1d4ed8;
  --brand-tint: #eff4ff;
  --ink: #0f172a;
  --body: #334155;
  --muted: #64748b;
  --line: #e2e8f0;
  --bg: #ffffff;
  --bg-alt: #f8fafc;
  --radius: 14px;
  --shadow: 0 1px 3px rgba(15, 23, 42, 0.06), 0 8px 24px rgba(15, 23, 42, 0.05);
  --maxw: 1080px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--body);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { color: var(--ink); line-height: 1.2; margin: 0 0 0.5em; }
h1 { font-size: clamp(2rem, 5vw, 3.25rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); letter-spacing: -0.01em; }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1rem; }
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 1.25rem; }

/* --- Header / nav --- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
}
/* Offset anchored sections so their headings clear the sticky header. */
[id] { scroll-margin-top: 80px; }
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--ink);
}
.brand:hover { text-decoration: none; }
.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: var(--brand);
  color: #fff;
  font-weight: 800;
  font-size: 1rem;
}
.nav-links { display: flex; align-items: center; gap: 1.5rem; }
.nav-links a { color: var(--body); font-weight: 500; font-size: 0.95rem; }
.nav-links a:hover { color: var(--brand); text-decoration: none; }
.nav-links a.active { color: var(--brand); }

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.55rem 1.1rem;
  border-radius: 10px;
  border: 1px solid transparent;
  font: inherit;
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
}
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-dark); }
.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}
.btn:disabled:hover { background: var(--brand); }

/* --- Badge --- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.35rem 0.8rem;
  border-radius: 999px;
  background: var(--brand-tint);
  color: var(--brand-dark);
  font-size: 0.82rem;
  font-weight: 600;
}
.badge .dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--brand);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.18);
}

/* --- Hero --- */
.hero {
  padding: clamp(3rem, 8vw, 6rem) 0 clamp(2.5rem, 6vw, 4.5rem);
  background:
    radial-gradient(60% 120% at 100% 0%, var(--brand-tint) 0%, transparent 60%),
    var(--bg);
  text-align: center;
}
.hero p.lead {
  font-size: clamp(1.05rem, 2vw, 1.3rem);
  color: var(--muted);
  max-width: 620px;
  margin: 1rem auto 2rem;
}

/* --- Sections --- */
.section { padding: clamp(3rem, 7vw, 5rem) 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; max-width: 640px; margin: 0 auto 2.5rem; }
.section-head p { color: var(--muted); font-size: 1.05rem; }

/* --- Feature grid --- */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}
.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}
.card .icon {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 11px;
  background: var(--brand-tint);
  color: var(--brand);
  margin-bottom: 0.9rem;
}
.card .icon svg { width: 22px; height: 22px; }
.card h3 { margin-bottom: 0.35rem; }
.card p { color: var(--muted); margin: 0; font-size: 0.95rem; }

/* --- Split / prose --- */
.prose { max-width: 720px; margin: 0 auto; }
.prose h2 { margin-top: 2rem; }
.prose ul { padding-left: 1.2rem; }
.prose li { margin-bottom: 0.4rem; }

/* --- Callout / coming soon --- */
.callout {
  background: linear-gradient(135deg, var(--brand) 0%, var(--brand-dark) 100%);
  color: #fff;
  border-radius: var(--radius);
  padding: clamp(2rem, 5vw, 3rem);
  text-align: center;
}
.callout h2 { color: #fff; }
.callout p { color: rgba(255, 255, 255, 0.9); max-width: 520px; margin: 0.5rem auto 0; }
.callout a { color: #fff; text-decoration: underline; }

/* --- Footer --- */
.site-footer {
  border-top: 1px solid var(--line);
  background: var(--bg-alt);
  padding: 2.5rem 0;
  margin-top: 2rem;
}
.footer-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}
.footer-links { display: flex; gap: 1.25rem; flex-wrap: wrap; }
.footer-links a { color: var(--muted); font-size: 0.9rem; }
.footer-copy { color: var(--muted); font-size: 0.85rem; }

/* --- Responsive nav --- */
@media (max-width: 640px) {
  .nav-links { gap: 1rem; }
}