:root {
  --blue: #2563eb;
  --blue-dark: #1d4ed8;
  --ink: #111827;
  --gray: #4b5563;
  --line: #e5e7eb;
  --bg: #f8fafc;
  --card: #ffffff;
  --radius: 14px;
}

* { box-sizing: border-box; }

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

a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }

header.site {
  background: linear-gradient(120deg, var(--blue), var(--blue-dark));
  color: #fff;
  padding: 18px 24px;
}

.site-header-inner {
  max-width: 1080px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.brand {
  font-size: 1.3rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: 0.2px;
}
.brand span { opacity: 0.85; font-weight: 500; }

nav.main-nav { display: flex; gap: 20px; flex-wrap: wrap; }
nav.main-nav a {
  color: #eaf1ff;
  font-weight: 600;
  font-size: 0.95rem;
}
nav.main-nav a:hover { color: #fff; }

main { max-width: 1080px; margin: 0 auto; padding: 40px 24px 80px; }

.hero {
  text-align: center;
  padding: 56px 20px 48px;
}
.hero h1 {
  font-size: 2.4rem;
  margin: 0 0 14px;
  color: var(--ink);
}
.hero p.lead {
  font-size: 1.15rem;
  color: var(--gray);
  max-width: 640px;
  margin: 0 auto 28px;
}
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.95rem;
}
.btn-primary { background: var(--blue); color: #fff; }
.btn-primary:hover { background: var(--blue-dark); text-decoration: none; }
.btn-ghost { background: #fff; color: var(--blue); border: 1.5px solid var(--blue); }
.btn-ghost:hover { background: #eef4ff; text-decoration: none; }

.section { padding: 40px 0; }
.section h2 {
  font-size: 1.6rem;
  margin-bottom: 8px;
}
.section p.section-lead {
  color: var(--gray);
  margin-top: 0;
  margin-bottom: 28px;
  max-width: 680px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 18px;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
}
.card h3 { margin: 0 0 8px; font-size: 1.05rem; }
.card p { margin: 0; color: var(--gray); font-size: 0.94rem; }
.card .tag {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--blue);
  background: #eef4ff;
  padding: 3px 10px;
  border-radius: 999px;
  margin-bottom: 10px;
}

.pathways .card { text-align: left; }

.course-banner {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}
.course-banner h3 { margin: 0 0 6px; font-size: 1.3rem; }
.course-banner p { margin: 0; color: var(--gray); }

.breadcrumb {
  font-size: 0.9rem;
  color: var(--gray);
  margin-bottom: 20px;
}
.breadcrumb a { color: var(--blue); }

.lesson-list {
  list-style: none;
  padding: 0;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.lesson-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--line);
  background: var(--card);
}
.lesson-list li:last-child { border-bottom: none; }
.lesson-list .lesson-name { font-weight: 600; }
.lesson-list .lesson-meta { color: var(--gray); font-size: 0.85rem; }
.status-pill {
  font-size: 0.72rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 0.4px;
}
.status-available { background: #e8f8ee; color: #0f7a3d; }
.status-locked { background: #f1f2f4; color: #6b7280; }

.lesson-body h2 { margin-top: 40px; }
.lesson-body h3 { margin-top: 28px; }
.lesson-body ul, .lesson-body ol { padding-left: 22px; }

.callout {
  background: #eef4ff;
  border-left: 4px solid var(--blue);
  padding: 16px 20px;
  border-radius: 8px;
  margin: 24px 0;
}
.callout strong { color: var(--blue-dark); }

.quiz {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  margin-top: 32px;
}
.quiz h3 { margin-top: 0; }
.quiz label {
  display: block;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  margin-bottom: 8px;
  cursor: pointer;
}
.quiz label:hover { background: #f8fafc; }
#quiz-result { margin-top: 14px; font-weight: 700; }

.lesson-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.lesson-nav .disabled { color: #9ca3af; cursor: not-allowed; }

footer.site {
  text-align: center;
  padding: 28px 20px;
  color: var(--gray);
  font-size: 0.88rem;
  border-top: 1px solid var(--line);
}