:root{
  --bg:#0b0f14;
  --panel:#0f1620;
  --text:#e8edf2;
  --muted:#a9b4bf;
  --brand:#7dd3fc;
  --brand2:#a7f3d0;
  --border: rgba(255,255,255,.10);
  --shadow: 0 10px 30px rgba(0,0,0,.35);
  --radius: 18px;
  --max: 1120px;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, "Apple Color Emoji","Segoe UI Emoji";
  background: radial-gradient(1200px 800px at 20% 10%, rgba(125,211,252,.10), transparent 55%),
              radial-gradient(1000px 700px at 80% 20%, rgba(167,243,208,.08), transparent 60%),
              var(--bg);
  color:var(--text);
  line-height:1.55;
}
a{color:var(--brand); text-decoration:none}
a:hover{text-decoration:underline}
.container{max-width:var(--max); margin:0 auto; padding:24px}
.topbar{
  position:sticky; top:0; z-index:10;
  background: rgba(11,15,20,.75);
  backdrop-filter: blur(10px);
  border-bottom:1px solid var(--border);
}
.brand{display:flex; align-items:center; gap:12px;}
.logo{
  width:40px; height:40px; border-radius:12px;
  background: linear-gradient(135deg, rgba(125,211,252,.35), rgba(167,243,208,.30));
  border:1px solid var(--border);
  box-shadow: var(--shadow);
}
.brand h1{font-size:16px; margin:0}
.brand p{margin:0; font-size:12px; color:var(--muted)}
.nav{display:flex; flex-wrap:wrap; gap:10px; justify-content:flex-end;}
.nav a{
  padding:10px 12px; border:1px solid transparent; border-radius:999px;
  color:var(--text); font-weight:600; font-size:14px; opacity:.92;
}
.nav a:hover{border-color:var(--border); text-decoration:none}
.nav a.active{
  border-color: rgba(125,211,252,.35);
  background: rgba(125,211,252,.08);
}
.hero{padding:52px 0 18px 0}
.kicker{
  display:inline-flex; gap:10px; align-items:center;
  border:1px solid rgba(125,211,252,.25);
  background: rgba(125,211,252,.08);
  padding:8px 12px; border-radius:999px;
  color:var(--text); font-weight:700; font-size:13px;
}
.kicker span{color:var(--muted); font-weight:700}
.hero h2{font-size:44px; line-height:1.1; margin:14px 0 10px 0}
.hero p{font-size:18px; color:var(--muted); max-width:70ch; margin:0 0 18px 0}
.cta-row{display:flex; flex-wrap:wrap; gap:12px; margin-top:18px}
.btn{
  display:inline-flex; align-items:center; justify-content:center; gap:10px;
  padding:12px 16px; border-radius:12px; border:1px solid var(--border);
  background: rgba(255,255,255,.04); color:var(--text);
  font-weight:800; font-size:14px;
}
.btn.primary{
  background: linear-gradient(135deg, rgba(125,211,252,.25), rgba(167,243,208,.18));
  border-color: rgba(125,211,252,.25);
}
.btn:hover{transform: translateY(-1px); text-decoration:none}
.small{font-size:13px; color:var(--muted)}
.grid{
  display:grid;
  grid-template-columns: repeat(12, 1fr);
  gap:16px;
  margin: 18px 0 34px 0;
}
.card{
  grid-column: span 12;
  background: rgba(255,255,255,.03);
  border:1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding:18px;
}
.card h3{margin:0 0 6px 0; font-size:18px}
.card p{margin:0 0 10px 0; color:var(--muted)}
.card ul{margin:10px 0 0 18px; color:var(--muted)}
.pillrow{display:flex; flex-wrap:wrap; gap:8px; margin-top:10px}
.pill{
  padding:6px 10px; border-radius:999px;
  border:1px solid rgba(255,255,255,.10);
  background: rgba(255,255,255,.03);
  color:var(--muted); font-weight:700; font-size:12px;
}
@media(min-width: 860px){
  .hero h2{font-size:54px}
  .span-7{grid-column: span 7}
  .span-5{grid-column: span 5}
  .span-6{grid-column: span 6}
  .span-4{grid-column: span 4}
}
.section-title{font-size:22px; margin: 10px 0 6px 0}
hr.sep{border:0; border-top:1px solid var(--border); margin: 18px 0}
.footer{
  border-top:1px solid var(--border);
  margin-top: 42px; padding: 22px 0 40px 0;
  color:var(--muted); font-size:13px;
}
.notice{
  padding:12px 14px;
  background: rgba(167,243,208,.07);
  border: 1px solid rgba(167,243,208,.18);
  border-radius: 14px;
  color: var(--text);
}
.notice strong{color: var(--brand2)}

/* v1.2 course UI additions */
.course-grid{display:grid; grid-template-columns: repeat(12,1fr); gap:16px; margin: 18px 0 34px 0;}
.course-card{grid-column: span 12; background: rgba(255,255,255,.03); border:1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); padding:18px;}
@media(min-width:860px){ .course-card.span-4{grid-column: span 4} .course-card.span-8{grid-column: span 8} .course-card.span-6{grid-column: span 6}}
.toc{border:1px solid var(--border); border-radius: var(--radius); background: rgba(255,255,255,.02); padding:14px;}
.toc a{display:block; padding:8px 10px; border-radius:12px; color: var(--text);}
.toc a:hover{background: rgba(255,255,255,.04); text-decoration:none}
.breadcrumbs{font-size:13px; color: var(--muted); margin: 10px 0 0 0;}
.lesson-meta{display:flex; flex-wrap:wrap; gap:10px; margin-top:10px}
.callout{padding:14px; border-radius: 14px; border: 1px solid rgba(125,211,252,.22); background: rgba(125,211,252,.06); color: var(--text); margin: 14px 0;}
.codeblock{background: rgba(0,0,0,.25); border:1px solid var(--border); border-radius: 14px; padding: 12px; overflow:auto; color: var(--text);}
.nextprev{display:flex; flex-wrap:wrap; gap:10px; justify-content:space-between; margin-top:16px}
.badge{display:inline-flex; align-items:center; gap:8px; padding:6px 10px; border-radius:999px; border:1px solid rgba(167,243,208,.22); background: rgba(167,243,208,.06); color: var(--text); font-weight:800; font-size:12px;}

/* ===== Course Polish v1.3 ===== */
.course-hero{margin-bottom:28px}
.lesson-card{border:1px solid #e5e7eb;border-radius:12px;padding:16px;margin-bottom:14px}
.learning-objectives{border-left:4px solid #60a5fa;padding-left:14px;margin:18px 0}
.capstone{border:1px dashed #34d399;border-radius:12px;padding:16px;background:#ecfdf5}

/* v1.4.0: Cohort / enterprise pricing layout */
.pricing-grid{
  display:grid;
  grid-template-columns: repeat(12, 1fr);
  gap:14px;
  margin-top:14px;
}
.pricing-card{
  grid-column: span 4;
  border:1px solid rgba(255,255,255,.10);
  border-radius:16px;
  padding:16px;
  background: rgba(255,255,255,.03);
}
.pricing-card h3{ margin-top:0; }
.price{
  font-size:28px;
  font-weight:800;
  margin:8px 0;
  color: var(--text);
}
.price .unit{ font-size:12px; font-weight:600; opacity:.8; margin-left:6px; }
.pricing-card ul{ margin:10px 0 0 18px; }
.pricing-card .cta-row{ margin-top:12px; }
@media (max-width: 900px){
  .pricing-card{ grid-column: span 12; }
}

/* v1.4.5: Local progress UI */
.progress-wrap{ margin-top:12px; }
.progress-bar{ height:10px; border-radius:999px; background: rgba(255,255,255,.08); overflow:hidden; border:1px solid rgba(255,255,255,.10); }
.progress-bar > div{ height:100%; width:0%; background: rgba(255,255,255,.35); }
.progress-meta{ display:flex; justify-content:space-between; gap:12px; margin-top:8px; align-items:center; }
a.done{ opacity:.95; }
.puf-check{ opacity:.9; }
.progress-panel{ border:1px solid rgba(255,255,255,.10); border-radius:16px; padding:14px; background: rgba(255,255,255,.03); }
.chip{ display:inline-block; padding:4px 10px; border-radius:999px; font-size:12px; font-weight:700; border:1px solid rgba(255,255,255,.14); background: rgba(255,255,255,.04); }

/* v1.4.6: Library UI */
.library-controls{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  align-items:center;
  margin: 12px 0;
}
.library-controls input, .library-controls select{
  background: rgba(255,255,255,.03);
  border:1px solid rgba(255,255,255,.12);
  border-radius:12px;
  padding:10px 12px;
  color: var(--text);
  min-width: 220px;
}
.library-controls label{
  font-size:12px;
  opacity:.85;
}

/* v1.4.7: Library collections */
[data-collections] .pricing-card ul li a{ text-decoration: underline; }

/* v1.4.8: Recommended Next */
.next-panel{
  border:1px solid rgba(255,255,255,.10);
  border-radius:16px;
  padding:14px;
  background: rgba(255,255,255,.02);
  margin: 14px 0;
}
.next-panel h4{ margin: 0 0 8px 0; }
.next-grid{
  display:grid;
  grid-template-columns: repeat(12, 1fr);
  gap:10px;
}
.next-card{
  grid-column: span 6;
  border:1px solid rgba(255,255,255,.10);
  border-radius:14px;
  padding:12px;
  background: rgba(255,255,255,.02);
}
.next-card p{ margin: 6px 0 10px 0; }
@media (max-width: 860px){
  .next-card{ grid-column: span 12; }
}

/* v1.5.2: Accessibility + UX */
.skip-link{
  position:absolute;
  left:-9999px;
  top:auto;
  width:1px;
  height:1px;
  overflow:hidden;
}
.skip-link:focus{
  left:16px;
  top:14px;
  width:auto;
  height:auto;
  padding:10px 12px;
  border-radius:12px;
  background: rgba(255,255,255,.08);
  border:1px solid rgba(255,255,255,.18);
  z-index: 9999;
}
:focus-visible{
  outline: 3px solid rgba(255,255,255,.55);
  outline-offset: 3px;
  border-radius: 10px;
}
@media (prefers-reduced-motion: reduce){
  *{ scroll-behavior:auto !important; transition:none !important; animation:none !important; }
}

/* v1.5.3: Certificate sheet + print */
.cert-sheet{
  margin-top: 14px;
  border:1px solid rgba(255,255,255,.10);
  border-radius:18px;
  background: rgba(255,255,255,.02);
  padding: 14px;
}
.cert-border{
  border: 2px solid rgba(255,255,255,.18);
  border-radius: 16px;
  padding: 22px 18px;
  text-align:center;
}
@media print{
  .topbar, .footer, .nav, .cta-row, .skip-link, .notice, [data-cert-controls], [data-cert-eligibility-wrap]{ display:none !important; }
  body{ background:#fff !important; color:#000 !important; }
  .container{ width: 100% !important; max-width: 100% !important; }
  .cert-sheet{ border:none !important; background:#fff !important; padding:0 !important; }
  .cert-border{ border: 2px solid #111 !important; color:#000 !important; }
  a{ color:#000 !important; text-decoration:none !important; }
}


/* v1.7.9 Course icons */
.course-icon{width:44px;height:44px;flex:0 0 44px;border-radius:12px;}
.card-header{display:flex;align-items:center;gap:12px;}
.card-header h3,.card-header h4{margin:0;}


/* v1.7.19 — Sticky Enterprise CTA (no tracking, local dismiss only) */
.sticky-cta{
  position:fixed;
  left:12px;
  right:12px;
  bottom:12px;
  z-index:9999;
  background:rgba(15,22,32,.92);
  border:1px solid var(--border);
  border-radius:16px;
  box-shadow:0 12px 40px rgba(0,0,0,.45);
  padding:10px 12px;
  backdrop-filter:saturate(120%) blur(6px);
}
.sticky-cta .row{display:flex; align-items:center; justify-content:space-between; gap:10px; flex-wrap:wrap;}
.sticky-cta .msg{display:flex; align-items:center; gap:10px; min-width:240px;}
.sticky-cta .msg .dot{width:10px; height:10px; border-radius:999px; background:var(--accent);}
.sticky-cta .msg strong{font-weight:700;}
.sticky-cta .actions{display:flex; gap:8px; flex-wrap:wrap; align-items:center;}
.sticky-cta .actions a{white-space:nowrap;}
.sticky-cta .close{
  background:transparent;
  border:1px solid var(--border);
  color:var(--text);
  border-radius:999px;
  padding:8px 10px;
  cursor:pointer;
}
@media (min-width: 980px){
  .sticky-cta{left:24px; right:24px; bottom:18px;}
}
@media print{
  .sticky-cta{display:none !important;}
}