:root {
  --bg: #0e0f1a;
  --bg-2: #15172a;
  --surface: #1b1e36;
  --surface-2: #232746;
  --line: #2e3358;
  --text: #eef0ff;
  --muted: #a3a8cc;
  --primary: #7c6cff;
  --primary-2: #9d7bff;
  --accent: #34d8c4;
  --gold: #ffcd6b;
  --danger: #ff6b7a;
  --good: #45d483;
  --radius: 16px;
  --shadow: 0 18px 50px -20px rgba(0, 0, 0, 0.7);
  --maxw: 980px;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: radial-gradient(1200px 600px at 80% -10%, #25204a 0%, transparent 60%),
              radial-gradient(900px 500px at -10% 10%, #14304a 0%, transparent 55%),
              var(--bg);
  color: var(--text);
  font-family: 'Heebo', 'Inter', system-ui, sans-serif;
  line-height: 1.65;
  min-height: 100vh;
}
html[dir='ltr'] body { font-family: 'Inter', 'Heebo', system-ui, sans-serif; }
a { color: inherit; text-decoration: none; }

/* ---------- topbar ---------- */
.topbar {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; gap: 18px;
  padding: 12px max(18px, calc((100% - var(--maxw)) / 2));
  background: rgba(14, 15, 26, 0.82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-mark {
  width: 38px; height: 38px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 11px; font-size: 18px; color: #fff;
  box-shadow: 0 6px 18px -6px var(--primary);
}
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text strong { font-size: 15px; }
.brand-text small { color: var(--muted); font-size: 11px; }
.nav { display: flex; gap: 6px; margin-inline-start: auto; }
.nav a {
  padding: 7px 13px; border-radius: 9px; font-size: 14px; color: var(--muted);
  transition: .15s;
}
.nav a:hover { color: var(--text); background: var(--surface); }
.topbar-right { display: flex; align-items: center; gap: 12px; }
.mini-progress { display: flex; align-items: center; gap: 7px; }
.mini-bar { width: 64px; height: 6px; background: var(--surface-2); border-radius: 99px; overflow: hidden; }
.mini-bar span { display: block; height: 100%; background: linear-gradient(90deg, var(--primary), var(--accent)); transition: width .4s; }
.mini-progress em { font-style: normal; font-size: 12px; color: var(--muted); }
.lang-toggle {
  border: 1px solid var(--line); background: var(--surface); color: var(--text);
  width: 40px; height: 32px; border-radius: 9px; cursor: pointer; font-weight: 700; font-size: 13px;
  transition: .15s;
}
.lang-toggle:hover { border-color: var(--primary); color: var(--primary-2); }

/* ---------- layout ---------- */
.main { max-width: var(--maxw); margin: 0 auto; padding: 26px 18px 60px; }
.page-title { font-size: clamp(24px, 4vw, 34px); margin: 6px 0 14px; }

/* ---------- hero ---------- */
.hero {
  border-radius: 24px; padding: 46px 34px;
  background: linear-gradient(135deg, rgba(124,108,255,.18), rgba(52,216,196,.10)), var(--surface);
  border: 1px solid var(--line); box-shadow: var(--shadow);
  position: relative; overflow: hidden;
}
.hero::after {
  content: ''; position: absolute; inset-inline-end: -60px; top: -60px;
  width: 220px; height: 220px; border-radius: 50%;
  background: radial-gradient(circle, rgba(124,108,255,.4), transparent 70%);
}
.eyebrow { color: var(--muted); font-size: 15px; max-width: 620px; margin: 0 0 10px; }
.hero h1 { font-size: clamp(28px, 5.5vw, 48px); line-height: 1.15; margin: 0 0 22px; max-width: 720px; font-weight: 800; }
.hero-stats { display: flex; gap: 28px; margin-bottom: 26px; flex-wrap: wrap; }
.hero-stats div { display: flex; flex-direction: column; }
.hero-stats strong { font-size: 30px; color: var(--accent); }
.hero-stats span { color: var(--muted); font-size: 13px; }
.hero-cta { display: flex; gap: 12px; flex-wrap: wrap; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 7px; justify-content: center;
  padding: 12px 22px; border-radius: 12px; font-weight: 700; font-size: 15px;
  cursor: pointer; border: 1px solid transparent; transition: .16s; font-family: inherit;
}
.btn-sm { padding: 8px 16px; font-size: 13px; }
.btn-primary { background: linear-gradient(135deg, var(--primary), var(--primary-2)); color: #fff; box-shadow: 0 10px 24px -10px var(--primary); }
.btn-primary:hover { transform: translateY(-1px); filter: brightness(1.08); }
.btn-ghost { background: var(--surface); border-color: var(--line); color: var(--text); }
.btn-ghost:hover { border-color: var(--primary); }
.btn-done { background: rgba(69,212,131,.14); color: var(--good); border-color: rgba(69,212,131,.4); }
.btn-danger { background: rgba(255,107,122,.12); color: var(--danger); border-color: rgba(255,107,122,.35); }
.btn-danger:hover { background: rgba(255,107,122,.2); }

/* ---------- module cards (home) ---------- */
.modules-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; margin-top: 22px; }
.module-card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px; transition: .18s; position: relative; overflow: hidden;
}
.module-card:hover { transform: translateY(-3px); border-color: var(--primary); }
.module-num {
  width: 34px; height: 34px; border-radius: 10px; display: grid; place-items: center;
  background: var(--surface-2); color: var(--accent); font-weight: 800; margin-bottom: 12px;
}
.module-card h3 { margin: 0 0 8px; font-size: 18px; }
.module-card p { margin: 0 0 16px; color: var(--muted); font-size: 14px; }
.bar { height: 7px; background: var(--surface-2); border-radius: 99px; overflow: hidden; margin-bottom: 7px; }
.bar span { display: block; height: 100%; background: linear-gradient(90deg, var(--primary), var(--accent)); transition: width .4s; }
.module-card small { color: var(--muted); font-size: 12px; }

/* ---------- curriculum accordion ---------- */
.module-block { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); margin-bottom: 16px; overflow: hidden; }
.module-head { display: flex; align-items: center; gap: 16px; padding: 20px 22px; border-bottom: 1px solid var(--line); }
.module-head-num { width: 40px; height: 40px; flex: none; border-radius: 11px; display: grid; place-items: center; background: linear-gradient(135deg, var(--primary), var(--accent)); color: #fff; font-weight: 800; }
.module-head-text { flex: 1; }
.module-head-text h3 { margin: 0 0 3px; font-size: 18px; }
.module-head-text p { margin: 0; color: var(--muted); font-size: 13px; }
.lesson-list { list-style: none; margin: 0; padding: 8px; }
.lesson-row {
  display: flex; align-items: center; gap: 14px; padding: 13px 14px; border-radius: 11px; transition: .14s;
}
.lesson-row:hover { background: var(--surface-2); }
.lesson-check {
  width: 30px; height: 30px; flex: none; border-radius: 8px; display: grid; place-items: center;
  background: var(--surface-2); color: var(--muted); font-size: 13px; font-weight: 700;
}
.lesson-row.done .lesson-check { background: rgba(69,212,131,.16); color: var(--good); }
.lesson-name { flex: 1; font-weight: 500; }
.lesson-meta { color: var(--muted); font-size: 12px; }

/* progress ring */
.ring {
  --pct: 0; width: 52px; height: 52px; border-radius: 50%; display: grid; place-items: center; flex: none;
  background: conic-gradient(var(--accent) calc(var(--pct) * 1%), var(--surface-2) 0);
}
.ring span { width: 40px; height: 40px; border-radius: 50%; background: var(--surface); display: grid; place-items: center; font-size: 12px; font-weight: 700; }
.ring.big { width: 110px; height: 110px; }
.ring.big span { width: 86px; height: 86px; font-size: 20px; }

/* ---------- lesson ---------- */
.back { color: var(--muted); font-size: 14px; display: inline-block; margin-bottom: 14px; }
.back:hover { color: var(--primary-2); }
.lesson-eyebrow { color: var(--accent); font-size: 13px; font-weight: 700; margin: 0 0 2px; letter-spacing: .04em; }
.lesson-sub { color: var(--muted); font-size: 13px; margin: -6px 0 20px; }
.objectives { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 22px; margin-bottom: 24px; }
.objectives h4 { margin: 0 0 10px; font-size: 14px; color: var(--accent); }
.objectives ul { margin: 0; padding-inline-start: 20px; }
.objectives li { color: var(--muted); margin-bottom: 5px; }

.content { font-size: 16px; }
.c-p { margin: 0 0 16px; }
.c-h { font-size: 20px; margin: 26px 0 12px; }
.c-list { margin: 0 0 18px; padding-inline-start: 22px; }
.c-list li { margin-bottom: 8px; }
.c-quote {
  margin: 22px 0; padding: 18px 22px; border-inline-start: 4px solid var(--gold);
  background: var(--surface); border-radius: 12px; font-size: 17px; font-style: italic;
}
.c-quote cite { display: block; margin-top: 8px; font-size: 13px; color: var(--muted); font-style: normal; }
.c-tip {
  display: flex; gap: 12px; align-items: flex-start;
  background: linear-gradient(135deg, rgba(52,216,196,.1), transparent); border: 1px solid rgba(52,216,196,.3);
  border-radius: 12px; padding: 14px 16px; margin: 18px 0;
}
.c-tip-tag { background: var(--accent); color: #06231f; font-weight: 800; font-size: 11px; padding: 3px 9px; border-radius: 7px; flex: none; margin-top: 3px; }
.c-tip p { margin: 0; }

/* ---------- exercises ---------- */
.exercises { margin-top: 34px; }
.ex-section-title { font-size: 20px; margin: 0 0 16px; padding-bottom: 10px; border-bottom: 1px dashed var(--line); }
.ex { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px 22px; margin-bottom: 16px; }
.ex-head { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; flex-wrap: wrap; }
.ex-badge {
  background: linear-gradient(135deg, var(--primary), var(--primary-2)); color: #fff;
  font-size: 11px; font-weight: 800; padding: 4px 11px; border-radius: 8px; letter-spacing: .03em; flex: none;
}
.ex-head h4 { margin: 0; font-size: 16px; }
.ex-intro { color: var(--muted); font-size: 14px; margin: 0 0 14px; }
.ex-textarea {
  width: 100%; background: var(--bg-2); border: 1px solid var(--line); border-radius: 11px;
  color: var(--text); padding: 12px 14px; font-family: inherit; font-size: 15px; resize: vertical; line-height: 1.6;
}
.ex-textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(124,108,255,.18); }
.ex-foot { min-height: 18px; margin-top: 6px; text-align: end; }
.save-hint { color: var(--good); font-size: 12px; font-weight: 600; }

.ws-grid { display: grid; gap: 14px; }
.ws-field { display: flex; flex-direction: column; gap: 6px; }
.ws-field > span { font-weight: 600; font-size: 14px; }

/* quiz */
.quiz-opts { display: grid; gap: 10px; }
.quiz-opt {
  display: flex; align-items: center; gap: 12px; text-align: start; cursor: pointer;
  background: var(--bg-2); border: 1px solid var(--line); border-radius: 11px; padding: 12px 14px;
  color: var(--text); font-family: inherit; font-size: 15px; transition: .14s;
}
.quiz-opt:hover { border-color: var(--primary); }
.quiz-letter { width: 26px; height: 26px; flex: none; border-radius: 7px; background: var(--surface-2); display: grid; place-items: center; font-weight: 800; font-size: 13px; }
.quiz-opt.sel.right { border-color: var(--good); background: rgba(69,212,131,.12); }
.quiz-opt.sel.right .quiz-letter { background: var(--good); color: #06231f; }
.quiz-opt.sel.wrong { border-color: var(--danger); background: rgba(255,107,122,.1); }
.quiz-opt.sel.wrong .quiz-letter { background: var(--danger); color: #2a0a0f; }
.quiz-feedback { display: none; margin-top: 12px; padding: 11px 14px; border-radius: 10px; font-size: 14px; }
.quiz-feedback.show { display: block; }
.quiz-feedback.ok { background: rgba(69,212,131,.12); color: var(--good); }
.quiz-feedback.no { background: rgba(255,107,122,.1); color: var(--danger); }

/* timer */
.timer { display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
.timer-display { font-size: 40px; font-weight: 800; font-variant-numeric: tabular-nums; color: var(--accent); letter-spacing: .04em; }
.timer-display.ding { animation: ding .5s ease 2; color: var(--gold); }
@keyframes ding { 0%,100% { transform: scale(1); } 50% { transform: scale(1.12); } }
.timer-btns { display: flex; gap: 8px; }

/* checklist */
.checklist { display: grid; gap: 8px; }
.check-item {
  display: flex; align-items: center; gap: 12px; cursor: pointer; padding: 11px 14px;
  background: var(--bg-2); border: 1px solid var(--line); border-radius: 11px; transition: .14s;
}
.check-item:hover { border-color: var(--primary); }
.check-item input { display: none; }
.check-box {
  width: 24px; height: 24px; flex: none; border-radius: 7px; border: 2px solid var(--line);
  display: grid; place-items: center; color: transparent; font-weight: 800; font-size: 14px; transition: .14s;
}
.check-item.checked { border-color: rgba(69,212,131,.4); background: rgba(69,212,131,.08); }
.check-item.checked .check-box { background: var(--good); border-color: var(--good); color: #06231f; }
.check-item.checked > span:last-child { color: var(--muted); text-decoration: line-through; }

/* complete + nav */
.complete-row { margin: 30px 0 18px; }
.lesson-nav { display: flex; justify-content: space-between; gap: 12px; margin-top: 10px; }

/* progress page */
.prog-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 16px; margin-bottom: 24px; }
.prog-card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; text-align: center; display: flex; flex-direction: column; align-items: center; gap: 10px; }
.prog-card p { margin: 0; color: var(--muted); font-size: 14px; }
.prog-card.stat strong { font-size: 38px; font-weight: 800; color: var(--accent); }
.prog-card.stat strong small { font-size: 18px; color: var(--muted); font-weight: 600; }
.prog-modules { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 22px; }
.prog-mod-row { display: flex; align-items: center; gap: 14px; padding: 9px 0; }
.prog-mod-name { flex: none; width: 40%; font-size: 14px; }
.prog-mod-row .bar { flex: 1; margin: 0; }
.prog-mod-pct { color: var(--muted); font-size: 13px; flex: none; }
.empty { color: var(--muted); background: var(--surface); border: 1px dashed var(--line); border-radius: 12px; padding: 18px; }
.danger-row { margin-top: 24px; text-align: center; }

.footer { text-align: center; color: var(--muted); font-size: 12px; padding: 24px; border-top: 1px solid var(--line); }

@media (max-width: 760px) {
  .topbar { flex-wrap: wrap; gap: 10px 14px; padding: 10px 14px; }
  .nav {
    order: 3; width: 100%; margin-inline-start: 0;
    overflow-x: auto; -webkit-overflow-scrolling: touch;
    padding-bottom: 2px; gap: 4px;
  }
  .nav::-webkit-scrollbar { height: 0; }
  .nav a { white-space: nowrap; font-size: 13px; padding: 6px 10px; }
  .topbar-right { margin-inline-start: auto; }
  .hero { padding: 32px 22px; }
  .prog-mod-name { width: 50%; }
  .timer-display { font-size: 32px; }
  .course-pick { grid-template-columns: 1fr; }
}

/* ============ course select ============ */
.select-hero { text-align: center; padding: 28px 16px 8px; }
.select-hero .eyebrow { margin: 0 auto 10px; }
.select-hero h1 { font-size: clamp(26px, 5vw, 40px); margin: 0; }
.course-pick { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin-top: 22px; }
.pick-card {
  position: relative; overflow: hidden;
  background: var(--surface); border: 1px solid var(--line); border-radius: 22px;
  padding: 30px 28px; transition: .2s; display: flex; flex-direction: column; gap: 12px;
}
.pick-card::before {
  content: ''; position: absolute; inset: 0 0 auto 0; height: 6px;
  background: linear-gradient(90deg, var(--c), var(--c2));
}
.pick-card:hover { transform: translateY(-4px); border-color: var(--c); box-shadow: 0 24px 50px -24px var(--c); }
.pick-icon {
  width: 64px; height: 64px; border-radius: 18px; display: grid; place-items: center; font-size: 32px;
  background: color-mix(in srgb, var(--c) 18%, var(--surface-2)); margin-bottom: 4px;
}
.pick-card h2 { margin: 0; font-size: 24px; }
.pick-card > p { margin: 0; color: var(--muted); font-size: 14px; flex: 1; }
.pick-stats { display: flex; gap: 16px; flex-wrap: wrap; font-size: 13px; color: var(--muted); }
.pick-stats strong { color: var(--text); font-size: 16px; }
.pick-bar { height: 7px; background: var(--surface-2); border-radius: 99px; overflow: hidden; }
.pick-bar span { display: block; height: 100%; background: linear-gradient(90deg, var(--c), var(--c2)); }
.pick-cta { font-weight: 800; color: var(--c); }

/* ============ workbook banner + view ============ */
.workbook-banner {
  display: flex; align-items: center; gap: 16px; margin: 22px 0 4px;
  background: linear-gradient(135deg, color-mix(in srgb, var(--primary) 16%, var(--surface)), var(--surface));
  border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 22px; transition: .16s;
}
.workbook-banner:hover { border-color: var(--primary); transform: translateY(-2px); }
.wb-emoji { font-size: 30px; flex: none; }
.wb-text { display: flex; flex-direction: column; flex: 1; }
.wb-text strong { font-size: 17px; }
.wb-text small { color: var(--muted); font-size: 13px; }
.wb-arrow { font-size: 22px; color: var(--primary); }

.workbook .wb-head { margin-bottom: 18px; }
.wb-body { max-width: 760px; }
.wb-section { margin-bottom: 30px; }
.wb-section-title { display: flex; align-items: center; gap: 12px; font-size: 21px; margin: 0 0 14px; }
.wb-num {
  width: 32px; height: 32px; flex: none; border-radius: 9px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--primary), var(--accent)); color: #fff; font-size: 15px; font-weight: 800;
}
.sub-head { font-size: 17px; margin: 30px 0 12px; color: var(--muted); }

/* ============ backup row ============ */
.backup-row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.backup-hint { font-size: 13px; font-weight: 600; }
.backup-hint.ok { color: var(--good); }
.backup-hint.no { color: var(--danger); }
.cloud-note { color: var(--muted); font-size: 13px; margin: 0 0 6px; }
.cloud-box { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px; }
.cloud-status-line { font-weight: 700; font-size: 14px; margin: 0 0 4px; }
.cloud-hint { color: var(--muted); font-size: 12.5px; margin: 0 0 12px; }
.prog-mod-row.link { text-decoration: none; transition: .14s; border-radius: 10px; padding: 9px 8px; }
.prog-mod-row.link:hover { background: var(--surface-2); }

/* ============ print ============ */
@media print {
  .topbar, .footer, .no-print, .lesson-nav { display: none !important; }
  body { background: #fff; color: #111; }
  .main { max-width: 100%; padding: 0; }
  .wb-body { max-width: 100%; }
  .c-tip, .c-quote, .objectives { border-color: #ccc; background: #f6f6f6; }
  .wb-num, .c-tip-tag { -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  .page-title, .wb-section-title, .c-h { color: #111; }
  .c-p, .c-list li, .wb-text small { color: #222; }
}

/* responsive overrides — kept last so they win over base rules */
@media (max-width: 760px) {
  .course-pick { grid-template-columns: 1fr; }
  .hero-stats { gap: 18px; }
  .pick-card { padding: 24px 22px; }
}