:root{
  --bg:#f5f7fb; --surface:#ffffff; --surface-2:#eef3ff; --ink:#172033; --muted:#667085;
  --line:#d9e0ee; --brand:#2459ff; --brand-2:#20b486; --warn:#ffb020; --danger:#e5484d;
  --shadow:0 18px 45px rgba(20,35,70,.10); --radius:22px; --radius-sm:14px; --sidebar:370px;
}
:root.dark{
  --bg:#0d1322; --surface:#131c2e; --surface-2:#18243a; --ink:#f2f5fb; --muted:#aab4c7;
  --line:#2b3956; --brand:#82a2ff; --brand-2:#56d7aa; --warn:#ffd166; --danger:#ff7b7f;
  --shadow:0 18px 45px rgba(0,0,0,.32);
}
*{box-sizing:border-box} html{scroll-behavior:smooth} body{margin:0;background:var(--bg);color:var(--ink);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif;line-height:1.58}
button,input{font:inherit} button{cursor:pointer} a{color:inherit}.app-shell{min-height:100vh}.topbar{position:sticky;top:0;z-index:30;height:76px;display:flex;align-items:center;gap:16px;padding:12px 22px;background:rgba(255,255,255,.82);border-bottom:1px solid var(--line);backdrop-filter:blur(14px)}
.dark .topbar{background:rgba(19,28,46,.84)}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;min-width:0}.brand-mark{display:grid;place-items:center;width:44px;height:44px;border-radius:14px;color:#fff;font-weight:900;background:linear-gradient(135deg,var(--brand),var(--brand-2));box-shadow:0 8px 20px rgba(36,89,255,.25)}.brand small{display:block;color:var(--muted);font-size:12px;margin-top:1px}.topbar-actions{display:flex;gap:10px;margin-left:auto}.icon-button,.ghost,.primary,.secondary,.danger,.text-button{border:0;border-radius:999px;padding:10px 15px;font-weight:800;transition:.18s ease transform,.18s ease background,.18s ease opacity}.icon-button{display:none;background:var(--surface-2);color:var(--ink);width:44px;height:44px}.ghost,.secondary{background:var(--surface-2);color:var(--ink)}.primary{background:var(--brand);color:#fff;box-shadow:0 8px 18px rgba(36,89,255,.25)}.danger{background:rgba(229,72,77,.12);color:var(--danger)}.text-button{background:transparent;color:var(--muted);padding:8px 0}.ghost:hover,.primary:hover,.secondary:hover,.danger:hover,.icon-button:hover{transform:translateY(-1px)}
.primary,.secondary,.ghost{display:inline-flex;align-items:center;justify-content:center;text-decoration:none}

.sidebar{position:fixed;top:76px;left:0;bottom:0;width:var(--sidebar);overflow:auto;padding:20px 18px;background:var(--surface);border-right:1px solid var(--line);z-index:20}.content{margin-left:var(--sidebar);padding:34px;max-width:1220px}.sidebar-card,.search-wrap,.lesson-card,.hero,.panel,.content-card,.quiz-card,.callout,.module-overview{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.sidebar-card{padding:18px;margin-bottom:18px}.eyebrow{text-transform:uppercase;letter-spacing:.12em;font-size:12px;font-weight:900;color:var(--brand);margin:0 0 8px}.progress-ring-wrap{display:flex;align-items:center;gap:14px}.progress-ring{width:78px;height:78px;border-radius:50%;display:grid;place-items:center;background:conic-gradient(var(--brand) 0deg,var(--surface-2) 0deg);font-weight:950}.progress-ring span{display:grid;place-items:center;width:58px;height:58px;border-radius:50%;background:var(--surface)}.progress-ring-wrap small{display:block;color:var(--muted)}.progress-track{height:11px;border-radius:999px;background:var(--surface-2);overflow:hidden;margin-top:16px}.progress-track span{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--brand),var(--brand-2));border-radius:999px}.search-wrap{padding:15px;margin-bottom:18px}.search-wrap label{display:block;font-size:13px;font-weight:850;color:var(--muted);margin-bottom:8px}.search-wrap input{width:100%;border:1px solid var(--line);border-radius:14px;background:var(--bg);color:var(--ink);padding:12px 13px;outline:none}.search-wrap input:focus{border-color:var(--brand);box-shadow:0 0 0 4px rgba(36,89,255,.12)}.module-nav{display:flex;flex-direction:column;gap:12px}.nav-module{border:1px solid var(--line);border-radius:18px;overflow:hidden;background:var(--surface)}.nav-module-header{width:100%;border:0;background:transparent;color:var(--ink);display:flex;align-items:flex-start;gap:10px;padding:13px;text-align:left}.nav-module-header strong{display:block;font-size:14px;line-height:1.25}.nav-module-header small{display:block;color:var(--muted);font-size:12px;margin-top:3px}.module-number{flex:0 0 34px;height:34px;border-radius:12px;display:grid;place-items:center;background:var(--surface-2);font-weight:950;color:var(--brand)}.module-toggle{margin-left:auto;color:var(--muted)}.nav-lessons{display:none;padding:0 10px 10px}.nav-module.open .nav-lessons{display:block}.nav-lesson{display:flex;gap:8px;align-items:flex-start;text-decoration:none;border-radius:12px;padding:9px 8px;color:var(--muted);font-size:13px}.nav-lesson:hover,.nav-lesson.active{background:var(--surface-2);color:var(--ink)}.check-dot{flex:0 0 18px;width:18px;height:18px;border-radius:50%;border:2px solid var(--line);margin-top:1px}.nav-lesson.done .check-dot{border-color:var(--brand-2);background:var(--brand-2);box-shadow:inset 0 0 0 4px var(--surface)}.sidebar-footer{padding:16px 4px 30px}.hero{padding:34px;overflow:hidden;position:relative}.hero:before{content:"";position:absolute;inset:-80px -100px auto auto;width:380px;height:380px;border-radius:50%;background:radial-gradient(circle,rgba(36,89,255,.22),transparent 63%)}.hero-grid{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(280px,.8fr);gap:24px;position:relative}.kicker{display:inline-flex;gap:8px;align-items:center;background:var(--surface-2);color:var(--brand);font-weight:900;border-radius:999px;padding:7px 12px;font-size:13px}.hero h1{font-size:clamp(34px,5vw,62px);line-height:1;margin:18px 0 16px;letter-spacing:-.05em}.hero p{font-size:18px;color:var(--muted);max-width:760px}.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:24px}.stats-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin-top:28px}.stat{padding:16px;border-radius:18px;background:var(--surface-2);border:1px solid var(--line)}.stat strong{display:block;font-size:28px;letter-spacing:-.03em}.stat small{color:var(--muted)}.resume-card{padding:22px;border-radius:var(--radius);background:linear-gradient(135deg,var(--brand),#6837ff);color:#fff;align-self:start;box-shadow:var(--shadow)}.resume-card p{color:rgba(255,255,255,.82);font-size:15px}.resume-card button{background:#fff;color:#172033}.section-title{display:flex;align-items:end;justify-content:space-between;gap:18px;margin:32px 0 14px}.section-title h2{font-size:28px;margin:0;letter-spacing:-.03em}.section-title p{margin:5px 0 0;color:var(--muted)}.module-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.module-overview{padding:20px;display:flex;flex-direction:column;gap:14px}.module-overview h3{margin:0;font-size:20px;letter-spacing:-.02em}.module-overview p{margin:0;color:var(--muted)}.module-meta{display:flex;flex-wrap:wrap;gap:8px}.pill{display:inline-flex;align-items:center;gap:6px;border-radius:999px;background:var(--surface-2);border:1px solid var(--line);padding:6px 10px;color:var(--muted);font-size:12px;font-weight:850}.module-footer{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:auto}.mini-progress{height:8px;background:var(--surface-2);border-radius:999px;overflow:hidden;flex:1}.mini-progress span{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--brand),var(--brand-2))}.lesson-card{padding:30px}.breadcrumb{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:18px;color:var(--muted);font-size:14px}.breadcrumb a{text-decoration:none;color:var(--brand);font-weight:850}.lesson-header{display:flex;align-items:start;justify-content:space-between;gap:20px}.lesson-header h1{font-size:clamp(30px,4vw,48px);line-height:1.05;letter-spacing:-.045em;margin:0 0 12px}.lesson-header p{color:var(--muted);margin:0}.lesson-actions{display:flex;gap:10px;flex-wrap:wrap}.complete-button.done{background:var(--brand-2);color:#052119}.lesson-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:24px;margin-top:24px}.content-card{padding:22px;margin-bottom:16px}.content-card h2,.content-card h3{margin:0 0 12px;letter-spacing:-.02em}.content-card p{margin:0 0 14px}.content-card p:last-child{margin-bottom:0}.numbered-list,.clean-list{padding-left:22px;margin:0}.numbered-list li,.clean-list li{margin-bottom:10px}.side-panel{position:sticky;top:100px;align-self:start}.panel{padding:18px;margin-bottom:16px}.panel h3{margin:0 0 10px}.panel ul{padding-left:18px;margin:0}.panel li{margin-bottom:8px}.quiz-card{padding:18px;margin-bottom:12px}.quiz-card strong{display:block;margin-bottom:8px}.quiz-answer{display:none;color:var(--muted);border-top:1px solid var(--line);margin-top:10px;padding-top:10px}.quiz-card.open .quiz-answer{display:block}.callout{padding:18px;border-left:5px solid var(--brand);background:var(--surface-2);margin:16px 0}.lesson-nav{display:flex;justify-content:space-between;gap:14px;margin-top:22px}.lesson-nav a{flex:1;text-decoration:none}.lesson-nav a:last-child{text-align:right}.footer-note{margin:36px 0;color:var(--muted);font-size:14px;text-align:center}.toast{position:fixed;right:22px;bottom:22px;background:var(--ink);color:var(--surface);border-radius:999px;padding:12px 16px;box-shadow:var(--shadow);opacity:0;transform:translateY(12px);pointer-events:none;transition:.22s ease;z-index:50}.toast.show{opacity:1;transform:translateY(0)}.empty{padding:20px;color:var(--muted);text-align:center}.module-complete-banner{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:18px;border-radius:18px;background:var(--surface-2);border:1px solid var(--line);margin:20px 0}.print-only{display:none}
@media (max-width:1050px){:root{--sidebar:320px}.module-grid{grid-template-columns:1fr}.lesson-layout{grid-template-columns:1fr}.side-panel{position:static}.hero-grid{grid-template-columns:1fr}}
@media (max-width:820px){.icon-button{display:grid;place-items:center}.topbar{padding:10px 14px}.brand small{display:none}.topbar-actions .ghost{display:none}.sidebar{transform:translateX(-105%);transition:.22s ease;width:min(88vw,370px);box-shadow:var(--shadow)}.sidebar.open{transform:translateX(0)}.content{margin-left:0;padding:20px}.hero,.lesson-card{padding:22px}.stats-grid{grid-template-columns:1fr}.lesson-header{flex-direction:column}.lesson-actions{width:100%}.lesson-actions button{flex:1}.module-complete-banner{align-items:flex-start;flex-direction:column}.lesson-nav{flex-direction:column}.lesson-nav a:last-child{text-align:left}}
@media print{.topbar,.sidebar,.lesson-actions,.lesson-nav,.search-wrap,.toast{display:none!important}.content{margin:0;padding:0;max-width:none}.lesson-card,.hero,.content-card,.panel,.quiz-card{box-shadow:none;border-color:#ddd}.app-shell{display:block}body{background:#fff;color:#111}.print-only{display:block}}