:root{
  --accent:#2563eb;--bg:#07111f;--panel:#0f172a;--panel2:#162033;--text:#f8fafc;
  --muted:#a9b7ca;--line:rgba(255,255,255,.11);--success:#22c55e;--warning:#f59e0b;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;min-height:100vh;color:var(--text);background:radial-gradient(circle at top right,color-mix(in srgb,var(--accent) 18%,transparent),transparent 30%),var(--bg);font-family:Inter,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif}
button,input,textarea{font:inherit}
button{cursor:pointer}
a{color:inherit}
.app{width:min(1180px,calc(100% - 24px));margin:0 auto;padding:18px 0 42px}
.topbar{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-bottom:14px}.site-language-slot{display:flex;align-items:center;margin-left:auto}
.back{display:inline-flex;align-items:center;gap:7px;text-decoration:none;color:var(--muted)}
.status-pill{padding:7px 10px;border:1px solid var(--line);border-radius:999px;background:rgba(255,255,255,.04);font-size:12px;color:var(--muted)}
.hero{position:relative;overflow:hidden;padding:26px;border:1px solid var(--line);border-radius:24px;background:linear-gradient(135deg,color-mix(in srgb,var(--accent) 22%,#0f172a),#0f172a);box-shadow:0 20px 50px rgba(0,0,0,.24)}
.hero-grid{display:grid;grid-template-columns:1fr auto;gap:18px;align-items:center}
.icon{font-size:72px;filter:drop-shadow(0 12px 25px rgba(0,0,0,.25))}
.eyebrow{display:inline-block;margin-bottom:8px;padding:5px 9px;border-radius:999px;background:rgba(255,255,255,.1);font-size:12px;font-weight:800}
h1{margin:0 0 8px;font-size:clamp(28px,5vw,52px)}
.hero p{max-width:780px;margin:0;color:#d9e4f2;line-height:1.65}
.progress-wrap{margin-top:18px}
.progress-meta{display:flex;justify-content:space-between;gap:10px;margin-bottom:7px;color:#d6e0ec;font-size:12px}
.progress{height:11px;overflow:hidden;border-radius:999px;background:rgba(255,255,255,.12)}
.progress>span{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--accent),#86efac);transition:width .25s}
.nav{display:flex;gap:8px;flex-wrap:wrap;margin:14px 0}
.nav button{padding:10px 13px;border:1px solid var(--line);border-radius:11px;color:var(--muted);background:var(--panel);font-weight:800}
.nav button.active{color:white;border-color:color-mix(in srgb,var(--accent) 65%,white);background:color-mix(in srgb,var(--accent) 26%,var(--panel))}
.section{display:none}
.section.active{display:block}
.grid{display:grid;gap:13px}
.grid.two{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid.three{grid-template-columns:repeat(3,minmax(0,1fr))}
.card{padding:17px;border:1px solid var(--line);border-radius:17px;background:linear-gradient(180deg,var(--panel2),var(--panel));box-shadow:0 14px 34px rgba(0,0,0,.16)}
.card h2,.card h3{margin-top:0}
.card p,.muted{color:var(--muted);line-height:1.6}
.objective{display:flex;gap:10px;align-items:flex-start;padding:10px 0;border-bottom:1px solid var(--line)}
.objective:last-child{border-bottom:0}
.check{display:grid;place-items:center;flex:0 0 27px;width:27px;height:27px;border-radius:50%;background:color-mix(in srgb,var(--accent) 23%,transparent);color:#fff;font-weight:900}
.primary,.secondary,.danger{padding:10px 13px;border:0;border-radius:10px;font-weight:850}
.primary{color:white;background:var(--accent)}
.secondary{color:var(--text);border:1px solid var(--line);background:rgba(255,255,255,.05)}
.danger{color:white;background:#991b1b}
.lesson-actions{display:flex;justify-content:space-between;gap:10px;align-items:center;margin-top:13px}
.lesson-done{color:#86efac;font-size:12px;font-weight:800}
.example{padding:10px;border-left:3px solid var(--accent);border-radius:8px;background:rgba(255,255,255,.035);color:#dbe7f3}
.mission-card{margin-bottom:13px}
.options{display:grid;gap:8px;margin-top:12px}
.option{width:100%;padding:11px 12px;text-align:left;border:1px solid var(--line);border-radius:10px;color:var(--text);background:rgba(255,255,255,.035)}
.option:hover{border-color:var(--accent)}
.option.correct{border-color:#22c55e;background:rgba(34,197,94,.13)}
.option.wrong{border-color:#ef4444;background:rgba(239,68,68,.13)}
.feedback{min-height:22px;margin-top:9px;color:var(--muted);font-size:13px}
.quiz-item{margin-bottom:14px;padding:14px;border:1px solid var(--line);border-radius:13px;background:rgba(255,255,255,.025)}
.quiz-item legend{padding:0 6px;font-weight:800}
.choice{display:block;margin:8px 0;color:var(--muted)}
.choice input{margin-right:7px}
.result{text-align:center;padding:22px}
.score{font-size:56px;font-weight:950;color:var(--accent)}
.badge{display:inline-block;padding:7px 11px;border-radius:999px;background:rgba(34,197,94,.14);color:#86efac;font-weight:900}
textarea{width:100%;min-height:260px;padding:14px;border:1px solid var(--line);border-radius:13px;color:var(--text);background:#0b1422;resize:vertical;outline:none;line-height:1.6}
textarea:focus{border-color:var(--accent)}
.footer-actions{display:flex;gap:9px;flex-wrap:wrap;margin-top:12px}
.certificate{display:none;padding:28px;text-align:center;border:6px double var(--accent);border-radius:20px;background:white;color:#0f172a}
.certificate.show{display:block}
.certificate h2{font-size:34px}
.small{font-size:12px;color:var(--muted)}
.notice{padding:12px 14px;border:1px solid rgba(245,158,11,.35);border-radius:12px;background:rgba(245,158,11,.08);color:#fde68a}
@media(max-width:800px){.grid.two,.grid.three,.hero-grid{grid-template-columns:1fr}.icon{font-size:55px}.app{width:min(100% - 14px,1180px)}.hero{padding:20px}.nav{position:sticky;top:0;z-index:5;padding:8px 0;background:rgba(7,17,31,.94);backdrop-filter:blur(8px)}}
@media print{body{background:white}.topbar,.hero,.nav,.section:not(#certificateSection),.footer-actions,.notice{display:none!important}.certificate{display:block!important}}