:root{--bg:#f7f8fc;--panel:#fff;--panel2:#f0f3f9;--text:#172033;--muted:#667085;--line:#dfe4ee;--brand:#5b5ce2;--brand2:#7c3aed;--green:#16a66a;--amber:#f59e0b;--red:#dc2626;--shadow:0 18px 50px rgba(34,43,84,.10);--radius:24px}
[data-theme="dark"]{--bg:#0d1220;--panel:#151b2c;--panel2:#1d2539;--text:#edf2ff;--muted:#a9b2c7;--line:#2b354d;--brand:#8b8cf6;--brand2:#a78bfa;--green:#3dd598;--amber:#fbbf24;--red:#fb7185;--shadow:0 18px 50px rgba(0,0,0,.28)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.55}button,input{font:inherit}button{cursor:pointer}a{color:inherit}.app-shell{min-height:100vh}.topbar{position:sticky;top:0;z-index:20;display:flex;align-items:center;gap:18px;padding:12px max(18px,calc((100vw - 1280px)/2));background:color-mix(in srgb,var(--panel) 91%,transparent);backdrop-filter:blur(18px);border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:10px;font-weight:900;letter-spacing:-.03em;white-space:nowrap}.brand-mark{width:38px;height:38px;border-radius:13px;display:grid;place-items:center;color:white;background:linear-gradient(135deg,var(--brand),var(--brand2));box-shadow:0 8px 22px rgba(91,92,226,.28)}.nav{display:flex;gap:4px;flex:1}.nav button,.icon-btn{border:0;background:transparent;color:var(--muted);padding:9px 12px;border-radius:12px;font-weight:750}.nav button:hover,.nav button.active,.icon-btn:hover{background:var(--panel2);color:var(--text)}.stats-mini{display:flex;gap:8px}.stat-pill{display:flex;align-items:center;gap:6px;background:var(--panel2);padding:7px 10px;border-radius:999px;font-size:.86rem;font-weight:800}.main{width:min(1180px,calc(100% - 32px));margin:0 auto;padding:30px 0 76px}.hero{display:grid;grid-template-columns:1.3fr .7fr;gap:22px;align-items:stretch}.hero-card{background:linear-gradient(135deg,#111827,#30347b 55%,#6d3ddb);color:white;border-radius:32px;padding:38px;box-shadow:var(--shadow);position:relative;overflow:hidden}.hero-card:after{content:"";position:absolute;width:260px;height:260px;border-radius:50%;background:rgba(255,255,255,.08);right:-70px;top:-100px}.eyebrow{text-transform:uppercase;letter-spacing:.13em;font-size:.74rem;font-weight:900;opacity:.72}.hero h1{font-size:clamp(2.2rem,5vw,4.2rem);line-height:.98;letter-spacing:-.06em;margin:12px 0 18px}.hero p{font-size:1.05rem;max-width:720px;color:rgba(255,255,255,.78)}.hero-actions{display:flex;gap:10px;flex-wrap:wrap;margin-top:24px}.btn{border:0;border-radius:14px;padding:12px 17px;font-weight:850;display:inline-flex;align-items:center;justify-content:center;gap:8px}.btn-primary{background:var(--brand);color:white;box-shadow:0 10px 25px rgba(91,92,226,.26)}.hero .btn-primary{background:white;color:#25285e}.btn-secondary{background:var(--panel2);color:var(--text)}.btn-danger{background:color-mix(in srgb,var(--red) 15%,var(--panel));color:var(--red)}.btn:disabled{opacity:.45;cursor:not-allowed}.side-card,.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.side-card{padding:26px;display:flex;flex-direction:column;justify-content:space-between}.ring-wrap{display:flex;justify-content:center;margin:10px}.ring{--p:0;width:150px;height:150px;border-radius:50%;display:grid;place-items:center;background:conic-gradient(var(--green) calc(var(--p)*1%),var(--panel2) 0);position:relative}.ring:after{content:"";width:118px;height:118px;background:var(--panel);border-radius:50%;position:absolute}.ring strong{font-size:1.8rem;z-index:1}.ring span{z-index:1;position:absolute;margin-top:42px;font-size:.75rem;color:var(--muted);font-weight:800}.section-head{display:flex;align-items:end;justify-content:space-between;gap:16px;margin:38px 0 16px}.section-head h2{font-size:1.7rem;letter-spacing:-.04em;margin:0}.section-head p{color:var(--muted);margin:4px 0 0}.stage-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.stage-card{position:relative;padding:22px;min-height:260px;display:flex;flex-direction:column;transition:.2s transform,.2s border-color}.stage-card:hover{transform:translateY(-3px);border-color:var(--brand)}.stage-card.locked{filter:saturate(.45);opacity:.72}.stage-top{display:flex;align-items:flex-start;justify-content:space-between}.stage-icon{font-size:2rem;width:54px;height:54px;border-radius:17px;background:var(--panel2);display:grid;place-items:center}.badge{font-size:.72rem;font-weight:900;text-transform:uppercase;letter-spacing:.07em;border-radius:999px;padding:6px 9px;background:var(--panel2);color:var(--muted)}.badge.done{background:color-mix(in srgb,var(--green) 15%,var(--panel));color:var(--green)}.stage-card h3{font-size:1.25rem;line-height:1.15;margin:18px 0 8px;letter-spacing:-.03em}.stage-card p{color:var(--muted);font-size:.9rem;margin:0 0 18px}.stage-meta{display:flex;gap:12px;color:var(--muted);font-size:.82rem;font-weight:750;margin-top:auto}.progress{height:9px;border-radius:99px;background:var(--panel2);overflow:hidden;margin:14px 0}.progress>span{display:block;height:100%;border-radius:inherit;background:linear-gradient(90deg,var(--brand),var(--green));width:0}.stage-link{position:absolute;inset:0;border-radius:inherit}.dashboard-grid{display:grid;grid-template-columns:2fr 1fr;gap:18px}.card{padding:24px}.metric-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}.metric{background:var(--panel2);border-radius:18px;padding:16px}.metric small{display:block;color:var(--muted);font-weight:750}.metric strong{font-size:1.55rem}.timeline{display:flex;flex-direction:column;gap:10px}.timeline-item{display:flex;gap:12px;align-items:center;padding:12px;border-radius:14px;background:var(--panel2)}.timeline-dot{width:11px;height:11px;border-radius:50%;background:var(--brand)}.breadcrumbs{color:var(--muted);font-size:.86rem;font-weight:750;margin-bottom:14px}.breadcrumbs button{border:0;background:none;color:var(--brand);padding:0}.stage-hero{display:grid;grid-template-columns:1fr auto;gap:20px;align-items:center;padding:28px}.stage-hero h1{font-size:2.25rem;letter-spacing:-.05em;margin:5px 0 10px}.stage-hero p{color:var(--muted);max-width:760px}.stage-number{width:110px;height:110px;border-radius:32px;background:linear-gradient(135deg,var(--brand),var(--brand2));color:white;display:grid;place-items:center;font-size:3rem;font-weight:950}.lesson-list{display:flex;flex-direction:column;gap:12px}.lesson-row{display:grid;grid-template-columns:auto 1fr auto;gap:16px;align-items:center;padding:18px;border:1px solid var(--line);background:var(--panel);border-radius:18px}.lesson-index{width:42px;height:42px;border-radius:50%;display:grid;place-items:center;background:var(--panel2);font-weight:900}.lesson-row.complete .lesson-index{background:var(--green);color:white}.lesson-row h3{margin:0 0 4px}.lesson-row p{margin:0;color:var(--muted);font-size:.9rem}.lesson-content{max-width:860px;margin:0 auto}.lesson-content h1{font-size:2.7rem;line-height:1.05;letter-spacing:-.055em}.lesson-content .lead{font-size:1.15rem;color:var(--muted)}.content-section{margin:34px 0}.content-section h2{letter-spacing:-.035em}.content-section p{font-size:1.02rem}.content-section li{margin:8px 0}.code{position:relative;background:#101522;color:#e8eefb;border-radius:18px;padding:20px;overflow:auto;white-space:pre;font:14px/1.55 ui-monospace,SFMono-Regular,Menlo,monospace}.copy-btn{position:absolute;top:10px;right:10px;border:1px solid #3b465e;background:#20283a;color:white;border-radius:9px;padding:6px 9px;font-size:.75rem}.mission{border-left:5px solid var(--amber);background:color-mix(in srgb,var(--amber) 9%,var(--panel));padding:22px;border-radius:0 18px 18px 0;margin:28px 0}.mission.done{border-color:var(--green);background:color-mix(in srgb,var(--green) 9%,var(--panel))}.lesson-nav{display:flex;justify-content:space-between;gap:10px;margin-top:30px}.quiz{max-width:760px;margin:0 auto}.quiz-card{padding:28px}.quiz-count{color:var(--muted);font-weight:800}.quiz-card h2{font-size:1.5rem;letter-spacing:-.03em}.answers{display:grid;gap:10px;margin-top:20px}.answer{border:2px solid var(--line);background:var(--panel);padding:15px;text-align:left;border-radius:15px;color:var(--text);font-weight:750}.answer:hover{border-color:var(--brand)}.answer.selected{border-color:var(--brand);background:color-mix(in srgb,var(--brand) 9%,var(--panel))}.answer.correct{border-color:var(--green);background:color-mix(in srgb,var(--green) 11%,var(--panel))}.answer.wrong{border-color:var(--red);background:color-mix(in srgb,var(--red) 10%,var(--panel))}.feedback{padding:15px;border-radius:14px;background:var(--panel2);margin-top:15px}.result{text-align:center;padding:38px}.result .big{font-size:4.5rem}.settings-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.field{display:flex;flex-direction:column;gap:7px;margin:15px 0}.field label{font-weight:850}.field input{border:1px solid var(--line);background:var(--panel2);color:var(--text);border-radius:12px;padding:12px}.toast{position:fixed;bottom:22px;left:50%;transform:translate(-50%,120px);background:#111827;color:white;padding:12px 18px;border-radius:12px;box-shadow:var(--shadow);z-index:50;transition:.25s}.toast.show{transform:translate(-50%,0)}.empty{text-align:center;padding:50px;color:var(--muted)}.footer{text-align:center;color:var(--muted);padding:20px;font-size:.82rem}.mobile-nav{display:none}.confetti{font-size:2rem;letter-spacing:8px}.skip-link{position:absolute;left:-9999px}.skip-link:focus{left:10px;top:10px;z-index:99;background:white;color:black;padding:10px}
@media(max-width:900px){.hero,.dashboard-grid,.settings-grid{grid-template-columns:1fr}.stage-grid{grid-template-columns:repeat(2,1fr)}.metric-grid{grid-template-columns:repeat(2,1fr)}.stats-mini{display:none}}
@media(max-width:640px){.topbar{padding:10px 14px}.nav{display:none}.main{width:min(100% - 22px,1180px);padding-top:16px;padding-bottom:92px}.hero-card{padding:27px}.stage-grid{grid-template-columns:1fr}.stage-card{min-height:220px}.stage-hero{grid-template-columns:1fr}.stage-number{width:80px;height:80px;border-radius:24px;font-size:2.2rem}.lesson-row{grid-template-columns:auto 1fr}.lesson-row .btn{grid-column:1/-1}.lesson-content h1{font-size:2.1rem}.lesson-nav{flex-direction:column}.mobile-nav{display:grid;grid-template-columns:repeat(4,1fr);position:fixed;z-index:30;bottom:0;left:0;right:0;background:var(--panel);border-top:1px solid var(--line);padding:7px}.mobile-nav button{border:0;background:transparent;color:var(--muted);padding:8px 2px;font-size:.73rem;font-weight:800}.mobile-nav span{display:block;font-size:1.2rem}.metric-grid{grid-template-columns:1fr 1fr}.side-card{min-height:300px}}