:root{--bg:#f6f6f3;--panel:#fff;--text:#171717;--muted:#6b6b6b;--line:#deded8;--brand-primary:#111;--brand-accent:#6d5dfc}*{box-sizing:border-box}html,body{background:var(--bg);color:var(--text);margin:0;padding:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}a{color:inherit}button,input,textarea,select{font:inherit}.shell{max-width:1120px;margin:0 auto;padding:32px 20px 64px}.topbar{justify-content:space-between;align-items:center;gap:20px;padding:8px 0 28px;display:flex}.brand{letter-spacing:-.03em;font-weight:800}.muted{color:var(--muted)}.panel{background:var(--panel);border:1px solid var(--line);padding:24px}.hero{max-width:760px;padding:52px 0 32px}.hero h1{letter-spacing:-.06em;margin:0 0 20px;font-size:clamp(38px,7vw,72px);line-height:.98}.hero p{font-size:19px;line-height:1.6}.grid{grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:14px;display:grid}.card{background:var(--panel);border:1px solid var(--line);padding:22px;text-decoration:none;display:block}.card:hover{border-color:var(--text)}.card h2,.card h3{margin:8px 0}.eyebrow{letter-spacing:.12em;text-transform:uppercase;color:var(--muted);font-size:12px;font-weight:700}.form{gap:12px;max-width:520px;display:grid}.input,.textarea,.select{border:1px solid var(--line);width:100%;color:var(--text);background:#fff;border-radius:0;padding:13px 14px}.button{background:var(--brand-primary);color:#fff;cursor:pointer;border:0;padding:13px 16px;text-decoration:none;display:inline-block}.button.secondary{color:var(--text);border:1px solid var(--line);background:#fff}.auth-wrap{place-items:center;min-height:100vh;padding:24px;display:grid}.auth-card{border:1px solid var(--line);background:#fff;width:min(100%,480px);padding:32px}.auth-card h1{letter-spacing:-.04em;margin:6px 0 12px;font-size:36px}.notice{border:1px solid var(--line);background:#fafafa;padding:14px;line-height:1.5}.course-layout{grid-template-columns:300px 1fr;gap:20px;display:grid}.sidebar{color:#fff;background:#181818;min-height:70vh;padding:26px}.sidebar a{color:#fff;text-decoration:none}.lesson-list{gap:8px;margin-top:20px;display:grid}.lesson-link{border:1px solid #383838;padding:12px;text-decoration:none;display:block}.content{border:1px solid var(--line);background:#fff;min-height:70vh;padding:32px}.content h1{letter-spacing:-.04em;font-size:42px}.content p{font-size:17px;line-height:1.75}.admin-section{border:1px solid var(--line);background:#fff;margin:18px 0;padding:20px}.stack{gap:10px;display:grid}.row{flex-wrap:wrap;align-items:center;gap:10px;display:flex}.tag{border:1px solid var(--line);padding:4px 8px;font-size:12px;display:inline-block}.danger{color:#a40000}@media (max-width:780px){.course-layout{grid-template-columns:1fr}.sidebar{min-height:auto}.content h1{font-size:34px}.topbar{align-items:flex-start}.hero{padding-top:28px}}