:root{--bg: #f8f9fb;--surface: #ffffff;--surface-alt: #f3f4f7;--text: #16181d;--muted: #16181d;--border: #d8dde7;--accent: #1f5eff;--accent-soft: rgba(31, 94, 255, .12);--shadow: 0 6px 24px rgba(20, 24, 32, .06)}*{box-sizing:border-box}html,body,#root{margin:0;min-height:100%;font-family:Inter,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:var(--bg);color:var(--text)}body{line-height:1.5}button,input{font:inherit}a{color:var(--text);text-decoration:none}a.active{color:var(--accent);font-weight:600}.app-shell{min-height:100vh}.topbar{display:flex;justify-content:space-between;align-items:center;padding:18px 28px;border-bottom:1px solid var(--border);background:var(--surface)}.brand-title{font-size:1.1rem;font-weight:800}.brand-subtitle{font-size:.92rem;color:var(--muted)}.nav{display:flex;gap:18px}.page-wrap{max-width:1280px;margin:0 auto;padding:24px}.panel{background:var(--surface);border:1px solid var(--border);border-radius:18px;padding:18px;box-shadow:var(--shadow)}.hero{width:min(100%,950px);margin:0 auto}.hero-text{max-width:62ch;color:var(--muted)}.dashboard-page{display:grid;gap:20px}.dashboard-section{padding:24px}.dashboard-heading{margin-bottom:8px}.dashboard-intro{margin-top:0;color:var(--muted);max-width:65ch}.preferences-grid{display:grid;grid-template-columns:repeat(2,minmax(220px,1fr));gap:14px;margin-top:16px}.topic-choice-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;margin-top:16px}.topic-choice-button{min-height:64px;border:1px solid var(--border);border-radius:16px;background:var(--surface-alt);color:var(--text);font-weight:600;padding:14px 16px;text-align:center;cursor:pointer}.topic-choice-button.active{border-color:var(--accent);background:var(--accent-soft);color:var(--accent)}.content-title{margin-bottom:6px}.content-subtitle{margin-top:0}.topic-content-stack{display:grid;gap:18px;margin-top:18px}.topic-content-block 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var(--border);border-radius:14px;background:var(--surface-alt)}.info-line{color:var(--muted);margin-top:4px}.visual-block{margin:18px 0}.visual-placeholder{height:180px;border:2px dashed var(--border);border-radius:16px;display:grid;place-items:center;background:var(--surface-alt);color:var(--muted)}.visual-image{width:100%;max-height:260px;object-fit:contain;border-radius:16px;border:1px solid var(--border)}.visual-caption{margin-top:10px}.steps-list{padding-left:20px}.details-box{margin-top:14px;padding:12px;border:1px solid var(--border);border-radius:12px;background:var(--surface-alt)}.details-body{margin-top:10px}.related-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:12px}.topic-card{border:1px solid var(--border);border-radius:16px;padding:14px;background:var(--surface-alt);text-align:left;width:100%}.topic-card.selected{border-color:var(--accent);background:var(--accent-soft)}.topic-card-title{font-weight:700;margin-bottom:8px}.topic-card-text{color:var(--muted);font-size:.95rem}h1,h2,h3,p{margin-top:0}@media(max-width:980px){.dashboard-layout{grid-template-columns:1fr}.sidebar{position:static}}@media(max-width:640px){.topbar{padding:16px;flex-direction:column;align-items:start;gap:10px}.page-wrap{padding:16px}}.familiar-section{padding:24px}.section-intro{color:var(--muted);max-width:65ch;margin-bottom:18px}.piece-card-list{display:grid;gap:14px}.piece-card{border:1px solid var(--border);border-radius:16px;background:var(--surface-alt);overflow:hidden}.piece-card summary{list-style:none}.piece-card 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