:root{--kb-bg:#f8fafc;--kb-surface:#fff;--kb-text:#0f172a;--kb-muted:#64748b;--kb-border:#e2e8f0;--kb-brand:#0b74e5}:root[data-theme=dark]{--kb-bg:#0f172a;--kb-surface:#1e293b;--kb-text:#e2e8f0;--kb-muted:#94a3b8;--kb-border:#334155;--kb-brand:#4d94f6}*{box-sizing:border-box}html,body{margin:0;padding:0}body{background:var(--kb-bg);color:var(--kb-text);font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;line-height:1.55}.kb{max-width:960px;margin:0 auto;padding:24px}.kb-head{border-bottom:1px solid var(--kb-border);justify-content:space-between;align-items:center;gap:16px;margin-bottom:24px;padding-bottom:16px;display:flex}.kb-head h1{letter-spacing:-.02em;margin:0;font-size:1.6rem}.kb-muted{color:var(--kb-muted)}.kb-section{margin:28px 0}.kb-section h2{border-bottom:1px solid var(--kb-border);padding-bottom:8px;font-size:1.15rem}.kb-catgroup h3{color:var(--kb-muted);text-transform:uppercase;letter-spacing:.04em;margin:16px 0 6px;font-size:.9rem}.kb-list{margin:0;padding:0;list-style:none}.kb-list li{border-bottom:1px solid var(--kb-border);padding:9px 0}.kb-list a{color:var(--kb-brand);font-weight:500;text-decoration:none}.kb-list a:hover{text-decoration:underline}.kb-videogrid{grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:14px;display:grid}.kb-videocard{background:var(--kb-surface);border:1px solid var(--kb-border);color:var(--kb-text);border-radius:10px;text-decoration:none;transition:transform .1s;overflow:hidden}.kb-videocard:hover{transform:translateY(-2px)}.kb-thumb{aspect-ratio:16/9;color:#fff;background:linear-gradient(135deg,#0b74e5,#0a4aa0);justify-content:center;align-items:center;font-size:.8rem;display:flex}.kb-videotitle{padding:10px;font-size:.9rem;font-weight:500}.kb-btn{background:var(--kb-brand);color:#fff;border-radius:8px;padding:8px 14px;font-size:.9rem;text-decoration:none;display:inline-block}.kb-back{color:var(--kb-muted);margin-bottom:12px;text-decoration:none;display:inline-block}.kb-back:hover{color:var(--kb-brand)}.kb-article{max-width:760px}.kb-article h1{letter-spacing:-.02em;font-size:1.8rem}.kb-lead{color:var(--kb-muted);font-size:1.05rem}.kb-article img{border-radius:8px;max-width:100%}.kb-gate{background:var(--kb-surface);border:1px solid var(--kb-border);text-align:center;border-radius:12px;max-width:480px;margin:60px auto;padding:40px}.kb-player{background:#000;border-radius:12px;position:relative;overflow:hidden}.kb-video{width:100%;display:block}.kb-watermark{color:#ffffff8c;pointer-events:none;text-shadow:0 1px 2px #000c;-webkit-user-select:none;user-select:none;font-size:.8rem;position:absolute;top:10px;right:14px}