*{box-sizing:border-box}body{margin:0;background:#111827;color:#e5e7eb;font:16px system-ui,-apple-system,"Segoe UI",sans-serif}.app{width:min(680px,100%);margin:auto;padding:18px}.preview-card{position:relative;width:100%;aspect-ratio:9/16;max-height:72vh;background:#000;border-radius:14px;overflow:hidden}.preview-card video{width:100%;height:100%;object-fit:cover;background:#000}.preview-card video.front{transform:scaleX(-1)}.empty{position:absolute;inset:0;display:grid;place-items:center;color:#9ca3af}.form{margin-top:16px}label{display:flex;gap:10px;align-items:center}input{flex:1;min-width:0;padding:12px;border:1px solid #374151;border-radius:8px;background:#1f2937;color:#fff;font-size:16px}.buttons{display:grid;grid-template-columns:repeat(2,1fr);gap:10px;margin-top:12px}button{padding:12px;border:0;border-radius:8px;background:#2563eb;color:#fff;font-size:15px}button:disabled{background:#374151;color:#9ca3af}.status{white-space:pre-wrap;margin-top:16px;padding:14px;border-radius:10px;background:#0b1220;color:#b9d7ff;font:13px ui-monospace,SFMono-Regular,Menlo,monospace;line-height:1.6}.hint{color:#9ca3af;font-size:13px;overflow-wrap:anywhere}code{color:#d1d5db}@media(max-width:420px){.app{padding:12px}.buttons{grid-template-columns:1fr}label{align-items:stretch;flex-direction:column;gap:6px}}