drawMarginGuides(pageInfo: PageInfo, targetCanvas: HTMLCanvasElement, scale: number): void {
    if (this.disposed) return;
    const surface = this.makeSurface(targetCanvas);
    const canvas = surface.getCanvas();
    const paint = this.makeStrokePaint('#c0c0c0', 0.3);
    const left = pageInfo.marginLeft;
    const top = pageInfo.marginHeader + pageInfo.marginTop;
    const right = pageInfo.width - pageInfo.marginRight;
    const bottom = pageInfo.height - pageInfo.marginFooter - pageInfo.marginBottom;
    const length = 15;

    try {
      canvas.save();
      canvas.scale(scale, scale);
      canvas.drawLine(left, top - length, left, top, paint);
      canvas.drawLine(left, top, left - length, top, paint);
      canvas.drawLine(right + length, top, right, top, paint);
      canvas.drawLine(right, top, right, top - length, paint);
      canvas.drawLine(left - length, bottom, left, bottom, paint);
      canvas.drawLine(left, bottom, left, bottom + length, paint);
      canvas.drawLine(right, bottom + length, right, bottom, paint);
      canvas.drawLine(right, bottom, right + length, bottom, paint);
      canvas.restore();
      surface.flush();
    } finally {
      paint.delete?.();
      surface.delete?.();
    }
  }

  private makeSurface(targetCanvas: HTMLCanvasElement): SkSurface {
    if (this.surfaceRequest.preference === 'software' && typeof this.canvasKit.MakeSWCanvasSurface === 'function') {
      const swSurface = this.canvasKit.MakeSWCanvasSurface(targetCanvas);
      if (swSurface) return swSurface;
    }
    const surface = this.canvasKit.MakeCanvasSurface(targetCanvas)
      ?? this.canvasKit.MakeSWCanvasSurface?.(targetCanvas);
    if (!surface) {
      throw new Error('CanvasKit surface를 만들 수 없습니다');
    }
    return surface;
  }

  private imageForOp(op: LayerImageOp): any | null {
    const key = op.base64 ? `${op.mime ?? 'application/octet-stream'}:${op.base64}` : null;
    if (!key) return null;
    const cached = this.imageCache.get(key);
    if (cached) return cached;
    const bytes = base64ToBytes(op.base64 ?? '');
    const image = this.canvasKit.MakeImageFromEncoded(bytes);
    if (!image) return null;
    this.imageCache.set(key, image);
    this.asyncResourceReady?.();
    return image;
  }

function parseCssColor(value: string): { r: number; g: number; b: number; a: number } {
  const trimmed = value.trim();
  const hex = /^#?([0-9a-f]{6})$/i.exec(trimmed);
  if (hex) {
    const n = Number.parseInt(hex[1], 16);
    return {
      r: (n >> 16) & 0xff,
      g: (n >> 8) & 0xff,
      b: n & 0xff,
      a: 1,
    };
  }
  const rgb = /^rgba?\((\d+),\s*(\d+),\s*(\d+)(?:,\s*([0-9.]+))?\)$/i.exec(trimmed);
  if (rgb) {
    return {
      r: Number(rgb[1]),
      g: Number(rgb[2]),
      b: Number(rgb[3]),
      a: rgb[4] === undefined ? 1 : Number(rgb[4]),
    };
  }
  return { r: 0, g: 0, b: 0, a: 1 };
}

  private renderTextRun(canvas: SkCanvas, op: LayerTextRunOp): void {
    if (!op.text) return;
    const style = op.style ?? {};
    const paint = this.makeFillPaint(style.color ?? '#000000');
    paint.setAntiAlias?.(true);
    const fontSize = style.fontSize ?? Math.max(1, op.bbox.height || 12);
    const font = new this.canvasKit.Font(null, fontSize);
    const x = op.bbox.x;
    const y = op.baseline ?? op.bbox.y + fontSize;
    canvas.save();
    if ((op.rotation ?? 0) !== 0) {
      canvas.rotate(op.rotation, x, y);
    }
    canvas.drawText(op.text, x, y, paint, font);
    canvas.restore();
    font.delete?.();
    paint.delete?.();
  }

  private renderPath(canvas: SkCanvas, op: LayerPathOp): void {
    const path = new this.canvasKit.Path();
    let currentX = op.bbox.x;
    let currentY = op.bbox.y;
    for (const command of op.commands ?? []) {
      [currentX, currentY] = this.applyPathCommand(path, command, currentX, currentY);
    }
    const style = op.style ?? {
      strokeColor: op.lineStyle?.color,
      strokeWidth: op.lineStyle?.width,
      fillColor: null,
    };
    this.drawStyledPath(canvas, path, style);
    path.delete?.();
  }

  private imageForOp(op: LayerImageOp): any | null {
    const key = op.base64 ? `${op.mime ?? 'application/octet-stream'}:${op.base64}` : null;
    if (!key) return null;
    const cached = this.imageCache.get(key);
    if (cached) return cached;
    const bytes = base64ToBytes(op.base64 ?? '');
    const image = this.canvasKit.MakeImageFromEncoded(bytes);
    if (!image) return null;
    this.imageCache.set(key, image);
    this.asyncResourceReady?.();
    return image;
  }

  getPageLayerTreeObject(pageNum: number, profile: LayerRenderProfile = 'screen'): PageLayerTree {
    if (!this.doc) throw new Error('문서가 로드되지 않았습니다');
    const d = this.doc as unknown as {
      getPageLayerTreeWithProfile?: (p: number, profile: string) => string;
      getPageLayerTree?: (p: number) => string;
    };
    const json = typeof d.getPageLayerTreeWithProfile === 'function'
      ? d.getPageLayerTreeWithProfile(pageNum, profile)
      : this.getPageLayerTree(pageNum);
    const tree = JSON.parse(json) as PageLayerTree;
    if (!tree.profile) {
      tree.profile = profile;
    }
    return tree;
  }