html到pdf在jsPDF javascript中不同

我有一个html页面，通过点击按钮转换为PDF， 但下载时却不一样， 如何在jspdf javascript中设置宽度和高度匹配

当检查器打开/屏幕调整大小时，pdf宽度高度不适合屏幕

convertPDF = () => {
  html2canvas(document.querySelector("#content")).then(canvas => {
     var imgData = canvas.toDataURL("image/png",1);
     var pdf = new jsPDF("p", "pt", "letter");
     var pageWidth = pdf.internal.pageSize.getWidth();
     var pageHeight = pdf.internal.pageSize.getHeight();
     var imageWidth = canvas.width;
     var imageHeight = canvas.height;
     var ratio = imageWidth/imageHeight >= pageWidth/pageHeight ? pageWidth/imageWidth : pageHeight/imageHeight;
     pdf.addImage(imgData, 'JPEG', 0, 0, imageWidth*ratio, imageHeight*ratio);
     pdf.save("sample.pdf");
  });
}