如何使用html、css、js突出显示任何图像中给定的文本并保存相同的图像？

<div id="imageContainer">
  <img src="image.jpg" alt="Image">
  <span id="textOverlay">Text Overlay</span>
</div>

#imageContainer {
  position: relative;
}

#textOverlay {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  opacity: 0.8;
  font-size: 24px;
  color: white;
}

// 获取图像和文本元素
var image = document.querySelector('#imageContainer img');
var text = document.querySelector('#textOverlay');

// 创建Canvas元素
var canvas = document.createElement('canvas');
canvas.width = image.width;
canvas.height = image.height;

// 获取Canvas上下文
var context = canvas.getContext('2d');

// 绘制图像
context.drawImage(image, 0, 0);

// 设置文本样式
context.font = '24px Arial';
context.fillStyle = 'white';
context.textAlign = 'center';
context.textBaseline = 'middle';

// 绘制文本
context.fillText(text.textContent, canvas.width / 2, canvas.height / 2);

// 将Canvas转换为图像URL
var imageURL = canvas.toDataURL();

// 创建下载链接
var downloadLink = document.createElement('a');
downloadLink.href = imageURL;
downloadLink.download = 'image_with_text.png';
downloadLink.innerHTML = 'Download Image';

// 将下载链接添加到页面
document.body.appendChild(downloadLink);