<div>
  <h1>Only accepts JPG and PNG.</h1>
  <input type="file" id="file-uploader" accept=".jpg, .png" multiple>
  <p>Multiple files.</p>
  <p id="feedback"></p>
</div>

html {
  height: 100%;
}

body {
  background: white;
  color: black;
}

div {
  display: flex;
  justify-content: center;
  flex-direction: column;
  align-items: center;
  font-family: 'Roboto Mono', monospace;
}

const fileUploader = document.getElementById('file-uploader');

fileUploader.addEventListener('change', (event) => {
  const files = event.target.files;
  console.log('files', files);
  
  // show the upload feedback
  const feedback = document.getElementById('feedback');
  const msg = `${files.length} file(s) uploaded successfully!`;
            feedback.innerHTML = msg;
});