JSFiddle - React, Tailwind, and code Playground

HTML

<div id="drop_zone">Drop files here</div>
<output id="list"></output>

CSS

.thumb {
    height: 75px;
    border: 1px solid #000;
    margin: 10px 5px 0 0;
  }
#drop_zone {
border: 2px dashed #bbb;
-moz-border-radius: 5px;
-webkit-border-radius: 5px;
border-radius: 5px;
padding: 25px;
text-align: center;
font: 20pt bold 'Vollkorn';
color: #bbb;
}

JavaScript

function handleFileSelect(evt) {
    evt.stopPropagation();
    evt.preventDefault();

    var files = evt.dataTransfer.files; // FileList object.

    // files is a FileList of File objects. List some properties.
    var output = [];
    for (var i = 0, f; f = files[i]; i++) 
    {
      // Only process image files.
      if (!f.type.match('image.*')) {
        continue;
      }
      var reader = new FileReader();
      // Closure to capture the file information.
      reader.onload = (function(theFile) 
      {
            return function(e) 
            {
              // Render thumbnail.
              var span = document.createElement('span');
              span.innerHTML = ['<img class="thumb" src="',
                                e.target.result,'" title="',
                                escape(theFile.name),'"/>'].join('');
              document.getElementById('list').insertBefore(span, null);
            };
      })(f);
      // Read in the image file as a data URL.
      reader.readAsDataURL(f);
       
      output.push('<li><strong>', escape(f.name), '</strong> (', f.type || 'n/a', ') - ',
                  f.size, ' bytes, last modified: ',
                  f.lastModifiedDate ? f.lastModifiedDate.toLocaleDateString() : 'n/a',
                  '</li>');
    }
    document.getElementById('list').innerHTML = '<ul>' + output.join('') + '</ul>';
  }

  function handleDragOver(evt) {
    evt.stopPropagation();
    evt.preventDefault();
    evt.dataTransfer.dropEffect = 'copy'; // Explicitly show this is a copy.
  }

  // Setup the dnd listeners.
  var dropZone = document.getElementById('drop_zone');
  dropZone.addEventListener('dragover', handleDragOver, false);
  dropZone.addEventListener('drop', handleFileSelect, false);