JSFiddle - React, Tailwind, and code Playground

HTML

<div id="marquee-container"
     ><span><img src="http://www.dragonfly-site.com/graphics/20-free-dragonfly-clip-art-l.jpg" /></span
     ><span><img src="http://0.tqn.com/d/macs/1/0/2/M/-/-/clipprojectchristmas_400x400.png" /></span
    ></div>

CSS

#marquee-container {
 width: 500px; /* or whatever you want */
 margin: 0 auto; /* centers it */
 overflow: hidden;
 white-space: nowrap;
}

JavaScript

(function(window, document, undefined) {
     var spaceinterval = 1;
     var timeinterval = 10; // `speed`
     var max;
     var firstrun = true;
     // Interval function:
     var gallery = function() {
      var elem = document.getElementById("marquee-container");
      if (elem) {
       if (firstrun) {
        max = elem.scrollWidth;
        // Clone the children of the container until the
        // scrollWidth is at least twice as large as max.
        while (elem.scrollWidth < max * 2) {
         var length = elem.children.length;
         for (var i = 0; i < length; ++i) {
          elem.appendChild(elem.children[i].cloneNode(true));
         }
         break;
        }
        firstrun = false;
       }
       if (elem.scrollLeft >= max) {
        elem.scrollLeft -= max;
       } else {
        elem.scrollLeft += spaceinterval;
       }
      }
     };
     window.setInterval(gallery, timeinterval);
    })(window, document);