index.html

<!DOCTYPE html>
<html>
  <head>
    <link rel="stylesheet" type="text/css" href="style.css" />
  </head>
  <body>
    <div class="main">
      <div id="container1" class="container">
        <div class="item" draggable="true">Item 1</div>
        <div class="item" draggable="true">Item 2</div>
        <div class="item" draggable="true">Item 3</div>
        <div class="item" draggable="true">Item 4</div>
        <div class="item" draggable="true">Item 5</div>
        <div class="item" draggable="true">Item 6</div>
        <div class="item" draggable="true">Item 7</div>
        <div class="item" draggable="true">Item 8</div>
      </div>

      <div id="container2" class="container"></div>
    </div>

    <center><button id="resetBtn">Reset</button></center>

    <script src="script.js"></script>
  </body>
</html>