<div class='row'>

    <div id='cell0' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)" ></div>
    <div id='cell1' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>
    <div id='cell2' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>
    <div id='cell3' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>
    <div id='cell4' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>
    <div id='cell5' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>
    <div id='cell6' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>
    <div id='cell7' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>
    <div id='cell8' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>
    <div id='cell9' class='cell' ondrop="drop(event)" ondragover="allowDrop(event)"></div>

</div>

function allowDrop(ev) {
ev.preventDefault();}
     window.allowDrop = function(ev) {
ev.preventDefault();
if (ev.target.getAttribute("draggable") == "true")
    ev.dataTransfer.dropEffect = "none"; // dropping is not allowed

else
    ev.dataTransfer.dropEffect = "all"; // drop it like it's hot};