2-column mode table from JSON associative array

2coltableFnction.js

function writeTable(tbody, ark, title) {  
  var td_style = 'padding:5px 10px;border:1px solid black';
  var tble_style = 'border:1px solid black';  
  tbody.empty();  
   $('<tr/>').appendTo(tbody).append('<th colspan="4"><b>'+title+'</b></td>');
    var tr =  $('<tr/>').appendTo(tbody);  
  ark.forEach(function(itm,idx){
    console.log("ITM"+idx+": NN="+itm.nn+" BB="+itm.bb);    
    if (idx % 2 === 0) tr = $('<tr/>').appendTo(tbody);
    tr.append('<td style="'+td_style+'">' + itm.nn + '</td>');
    tr.append('<td style="'+td_style+'">' + itm.bb + '</td>');
  });}

var ark = JSON.parse('[{"nn":"BLU","bb":0},{"nn":"VERDI","bb":-6},{"nn":"NERO","bb":0},{"nn":"VIOLA CALDI","bb":-54},{"nn":"GIALLI","bb":0},{"nn":"GIALLI CALDI","bb":0},{"nn":"GIALLI PRECOCI","bb":-124},{"nn":"GIALLI PRECOCI CALDI","bb":-147},{"nn":"VERDI PRECOCI","bb":-97},{"nn":"ROSSI","bb":0},{"nn":"MINI VERDI","bb":2},{"nn":"DOPPI","bb":-9}]');
writeTable( $('#my-table'), ark, "THIS IS A 4-COLUMN HEADER TITLE")