Try this code, I used the following code for cloning and removing the cloned element, i have also used new class (newClass) which can be added automatically with the newly cloned html
for cloning..
$(".tr_clone_add").live('click', function() {
var $tr = $(this).closest('.tr_clone');
var newClass='newClass';
var $clone = $tr.clone().addClass(newClass);
$clone.find(':text').val('');
$tr.after($clone);
});
for removing the clone element.
$(".tr_clone_remove").live('click', function() { //Once remove button is clicked
$(".newClass:last").remove(); //Remove field html
x--; //Decrement field counter
});
html is as followinng
<tr class="tr_clone">
<!-- <td>1</td>-->
<td><input type="text" class="span12"></td>
<td><input type="text" class="span12"></td>
<td><input type="text" class="span12"></td>
<td><input type="text" class="span12"></td>
<td><input type="text" class="span10" readonly>
<span><a href="javascript:void(0);" class="tr_clone_add" title="Add field"><span><i class="icon-plus-sign"></i></span></a> <a href="javascript:void(0);" class="tr_clone_remove" title="Remove field"><span style="color: #D63939;"><i class="icon-remove-sign"></i></span></a> </span> </td> </tr>