<!-- chage the position of the button and name with classToggle -->
<div id="panel1" class="p1">
<input type="button" value="add" id="btn1" />
<br>
<input type="button" value="add" id="btn2" />
<br>
<input type="button" value="add" id="btn3" />
</div>
<div class="p2"></div>