animate not working-JQuery -

am doing wrong simple animate not work?

fiddle

$('#my_btn').click(function(){     alert('clicked');   $("#my_txt").animate({left:'350px'}); }); 

thanks

an element must have position other default static top , left have effect

#my_txt {position: relative; } 

fiddle

preferably have initial left style set well

#my_txt {     position: relative;      left : 0; }