jquery - How can i place a button always center of the graph -

enter image description herei have 1 start button.how can place start button center of graph when resize window should center of graph.how can it?

js:

  $( window ).resize(function() {      var chart = $('#container').highcharts();       var textx = chart.plotleft + (chart.plotwidth  * 0.5);      var texty = chart.plottop  + (chart.plotheight * 0.5);       $('. placebtn').css('left', textx + (span.width() * -0.5));      $('. placebtn').css('top', texty + (span.height() * -0.5));   });        var chart = $('#container').highcharts();       var textx = chart.plotleft + (chart.plotwidth  * 0.5);      var texty = chart.plottop  + (chart.plotheight * 0.5);       $('. placebtn').css('left', textx + (span.width() * -0.5));      $('. placebtn').css('top', texty + (span.height() * -0.5)); 

jsfiddle:https://jsfiddle.net/7skvx8l5/2/

remove position: absolute, , add text-align: center row.

.placebtn {     /* position: absolute; */     width:94px;     background-color:#ccc !important;     border-color: #000 !important;     color: #000000; }  .col-lg-12 {   text-align: center; } 

working example

if don't calling text-align every .col-lg-12, can add class row this:

<div class='col-lg-12 center'> 

and in stylesheet:

.center {     text-align: center; } 

or mean this:

working example