Focus in on prepended inputs

Question

I am prepending inputs on a dom element div as shown below:

<div class="parentDiv">
  <div onClick="addInputs()">Add inputs</div>
  <div id="inputsContainer"></div>
</div>
<!-- hardcoded inputs -->
<input type="text">

function addInputs() {
  $("#inputsContainer").prepend("<input type='text'>");
}

$("input").focusin(function(){
  $(this).css("background-color", "#FFFFCC");
});

This focusin works on hardcoded inputs, but does not trigger on prepended inputs. Let me know where I am going wrong.