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How do I disable form fields using CSS?
<input type="text" name="username" value="admin" >
<style type="text/css">
  input[name=username] {
    disabled: true; /* Does not work */
  }
</style>

<div style="position:relative">
<div id="first" style="position:absolute;top:0px;left:0px;width:400px;height:200px;background-color:red;">
<input type="text" style="background-color:gray" tabindex="-1" />
</div>
<div id="second" style="position:absolute;top:0px;left:0px;width:400px;height:200px;"></div>
</div>

$('#fieldId').attr('disabled', 'disabled'); //Disable
$('#fieldId').attr('disabled', ''); //Enable

disabled="disabled"