Via CSS:
One solution is to set the same style for disabled and enabled buttons using the button[disabled]
css selector like this:
button[disabled], button{
color:#fff;
border: none;
background-color: grey;
}
The problem is that browsers have different styles for buttons by default, so you will need to style your buttons.
Via Jquery:
Another solution is to remove the click event handler to the buttons, so replace this line:
$("button").attr("disabled", "disabled");
for this one:
$('button').off('click');
To enable the click event again use:
$('button').on('click');
More info about add/remove events handler on this good answer at SO
Note: You should add id for the buttons (if you are using more than one) because the code above will remove the click on all your buttons.