JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.microsoft.com/ajax/jquery.ui/1.8.9/themes/start/jquery-ui.css">
<input type='text' id='mydate' />

CSS

.yellow a.ui-state-default {color:black;
                         background-color: yellow ;
                         background: yellow ;}

.green a.ui-state-default {color:black;
                         background-color: green;
                         background: green;}

JavaScript

function severalDates(date){
    var dat = $.datepicker.formatDate("dd.mm.yy", date);
    var r = [true, ""];
    var dates = new Array("8.11.2012", "9.11.2012", "10.11.2012", "11.11.20012", "12.11.2012", "13.11.2012");
    for (var i=0, c=dates.length; i<c; i++) 
        if (dat == dates[i]) 
            r = [true, "yellow"];
    var dates2 = new Array("25.11.2012", "26.11.2012", "27.11.2012", "28.11.20012", "29.11.2012", "30.11.2012");
    for (var i=0, c=dates.length; i<c; i++) 
        if (dat == dates[i]) 
            r = [true, "green"];
        
    return r;
}


$('#mydate').datepicker({beforeShowDay: severalDates});