JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="date" id="week-holder" data-bind='foreach: weeksToShow' >
        <li>
            <a href="#" data-bind="css: { selected: week_id == $root.selectedWeek() }, click: $root.changeWeek">
                <p data-bind="text: week_id + '. Week'"></p>
            </a>
        </li>
    </ul>

CSS

.date{
    width: 231px;
    float: left;
    height: 32px;

}
.date li{
    font-family: 'Helvetica Neue', Helvetica, sans-serif;
    list-style: none;
    height: 30px;
    width: 75px;
    float: left;
    border-right: 1px solid #b8b8b8;
    border-top: 1px solid #b8b8b8;
    border-bottom: 1px solid #b8b8b8;
    border-left: 1px solid #b8b8b8;
}

.date li a p{
    font-weight: bold;
    text-decoration: none;
    text-align: center;
    width: 100%;
    height: 30px;
    line-height: 30px;
    font-size: 12px;
    margin-top:0px;
    background-image: -moz-linear-gradient(top, #f3f3f3 0%, #ddddd7 100%); /* FF3.6+ */
    background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#f3f3f3),  color-stop(100%,#ddddd7)); /* Chrome,Safari4+ */
    background-image: -webkit-linear-gradient(top, #f3f3f3 0%,  #ddddd7 100%); /* Chrome10+,Safari5.1+ */
    background-image: -o-linear-gradient(top, #f3f3f3 0%, #ddddd7 100%); /* Opera 11.10+ */
    background-image: -ms-linear-gradient(top,  #f3f3f3 0%,  #ddddd7 100%); /* IE10+ */
    background-image: linear-gradient(to bottom, #f3f3f3 0%,  #ddddd7 100%); /* W3C */
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#f3f3f3', endColorstr='#ddddd7',GradientType=0 ); /* IE6-9 */
    color: #000000;
    text-decoration: none;
}


.date li a:hover p{
    text-decoration: none;
    width: 100%;
    height: 30px;
    line-height: 30px;
    background-image: -moz-linear-gradient(top, #c7c7c7 0%, #d6d6d6 22%, #ddddd7 100%); /* FF3.6+ */
    background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#c7c7c7), color-stop(22%,#d6d6d6), color-stop(100%,#ddddd7)); /* Chrome,Safari4+ */
    background-image: -webkit-linear-gradient(top, #c7c7c7 0%, #d6d6d6 22%, #ddddd7 100%); /* Chrome10+,Safari5.1+ */
    background-image: -o-linear-gradient(top, #c7c7c7 0%, #d6d6d6 22%, #ddddd7 100%); /* Opera 11.10+ */
    background-image: -ms-linear-gradient(top,  #c7c7c7 0%, #d6d6d6...

JavaScript

var FixtureModel = function() {

 var self = this;

    //stores weeks
    self.weeks = ko.observableArray([
            {week_id: "1", week_status:"2"},
            {week_id: "2", week_status:"2"},
            {week_id: "3", week_status:"2"},
            {week_id: "4", week_status:"2"},
            {week_id: "5", week_status:"2"},
            {week_id: "6", week_status:"2"},
            {week_id: "7", week_status:"2"},
            {week_id: "8", week_status:"2"},
            {week_id: "9", week_status:"2"},
            {week_id: "10", week_status:"2"},
            {week_id: "11", week_status:"2"},
            {week_id: "12", week_status:"2"},
            {week_id: "13", week_status:"2"},
            {week_id: "14", week_status:"2"}
    ]);

self.selectedWeek = ko.observable("4");

// Selects 3 weeks to show, depending on the selected week
    self.weeksToShow = ko.computed(function() {
        // Represents a filtered list of weeks
        var desiredWeek = self.selectedWeek();
        return ko.utils.arrayFilter(this.weeks(), function(week) {
            // if first week return first 3 weeks
            if(parseInt(desiredWeek) == 1 && parseInt(week.week_id)<4){
                return week;
            }
            // if last week return last 3 weeks
            if(parseInt(desiredWeek) == 14 && parseInt(week.week_id)>11){
                return week;
            }
            // else return selected week with one before and one after
            if(week.week_id == parseInt(desiredWeek) + 1 | week.week_id == desiredWeek | week.week_id == parseInt(desiredWeek) - 1){
                return week;
            }
        });
    }, this);

    // changes the selected week
    self.changeWeek = function(elem) {
        self.selectedWeek(elem.week_id);
    };
}

ko.applyBindings(new FixtureModel());