<div class="panel panel-primary">
    <div class="panel-body">
        <button type="button" class="play btn" ng-class="{'btn-success': !isPlay, 'btn-danger': isPlay}" ng-click="play()">
            {{ isPlay ? 'Stop' : 'Play' }}
        </button>
    </div>
</div>

<!-- Modal -->
<div id="modalGame" class="modal fade" role="dialog">
    <div class="modal-dialog modal-lg">
        <div class="modal-content">
            <div class="modal-header">
                <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
                <h4 class="modal-title" id="myModalLabel">Game Play</h4>
            </div>
            <div class="modal-body">
                <div id="gameviewplay"></div>
            </div>
        </div>
    </div>
</div>

<div class="panel panel-primary">
    <div class="panel-body">
        <button type="button" class="play btn" ng-class="{'btn-success': !isPlay, 'btn-danger': isPlay}" ng-click="play()">
            {{ isPlay ? 'Stop' : 'Play' }} <ng-md-icon icon="{{ isPlay ? 'stop' : 'play_arrow'}}" />
        </button>
    </div>
</div>

<!-- Modal -->
<div id="modalGame" class="modal fade" role="dialog">
    <div class="modal-dialog modal-lg">
        <div class="modal-content">
            <div class="modal-header">
                <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
                <h4 class="modal-title" id="myModalLabel">Game Play</h4>
            </div>
            <div class="modal-body">
                <div id="gameviewplay"></div>
            </div>
        </div>
    </div>
</div>

Add icone no botao de play e stop
Add icone no botao de play e stop
