<div class="containerContent extension-nofooter">
    <div class="extension-position-middle">
        <img class="extension-image-center" data-ng-src="warning.jpg" />
        <h2 class="extension-center">Message Title</h2>
        <div class="extension-center" > description text and this can go very big</div>
    </div>
</div>

.extension-nofooter{
    bottom:1em;
}
.extension-center{
    text-align:center;
    margin:0.2em;
}
.extension-image-center {
    display: block;
    margin-top: 1em;
    margin-bottom: 1em;
    margin-left: auto;
    margin-right: auto;
    max-width:90%;
}
.extension-position-middle {
    text-align: center;
    vertical-align: middle;
    margin-left:2em;
    margin-right:2em;
}