<div style="z-index: 99999; position: fixed; top: 0">
    <div class="visible-sm">
        visible XS
    </div>
    <div class="visible-sm">
        visible SM
    </div>
    <div class="visible-md">
        visible MD
    </div>
    <div class="visible-lg">
        visible LG
    </div>
</div>