fillModeString(default: 'solid')
Controls how the color is applied to the button. Valid values are: "solid", and "none".
Example
<div id="fab-solid"></div>
<div id="fab-none"></div>
<script>
$("#fab-solid").kendoFloatingActionButton({
    icon: "plus",
    fillMode: "solid"
});
$("#fab-none").kendoFloatingActionButton({
    icon: "plus",
    fillMode: "none"
});
</script>In this article