This code sample demonstrates how to create a data source using an iframe element and then flow that data into a CSS Region container to be distributed over the elements in that container.
// CSS
.content-source {
-ms-flow-into: content;
}
.s1-region {
-ms-flow-from: content;
width: 300px;
height: 150px;
border: 1px solid #ccc;
}
// HTML
<iframe class="content-source" src="content.html"></iframe>
<div class="s1-region"></div>
<div class="s1-region"></div>
<div class="s1-region"></div>