FSS Columns - Mixed-width columns, two sidebars

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    <div class="fl-fix">
        <h3>Mixed-width columns, two sidebars</h3>
        <p>Two fixed-width columns, forced to left and right; one flexible-width colum in the middle.</p>
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    <div class="fl-col-mixed-100">
        <div class="fl-col-fixed fl-force-left">This is the first column, forced left.<br/>
          Aliquam erat volutpat. Aliquam consequat, quam at varius tincidunt,
          nunc augue blandit sem.</div>
        <div class="fl-col-fixed fl-force-right">This is the second column, forced right.
          <br/>Aenean urna erat, accumsan vel porttitor vitae, blandit a magna.</div>
        <div class="fl-col-flex">This is the third column, the flexible one.<br/>
          It is listed after the forced-alignment columns. Suspendisse vehicula quam
          sit amet mi venenatis quis suscipit massa porttitor.</div>
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    <div class="fl-push">Footer</div>
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