<div class="row">
    <div class="col-md-8">
        <h3 class="heading_a"><span class="heading_text">Combination Chart</span></h3>
        <div id="c3_combined" style="height:280px"></div>
    </div>
    <div class="col-md-4">
        <h3 class="heading_a"><span class="heading_text">Gauge Chart</span></h3>
        <div id="c3_gauge" style="height:280px"></div>
    </div>
</div>
<div class="row">
    <div class="col-md-4">
        <h3 class="heading_a"><span class="heading_text">Donut Chart</span></h3>
        <div id="c3_donut" style="height:280px"></div>
    </div>
    <div class="col-md-8">
        <h3 class="heading_a"><span class="heading_text">Grid Lines</span></h3>
        <div id="c3_grid_lines" style="height:280px"></div>
    </div>
</div>
 <div class="row">
    <div class="col-md-12">
        <h3 class="heading_a"><span class="heading_text">Scatter Plot</span></h3>
        <div id="c3_scatter" style="height:280px"></div>
    </div>
</div>