[html] arranging div one below the other

Try a clear: left on #inner2. Because they are both being set to float it should cause a line return.

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#inner1 {_x000D_
   float:left; _x000D_
}_x000D_
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#inner2{_x000D_
   float:left; _x000D_
   clear: left;_x000D_
}
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<div id="wrapper">_x000D_
    <div id="inner1">This is inner div 1</div>_x000D_
    <div id="inner2">This is inner div 2</div>_x000D_
</div>
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