| 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556 | <!DOCTYPE html><html lang="en"><head>    <meta charset="UTF-8">    <title>Title</title>    <style>        .content {            width: 800px;            height: 600px;            background-color: grey;            margin: 0 auto;            display: flex;        }        .Grid {            display: flex;            height: 100px;            width: 100%;            background-color: #0F769F;        }        .Grid-cell {            flex: 1;            height: 200px;            background-color: saddlebrown;            margin: 5px;        }        .Grid-cell.u-full {            flex: 0 0 100%;        }        .Grid-cell.u-1of2 {            flex: 0 0 50%;        }        /*.Grid-cell.u-1of3 {*/            /*flex: 0 0 33.3333%;*/        /*}*/        .Grid-cell.u-1of4 {            flex: 0 0 25%;        }    </style></head><body><div class="content">    <div class="Grid">        <div class="Grid-cell"></div>        <div class="Grid-cell u-1of4"></div>        <div class="Grid-cell u-1of2"></div>    </div></div></body></html>
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