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codice:
<section class="container-fluid">
<div class="row d-flex flex-row flex-nowrap">
<div class="col-8 m-1">A</div>
<div class="col-4 m-1">B</div>
</div>
<div class="row d-flex flex-row flex-nowrap">
<div class="col-8 m-1">C</div>
<div class="col-4 m-1">D</div>
</div>
</section>