boostrap grid
<!- BOOTSTRAP GRID SYSTEM ------------------------>
Extra small .col- <576px Mobile Display
Small .col-sm- ≥576px Mobile Display
Medium .col-md- ≥768px Tablet Display
Large .col-lg- ≥992px Desktop Display
Extra large .col-xl- ≥1200px Desktop Display
<div class="row">
<div class="col-lg-3 col-md-4 col-sm-6" style="background-color:red; border:1px solid black;">
One of four columns
</div>
<div class="col-lg-3 col-md-4 col-sm-6" style="background-color:yellow; border:1px solid black;">
One of four columns
</div>
<div class="col-lg-3 col-md-4 col-sm-6" style="background-color:green; border:1px solid black;">
One of four columns
</div>
<div class="col-lg-3 col-md-4 col-sm-6" style="border:1px solid black;">
One of four columns
</div>
</div>