JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<div class="row reordered">
  <div class="col-md-12">
    Div1
  </div>
  <div class="col-md-3">
    Div2
  </div>
  <div class="col-md-9">
    Div3
  </div>
</div>

CSS

div{
  border: 2px solid red;
}


@media screen and (max-width: 992px) {
 .reordered {
   display: grid;
 }
  
 .reordered .col-md-3 {
   order: 2;
 }
  
.reordered .col-md-9 {
   order: 1;
 }
}