JSFiddle - React, Tailwind, and code Playground
by Jitendra Pal
HTML
<div id="header"> Fab </div>
<div id="main-container">
<div class="item">Item1
<div id="item1-container">
<div class="sub-item">Inside Item1</div>
<div class="sub-item">Inside Item2</div>
<div class="sub-item">Inside Item3</div>
</div>
</div>
<div class="item">Item2</div>
<div class="item">Item3</div>
<div class="item">Item4</div>
</div>
CSS
#header{
height:80px;
font-size:50px;
}
#main-container{
background-color:grey;
display: flex;
flex-direction:column;
padding:2px;
height:calc(100vh - 100px);
}
.item{
background-color:pink;
margin:10px;
height:200px;
}
#item1-container{
display:column;
flex-direction:row;
justify-content: space-around;
}
.sub-item{
background-color:green;
margin:5px;
}