JSFiddle - React, Tailwind, and code Playground
HTML
<div class="box" >
<div class="item">
1
</div>
<div class="item">
2
</div>
<div class="item">
3
</div>
</div>
CSS
.box{
display: grid;
grid-template-columns: repeat(3, 1fr);
/* place-items: stretch; */
border-radius: 60px;
position: absolute;
bottom: 0;
/* left: 0; */
justify-items: center;
width: 100%;
z-index: 2;
background-image: linear-gradient(90deg, #191938, #272550,#383263, #3e3368);
top: 2px;
color: #FFF;
/* transform: translate3d(0, 0, -400px); */
}