JSFiddle - React, Tailwind, and code Playground

HTML

<div class="box"></div>

CSS

.box{
    position:relative;
    background:#fff;
    display:block;
    width:100px; 
    height:100px;  
    border-radius: 100% / 0 0 0 100px;
}

.box::before{
    position:absolute;
    z-index:-1;
    width:100%;
    height:100%;
    background:#f9955e;
    content:"";
}