JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
    <form>
        <input type="search">
        <span class="submit"></span>
    </form>
</div>

CSS

#container {
    width: 300px;
    border: 1px solid black;
    height:30px;
    position:relative;
}

input[type="search"] {
    box-sizing:border-box;
    width: 100%;
    border-right:40px solid transparent;
    margin:0;
    padding:0;
    height:30px;
}
.submit {
    position:absolute;
    right:0;
    top:0;
    width: 40px;
    height: 30px;
    background-color: red;
}