JSFiddle - React, Tailwind, and code Playground

HTML

<!-- content to be placed inside <body>…</body> -->
<div class="parent">
    <div class="iconspace">
         ¯\_(ツ)_/¯
    </div>
    <div class="rest">
        <ul>
            <li>A</li>
            <li>B</li>
            <li>C</li>
            <li>D</li>
            <li>E</li>
            <li>F</li>
            <li>G</li>
            <li>H</li>
            <li>I</li>
			<li>J</li>
			<li>K</li>
			<li>L</li>
        </ul>
    </div>
</div>


<!--

<div class="parent">
    <div class="iconspace">
         ¯\_(ツ)_/¯
    </div>
    <div class="rest">
        <div class = "ul">
            <div>A</li>
            <li>B</li>
            <li>C</li>
            <li>D</li>
            <li>E</li>
            <li>F</li>
            <li>G</li>
            <li>H</li>
            <li>I</li>
			<li>J</li>
			<li>K</li>
			<li>L</li>
        </div>
    </div>
</div>


-->

CSS

/**
 * Stories Experiment
 */

body {
    background: teal;
}

.parent {
    width: 100%;
    height: 80px;
    background: mistyrose;
    display: flex;
    flex-direction: row;
    justify-content: space-between;
	align-items: center;
	padding: 0 2em;
	border-radius: 50px;
	position: relative;
}

.iconspace {
    width: 100px;
    background: slategray;
    height: 100%;
    display: flex;
	justify-content: center;
	align-items: center;
}

.rest {
    width: calc(100% - 100px);
    height: 100%;
    background: papayawhip;
	overflow-x: auto;
	position: relative;
}

ul {
    display: flex;
    justify-content: space-evenly;
	align-items: center;
	list-style-type: none;
	height: 100%;
	width: 100%;
	margin: 0;
}

li {
	border: 1px solid brown;
    border-radius: 50%;
    min-height: 32px;
    min-width: 32px;
	display: inline-flex;
	justify-content: center;
	align-items: center;
	margin: 0 1em;
	color: crimson;
}