JSFiddle - React, Tailwind, and code Playground

HTML

<header>
    <div class='logo'></div>
    <div class='appName'><h3>Some App</h3></div>
    <div class='btn-container'>
        <button >Help</button>
        <button>Logout</button>
    </div>
</header>

CSS

header {
    position: fixed;
    top: 0px;
    width: 100%;
    display: table;
}
header div {
    display: table-cell;
    vertical-align: middle;
}
.logo {
    width:40px;
    background: steelblue;
    height: 40px;
    float: left;
}
.btn-container {
    width: 80px;
    float: right;
}
.appName {
    text-align: center;
    width: 100%;
}