JSFiddle - React, Tailwind, and code Playground

HTML

<header>
    <h1>Title</h1>
    <div class="login">Login</div>
</header>

<nav>
    <ul>
        <li><a href="#">Home</a></li>
        <li><a href="#">KAMSC</a></li>
        <li><a href="#">Staff</a></li>
        <li><a href="#">Adminssions</a></li>
        <li><a href="#">Curriculum</a></li>
        <li><a href="#">Sizzling Summer</a></li>
        <li><a href="#">KAMSC Connection</a></li>
        <li><a href="#">Alumni</a></li>
    </ul>
</nav>

CSS

* {
    box-sizing: border-box;
    font-family: sans-serif;
}

header {
    background: teal;
    overflow: hidden;
    padding: 2% 2%;
}

header h1 {
    float: left;
    margin: 0;
    padding: 0;
}

header .login {
    float: right;
}

nav {
    background: lightgray;
    padding: 2% 2%;
}

nav ul {
    font-size: 0;
    margin: 0;
    padding: 0;
    text-align: justify;
}

nav ul:after {
    content: '';
    display: inline-block;
    width: 100%;
}

nav li {
    display: inline-block;
    font-size: 16px;
}