JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <header class="Header content">
    <h1 class="title"><a href="">LOGO</a></h1>
    <ul class="main_nav">
      <li><a href="">Item 1</a></li>
      <li><a href="">Item 2</a></li>
    </ul>
    <div class="clear"></div>
  </header>
</div>

CSS

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.container {
  float: left;
  width: 100%;
}

.content {
  width: 94%;
  margin: 0 auto;
}

.Header,
.main_nav {
  display: flex;
}

.title {
  flex: 1 0 0;
}

.title a {
  color: green;
  font-size: 0.85em;
}

.main_nav li {
  padding: 0 15px;
}

.main_nav {
  background-color: red;
  justify-content: space-between;
  align-items: center;
}

.main_nav a {
  font-weight: 700;
  font-size: 0.85em;
  color: gray;
}