<header class="site-header">
    <div class="wrapper">
        <a class="site-title" href="{{ site.baseurl }}/">{{ site.title }}</a>
        <nav class="site-nav">
            <a href="{{ site.baseurl }}/">Home</a>
            <a href="{{ site.baseurl }}/releases/{{site.sinon.current_release}}">API Documentation</a>
            <a href="{{ site.baseurl }}/releases">Releases</a>
            <a href="{{ site.baseurl }}/how-to">How To</a>
        </nav>
    </div>
</header>

<header class="site-header">
    <div class="wrapper">
        <a class="site-title" href="{{ site.baseurl }}/">{{ site.title }}</a>
        <nav class="site-nav">
            <a class="page-link" href="{{ site.baseurl }}/">Home</a>
            <a class="page-link" href="{{ site.baseurl }}/releases/{{site.sinon.current_release}}">API Documentation</a>
            <a class="page-link" href="{{ site.baseurl }}/releases">Releases</a>
            <a class="page-link" href="{{ site.baseurl }}/how-to">How To</a>
        </nav>
    </div>
</header>

Add more space between navbar page links
Add more space between navbar page links
