How get the base URL via context path in JSF?

I have this structure:

WebContent
    resources
        components
            top.xhtml

    company
        about_us.xhtml

    index.xhtml

top.xhtml is a component, that is used in index.xthml and about_us.xhtml too.

top.xhtml

<ul>
    <li><a href="index.xhtml">Home</a></li>
    <li><a href="company/about_us.xhtml">About us</a></li>
    ...
</ul>

So my problem is, when the current page is index.xhtml the component generates URLs correctly, but when the current page is about_us.xhtml, it generates wrong URLs. I cannot use relative path because it's going to generate the wrong URL too. I think it is because the component is based on the current path of the *.xhtml page.

The only solution I could found out is:

<ul>
    <li><a href="${pageContext.request.contextPath}/webname/index.xhtml">Home</a></li>
    <li><a href="${pageContext.request.contextPath}/webname/about_us.xhtml">About us</a></li>
    ...
</ul>

But I think is not 'elegant' at all. Any ideas?