private void WriteOpening()
{
var navAttrs = new HtmlAttributes(new { @class = "nav" });
if (_settings.Style == NavStyle.Navbar) navAttrs["class"] += "navbar-nav";
else navAttrs["class"] += "nav-" + _settings.Style.ToString().ToLower();
if (_settings.Stacked) navAttrs["class"] += "nav-stacked";
if (_settings.Justified) navAttrs["class"] += "nav-justified";
if (_settings.NavbarRight) navAttrs["class"] += "navbar-right";
Write("<ul {0}>", navAttrs.ToString());
}