Adjusting the navbar

This design calls for a fixed top navbar with a significant color shift for hovered and active links. I've already applied some of these styles by setting appropriate variables. Let me point those out, and then we'll move on to make some necessary adjustments to the markup.

The less/_variables.less file is based on Bootstrap's variables.less file. I've customized the shades of gray as per previous projects. You'll see these in the topmost section of the file.

I've further adjusted the following navbar variables, adjusting its height, margin, colors, and hover colors specifically for this design:

// Basics of a navbar
@navbar-height:                    56px;
@navbar-margin-bottom:             0;
...
// Navbar links
@navbar-default-link-color:       @navbar-default-color;
@navbar-default-link-hover-color: #fff;
@navbar-default-link-hover-bg:    @gray;
@navbar-default-link-active-color: #fff;
@navbar-default-link-active-bg:  @gray-dark;

In addition, I've adjusted the variables...