Color and margin of nav-bar links

Follow up to #43.

- Coloring follows regular links
- Add margin to the left so that page control buttons are visually separated.

Author: timhoffm

mpl_sphinx_theme/static/css/style.css

@@ -21,6 +21,14 @@ html[data-theme="dark"] {
   margin: 2.75rem 0;
 }
 
+#navbar-icon-links {
+    margin-left: 1.5em;
+}
+
 #navbar-icon-links .nav-link {
-  color: #989898;
+  color: var(--pst-color-link);
+}
+
+#navbar-icon-links .nav-link:hover {
+  color: var(--pst-color-link-hover);
 }