made header logo only disappear on landing page (#316)

_includes/nav.html

@@ -1,4 +1,14 @@
 {% assign current = page.url | downcase | split: '/' %}
+
+{% if page.url == "/true-index.html" or page.url == "/index.html" or page.url == "/" %}
+<style type="text/css">
+  /* hides the logo in the topleft on the landing page */
+  .navbar-header .navbar-brand{
+    display:none !important;
+  }
+</style>
+{% endif %}
+
 <nav id="header-nav" class="navbar navbar-inverse" role="navigation">
   <div class="container">
       <div class="row">

_sass/layouts/_landing.scss

@@ -1,8 +1,3 @@
-/* hides the logo in the topleft on the landing page */
-.navbar-header .navbar-brand{
-  display:none !important;
-}
-
 .landing {
   .nav-hero-container{
     color:white;