Tweak a few variables.

resources/assets/sass/variables.scss

@@ -24,6 +24,9 @@ $font-size-base: 14px;
 $line-height-base: 1.6;
 $text-color: #636b6f;
 
+// Navbar
+$navbar-default-bg: #fff;
+
 // Buttons
 $btn-default-color: $text-color;
 $btn-font-size: $font-size-base;
@@ -41,3 +44,6 @@ $dropdown-header-color: darken($text-color, 10%);
 $dropdown-link-color: $text-color;
 $dropdown-link-hover-bg: #fff;
 $dropdown-padding: 10px 0;
+
+// Panels
+$panel-default-heading-bg: #fff;