fix nested containers (addresses some of #13682)

docs/examples/carousel/carousel.css

@@ -22,7 +22,7 @@ body {
 }
 
 /* Flip around the padding for proper display in narrow viewports */
-.navbar-wrapper .container {
+.navbar-wrapper > .container {
   padding-right: 0;
   padding-left: 0;
 }
@@ -30,6 +30,9 @@ body {
   padding-right: 15px;
   padding-left: 15px;
 }
+.navbar-wrapper .navbar .container {
+  width: auto;
+}
 
 
 /* CUSTOMIZE THE CAROUSEL
@@ -63,12 +66,6 @@ body {
 /* MARKETING CONTENT
 -------------------------------------------------- */
 
-/* Pad the edges of the mobile views a bit */
-.marketing {
-  padding-right: 15px;
-  padding-left: 15px;
-}
-
 /* Center align the text within the three columns below the carousel */
 .marketing .col-lg-4 {
   margin-bottom: 20px;
@@ -104,12 +101,6 @@ body {
 
 @media (min-width: 768px) {
 
-  /* Remove the edge padding needed for mobile */
-  .marketing {
-    padding-right: 0;
-    padding-left: 0;
-  }
-
   /* Navbar positioning foo */
   .navbar-wrapper {
     margin-top: 20px;

docs/examples/theme/theme.css

@@ -12,3 +12,7 @@ body {
 .theme-showcase > p > .btn {
   margin: 5px 0;
 }
+
+.theme-showcase .navbar .container {
+  width: auto;
+}