Docs: Fix iframe width on homepage

Ref https://github.com/qunitjs/jekyll-theme-amethyst/commits/v2.10.1/

Author: Krinkle

docs/Gemfile

@@ -2,4 +2,4 @@ source "https://rubygems.org"
 ruby RUBY_VERSION
 
 # To apply changes, run `bundle update`.
-gem "jekyll-theme-amethyst", "2.10.0", group: :jekyll_plugins
+gem "jekyll-theme-amethyst", "2.10.1", group: :jekyll_plugins

docs/_sass/custom.scss

@@ -51,11 +51,6 @@ h3 a {
   height: auto;
 }
 
-.main iframe {
-  width: revert-layer;
-  max-width: 100%;
-}
-
 .content figure {
   margin: $size-spacing 0;
   text-align: center;
@@ -116,6 +111,18 @@ h3 a {
   text-decoration: none;
 }
 
+/* Home */
+
+.example-result iframe {
+    width: 100%;
+    border-radius: 3px;
+}
+
+.example-result iframe,
+.example-result pre {
+    height: 360px;
+}
+
 /* Browser */
 
 // Discourage selecting to copy/paste because this demonstrates