style(docs): improve styling of code blocks

Author: camerondubas

tests/dummy/app/styles/app.scss

@@ -201,6 +201,16 @@ th, td {
   color: #bbb;
 }
 
+pre > code {
+  border: none;
+  margin: 0;
+  padding: 0 .5rem;
+}
+
+:not(pre) > code[class*="language-"], pre[class*="language-"] {
+  background-color: #f8f8f8;
+}
+
 .code-template-toggle {
   position: relative;
   background-color: #f8f8f8;