auto merge of #10849 : adridu59/rust/patch-css, r=alexcrichton

rustdoc:
- fix search-bar layout

doc: CSS:
- switch to native pandoc toc depth
- rm some dead code
- clamp width to be readable (we're not Wikipedia!)
- don't background-color titles, it's bloating
- make syntax-highlighting colors inline with rust-lang.org
- space indents

@alexcrichton

Author: bors

doc/manual.inc

@@ -5,8 +5,6 @@
     padding-left: 2em;
   }
   #influences blockquote p:last-child {
-    display: block;
-    line-height: 1.428571429;
-    color: #999999;
+    color: #999;
   }
-</style>
+</style>