[web-animations-1][editorial] Delete redundant CSS

These styles are part of base.css now.

Author: fantasai

web-animations-1/Overview.bs

@@ -26,24 +26,6 @@ div.informative-bg h4 {
   background: none;
 }
 
-div.switch > dl {
-  padding-left: 2em;
-}
-
-div.switch > dl > dt > p {
-  display: inline;
-}
-
-div.switch > dl > dt:before {
-  content: '\21AA';
-  padding: 0 0.5em 0 0;
-  display: inline-block;
-  width: 1em;
-  text-align: right;
-  line-height: 0.5em;
-  margin-left: -1.3em;
-}
-
 .attributes::before, .methods::before,
 .parameters::before, .exceptions::before,
 .constructors::before, .members::before {