make every second chat message display differently

src/reducers/chat.js

@@ -153,7 +153,7 @@ export default function chat(
         ],
       };
       if (messages[channel].length > MAX_CHAT_MESSAGES) {
-        messages[channel].shift();
+        messages[channel].splice(0, 2);
       }
 
       /*

src/styles/default.css

@@ -660,6 +660,14 @@ tr:nth-child(even) {
   overflow-x: hidden;
   overflow-y: scroll;
 }
+
+.chatarea {
+  background-color: #393939;
+}
+.chatarea:nth-child(even) {
+  background-color: #4b4b4b;
+}
+
 .chatinput {
   height: 24px;
   white-space: nowrap;