Improve options page UI

Now the UI is a little bit more serious.

Fixed: translateselectedtext:12
Change-Id: If00acdd5a1148cb1223b959b4e32ab4029b3d09f
diff --git a/src/options/elements/options-editor/languages-editor.js b/src/options/elements/options-editor/languages-editor.js
index 7845a65..4265d50 100644
--- a/src/options/elements/options-editor/languages-editor.js
+++ b/src/options/elements/options-editor/languages-editor.js
@@ -20,7 +20,7 @@
           width: 300px;
           height: 250px;
           border: 1px solid #ccc;
-          background-color: #E3F2FD;
+          background-color: #fafafa;
           overflow: auto;
         }
 
@@ -36,7 +36,7 @@
           align-items: center;
           padding: 15px;
           border-bottom: 1px dashed #ddd;
-          background-color: #EEF7FD;
+          background-color: white;
           -webkit-user-select: none;
         }