Remove outline from hostnames

Also removed unused CSS class `.hostnames`.

src/options.scss

@@ -78,7 +78,6 @@ button:focus {
         outline: none;
 }
 
-.hostnames,
 .input-file-hostnames,
 .input-file-url {
         background-color: #222;
@@ -90,11 +89,7 @@ button:focus {
         width: 350px;
 }
 
-.hostnames {
-        width: 100%;
-}
-
-.hostnames,
+.input-file-hostnames,
 .input-file-url:focus {
         outline: none;
 }