Style devise error messages

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/stylesheets/sections/login.scss

@@ -46,3 +46,10 @@ body.login-page{
     margin: 2px;
   }
 }
+
+.devise-errors {
+  h2 {
+   font-size: 14px;
+   color: #a00;
+  }
+}