1. For intro text, please try to add this CSS code to the Customize > Additional Style:
It seems the intro text style has been overridden by another style.
2. For optimizing the page speed please check this article https://support.jegtheme.com/2017/11/increase-google-page-speed-for-jnews/. Also, we recommend you to use WP Super cache plugin instead of W3 Total Cache.