Hi there,
add this PHP snippet to your site to change the Read More label:
add_filter( 'generate_content_more_link_output','tu_change_content_more_link' );
function tu_change_content_more_link() {
return sprintf( '<p class="read-more-container"><a title="%1$s" class="read-more content-read-more" href="%2$s">%3$s</a></p>',
the_title_attribute( 'echo=0' ),
esc_url( get_permalink( get_the_ID() ) . apply_filters( 'generate_more_jump','#more-' . get_the_ID() ) ),
__( 'Continue reading...', 'generatepress' )
);
}
Hey David, I think you have not understood my issue properly. I only want to change the width of the Read More box using CSS code like the image below.

Leo
(@leohsiang)
Give this CSS a shot:
a.read-more.button {
width: 100%;
text-align: center;
}
Adding CSS: https://docs.generatepress.com/article/adding-css/