Try this:
add_action( 'wp', 'tu_disable_global_elements' );
function tu_disable_global_elements() {
if ( is_single() ) {
remove_action( 'generate_before_header','generate_top_bar', 5 );
remove_action( 'generate_header','generate_construct_header' );
remove_action( 'generate_footer','generate_construct_footer' );
add_filter( 'generate_show_title', '__return_false' );
}
}
Then add this CSS:
.single .secondary-navigation {
display: none;
}
.single .container.grid-container {
max-width: 100%;
}
.single.no-sidebar.separate-containers .site-main {
margin: 0;
}
.single.separate-containers .inside-article,
.single.one-container .site-content {
padding: 0;
}