asom77

I found the filter which worked but I had to add it to main theme function.php
If I add under child theme it shows error.

function mytheme_body_class( $classes ) {

     if( is_page_template('homepage.php') )
          $classes[] = 'custom-layout';

    return $classes;
}
add_filter( 'body_class', 'mytheme_body_class' );

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