The rpress_button_colors filter is applied to the get button colors, returns an array of button colors of RestroPress. It receives one parameters:
return apply_filters( ‘rpress_button_styles’, $styles );
The sample below shows an example of how you could modify it:
function rpress_button_colors_callback( $colors ) { $colors = array( 'salmon' => array( 'label' => __( ' Salmon', 'restropress' ), 'hex' => ' #FA8072' )); return $colors; } add_filter( ' rpress_button_colors’, 'rpress_button_colors_callback', 10, 1 );