Change ma_admin_options_init() to:
public function ma_admin_options_init(){
register_setting('ma_admin_styler', 'ma_admin_styler', array( $this,'ma_admin_styler_validate'));
add_settings_section('main_section', '', array( $this,'section_text_default'), 'ma_admin_styler');
add_settings_field('error_font_color', 'Error Font Color', array( $this,'ma_error_font_color'), 'ma_admin_styler', 'main_section');
}
The fourth parameter of add_settings_section() and add_settings_field() is $page and that needs to match the page ID set in add_options_page().