WordPress footer walker

//Class custom

class Footer_Walker extends Walker_Nav_Menu {
  function start_el(&$output, $item, $depth = 0, $args = array(), $id = 0) {
    $classes = empty($item->classes) ? array () : (array) $item->classes;
    $class_names = join(' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item,1,4 ) ); //设置权重防止filter冲突
    !empty ( $class_names ) and $class_names = ' class="'. esc_attr( $class_names ) . '"';
    $output .= '';
    $attributes  = '';
    !empty( $item->attr_title ) and $attributes .= ' title="'  . esc_attr( $item->attr_title ) .'"';
    !empty( $item->target ) and $attributes .= ' target="' . esc_attr( $item->target     ) .'"';
    !empty( $item->xfn ) and $attributes .= ' rel="'    . esc_attr( $item->xfn        ) .'"';
    !empty( $item->url ) and $attributes .= ' href="'   . esc_attr( $item->url        ) .'"';
    $title = apply_filters( 'the_title', $item->title, $item->ID );
    $item_output = $args->before
    ."<div class='clear-fix w-100'></div>"
    . "<a class='link link-gray size-18 animsition-link' $attributes data-hover='$title'>"
    . $args->link_before
    . $title
    . '</a>'
    . $args->link_after
    . $args->after;
    $output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
  }
}