Search Widget in Navbar

Hello,

I ‘ve been trying to get the search bar in the navbar for some time .
But unfortunately I do not get ahead .

http://www.aviation-company.de

I’ve added a new widget and do not know how to get it into the search bar .

Maybe someone can give you of an important hint .

Here the code in the functions.php

// Adds a widget area to house a Polylang dropdown. See also accompanying css.
if (function_exists('register_sidebar')) {
 register_sidebar(array(
 'name' => 'Extra Widget After Navbar',
 'id' => 'extra-widget',
 'description' => 'Extra widget after the navbar',
 'before_widget' => '<div class="widget %2$s" id="%1$s">',
 'after_widget' => '</div>',
 'before_title' => '<h2>',
 'after_title' => '</h2>'
 ));
}

// Place the widget area after the navbar
add_filter ('__navbar', 'add_my_widget');
function add_my_widget() {
 if (function_exists('dynamic_sidebar')) {
 dynamic_sidebar('Extra Widget After Navbar');
 }
}

And here in the style.css

/*Produktsearch,JB*/
.widget_products_predictive_search{

	float: right;
    width: 20%;
    position: relative;
    bottom: -5px;
    }

Thank you for your help.

best regards

Johannes