a function like this to remove the image-sizes enfold likes to have:

function remove_enfold_image_sizes() {
// do NOT remove widget size, is used in backend portfolio items!
// remove_image_size('widget');
  remove_image_size('square');
  remove_image_size('featured');
  remove_image_size('featured_large');
  remove_image_size('portfolio');
  remove_image_size('portfolio_small');
  remove_image_size('gallery');
  remove_image_size('magazine');
  remove_image_size('masonry');
  remove_image_size('entry_without_sidebar');
  remove_image_size('entry_with_sidebar');
  remove_image_size('shop_thumbnail');
  remove_image_size('shop_catalog');
  remove_image_size('shop_single'); 
  remove_image_size('shop_gallery_thumbnail');
}
add_action('init', 'remove_enfold_image_sizes');

i guess does only influence the calculation of newly uploaded images.
The former uploads are not influenced on that. So these sizes are still in your uploads folder. (have a look by ftp inspection if this is the fact)
the use of Force Regenerate Thumbnails – removes those already calculated image-sizes that are not registered.

btw: where does the p-tag come from : p.ondertitel
See DOM:

i’m participant as you are – so i do not see any private content area.

so you have to wait for mods here

#top .avia-tooltip.avia-tt {
  display: none !important;
}

i’m participant as you are – so i do not see any private content area.

on general layout – Maximum Container Width – this is the value i pull out in the snippet for the setting

$responsive_size = avia_get_option('responsive_size');

If you have there a 100% width set – then it wil be synchronized in the snippet too.
If that is the case – you have to use the other snippet with the “hard-coded” width and replace th 1310px with your 1400px now:

function grid_layout_notfull(){
?>
<script>
(function($){
	$('.av-layout-grid-container.grid-notfull' ).each(function() {
		var notfullID = $(this).attr('id');
		$(this).hasClass('main_color') ? $(this).wrap('<div class="main_color notfullsize '+notfullID+'"></div>') : '';
		$(this).hasClass('alternate_color') ? $(this).wrap( '<div class="alternate_color notfullsize '+notfullID+'"></div>') : '';
	});
	$('.notfullsize').css({"clear": "both", "width": "100%" , "float": "left" , "position": "static" , "min-height": "100px" });
	$('.grid-notfull').css({"max-width": "1400px", "margin": "0 auto" , "padding": "0 50px"});
})(jQuery);
</script>
<?php
}
add_action('wp_footer', 'grid_layout_notfull');

btw.: https://github.com/KriesiMedia/enfold-library/blob/master/actions%20and%20filters/Layout/avf_post_nav_settings.php

with this snippet you do not even need to set the enfold options on post-navigation.
You can set with that filter even to loop:

function my_avf_post_nav_settings( array $settings ){
  if( true === $settings['is_hierarchical'] ){
    $settings['skip_output'] = true;
    return $settings;
  } 
  // the post-types inside the array are allowed to have post-navigation
  if( ! in_array( $settings['type'], array( 'post', 'portfolio' ) ) ){ 
    $settings['skip_output'] = true;
    return $settings;
  }
  $settings['loop_post_nav'] = true;
  $settings['same_category'] = true;
  $settings['is_fullwidth'] = false;
  $settings['skip_output'] = false; 
  return $settings;
}
add_filter( 'avf_post_nav_settings', 'my_avf_post_nav_settings', 10, 1 );

btw. if you set this (is_hierarchical) condition to false – then even pages will have post-navigation

place your contact form inside a 1/1 container.
give a custom ID to that 1/1 container e.g. my-contactform
give a custom class to that 1/1 container mfp-hide
place a button on your site – with manual link : #my-contactform – and custom class: open-popup-link
(because custom class of the button goes to its wrapper the selector .open-popup-link a will work.

btw. in the meantime you do not need this callback .
if you place inside your child-theme functions.php :

add_filter( 'avf_default_lightbox_no_scroll', '__return_true' );

You’re talking about the grid row element, right?

Edit: sadly you did not post a link to your page – but your screenshot is clear enough – i found your site now.
Because it looks exactly the same when you set a grid-row by css to to be not full-width, I thought you had used this element.

____________

So – why don’t you put the portfolio grid inside a 1/1 Container
The Color-Section can have the one background-color – and the 1/1 Container a different one.

if you then do not want on top and bottom of the 1/1 Container the background-color of the Section just remove padding-top and padding-bottom of 50px.

a pure css solution is perhaps not possible.

i have my snippet for child-theme functions.php :

function grid_layout_notfull(){
$responsive_size = avia_get_option('responsive_size');
?>
<script>
(function($){
  $('.av-layout-grid-container.grid-notfull' ).each(function() {
    var notfullID = $(this).attr('id');
    $(this).hasClass('main_color') ? $(this).wrap('<div class="main_color notfullsize '+notfullID+'"></div>') : '';
    $(this).hasClass('alternate_color') ? $(this).wrap( '<div class="alternate_color notfullsize '+notfullID+'"></div>') : '';
  });
  $('.notfullsize').css({"clear": "both", "width": "100%" , "float": "left" , "position": "static" , "min-height": "100px" });
  $('.grid-notfull').css({"max-width": "<?php echo $responsive_size; ?>" , "margin": "0 auto" , "padding": "0 50px"});
})(jQuery);
</script>
<?php
}
add_action('wp_footer', 'grid_layout_notfull');

what you had to do: give a custom class to the grid-row element: grid-notfull
see: https://webers-testseite.de/grid-row-alb/

the difference between green color-section to following grid-row on my testpage comes from the standard padding of grid-cells of 30px

PS: the ID of the grid-row element goes to its wrapper as class.

Assign a custom class to this gallery – and reduce the value for the maximum width – as on blog pages. e.g: 800px

.avia-gallery.your-custom-class {
  max-width: 800px;
  margin: 0 auto;
}

you can decide to show on grid a smaller version of your images – and in light-box to show the full image. On masonry-gallery you can set to have different column-counts on responsive case.

See: https://webers-testseite.de/condonp/

Are you talking about the tooltips displayed by the browser itself when hovering over the image?
They appear automatically if the image has a title attribute.

However, if you have a gallery that displays images in a lightbox, this title attribute is also displayed as text in the bottom bar of the lightbox. Completely removing the title tag would therefore be suboptimal. For galleries, you can switch to displaying the description or caption instead, but this is not possible for all Enfold elements.
So if it only affects the galleries on your site, you could do that, but you would then have to update the description of the images, for example.

There is a snippet that, when placed in the child theme’s functions.php, temporarily removes this title tag on hover but adds it back when clicked:

function temporary_removal_title_tags(){
?>
<script>
  window.onload = function() {
    var elementsWithTitle = document.querySelectorAll('a, img, *[title]');
    for (var i = 0; i < elementsWithTitle.length; i++) {
        var element = elementsWithTitle[i];

        element.setAttribute("data-original-title", element.title);

        element.addEventListener("mouseenter", function() {
            this.title = ""; 
        });

        element.addEventListener("mouseleave", function() {
            this.title = this.getAttribute("data-original-title"); 
        });

        element.addEventListener("mousedown", function() {
            this.title = this.getAttribute("data-original-title");
        });
    }
  };
</script>
<?php
}
add_action('wp_footer', 'temporary_removal_title_tags');

here you see that this script is working for all anchor elements or images – or all elements that have a title-tag

this belongs to paragraph margin setting. So maybe it is enogh to only get rid of default margin-top value on first p tag.

#top p:first-child {
  margin-top: 0 ;
}

maybe that option for logo and Navigation on Enfold – Header : “Let Logo And Menu Position Adapt To Browser Window” is a possibility.
Because your navigation is overlapping your logo on smaller screens.

Open that image link in your browser: https://dapoostkapelle.nl/wp-content/uploads/2025/06/First_business_card_5.png

you then can see the whitespace around it.

hm – if so – then it had to be a part of your layerslider – because on my testpage i got an advanced layerslider too on top – but ajax search acts normal.
https://webers-testseite.de
or https://webers-testseite.de/advanced-layerslider/

sorry Typo in link