Logo and menu

Hi, first of all you need a file named functions.php in your child-theme directory. It must contain just the following code.
<?php
Once you createad and uploaded it, add the following code below <?php:

// header content wrapped
add_action('__header', 'tc_header_header_start', 0);
function tc_header_header_start(){
    echo '<div class="tc-header-container container">';
}
add_action('__header', 'tc_header_header_end', 40);
function tc_header_header_end(){
    echo '</div>';
}

The wideness of the area which contains “the three images down” is set via the css rule for the class “container”. With the code above we wrap the header content in a div with the class “container”.
Hope this helps.

No. You have to use 40, no chance.
If you use 30 you have the navbar outside of that container and a div opened inside of it which is closed outside, it’s a mess.

You can do something like:

@media screen and (min-width: 980px){
    .tc-header .navbar-wrapper{
        padding-top: 4%;
    }
}
@media screen and (min-width: 1200px){
    .tc-header .navbar-wrapper{
        padding-top: 3%;
    }
}