There are 2 helper classes to reduce the space between fullwidth sections:
<div class="is-fullwidth bg-section rel h-100 is-parallax is--flex pull-top"
...
<div class="is-fullwidth bg-section rel h-100 is-parallax is--flex pull-btm"
...
In default fullwidth Jimdo images you need to use the button "Alternative text & caption"
There are some additional helper classes in CSS that can be used only for Widget/HTML:
/* pull margins */
.pull-top-10 {
margin-top:-10px!important;
}
.pull-top-20 {
margin-top:-20px!important;
}
.pull-top-30 {
margin-top:-30px!important;
}
.pull-top-40 {
margin-top:-40px!important;
}
.pull-top-50 {
margin-top:-50px!important;
}
.pull-btm-10 {
margin-bottom:-10px!important;
}
.pull-btm-20 {
margin-bottom:-20px!important;
}
.pull-btm-30 {
margin-bottom:-30px!important;
}
.pull-btm-40 {
margin-bottom:-40px!important;
}
.pull-btm-50 {
margin-bottom:-50px!important;
}
The above helper classes don't work for the first module in your content, so it's not possible to reduce the space between the header/hero image and content.