Overlapping Elements on Sections

Hiya,

I'm trying to do something really basic, but struggling a bit with the css. I'd like to overlap an element, specifically a .png image with a transparent image over the section below it. 

I found this useful: https://forum.squarespace.com/topic/158707-overlap-images-and-sections-with-71/ 

-->

/* remove section bottom padding */
[data-section-id="5ddd4eb4522cc3312c5226a6"] .content-wrapper {
    padding-bottom: 0 !important;
}
/* remove overflow hidden */
div#block-yui_3_17_2_1_1587085802684_25650 .image-block-wrapper {
    overflow: visible !important;
}
/* overlap image */
div#block-yui_3_17_2_1_1587085802684_25650 img {
    width: auto !important;
    bottom: -20% !important;
    top: unset !important;
    right: 0;
    z-index: 999;
}

However, it then causes the image to be slightly reduced by the section below it instead of overlapping. I think I just need a a bit of code on the box below to allow it, but everything I've tried doesn't work. Any help?

Much appreciated! 

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