How to remove random jump on image when zooming in on it - html

Question

when I press on an image its supposed to blow up into a larger picture. However, I changed the size so the image isn't fully touching the bottom and top of the screen by changing the height to 90vh. However, now when I press the image you can see it shift up that 10vh before expanding the image. Can someone help me remove that jump?
https://darrientu.com/
.pswp { height:100vh !important;
margin:auto!important;top:0 !important;
bottom:0 !important;
}
.pswp__scroll-wrap {
height:90vh !important;margin:auto!important;top:0 !important;
bottom:0 !important;
}

Answer 1

It may be worth undoing any styling that you've applied to it and see if this kind of functionality is supported out of the box:
Using the barsSize option:
https://photoswipe.com/documentation/options.html
Or the parseVerticalMargin event:
https://photoswipe.com/documentation/api.html
I was able to achieve a gap at the top and bottom of the image at the PhotoSwipe demo site by selecting All Controls and adding the styles below to hide/disable the UI with CSS:
.pswp__ui {
opacity: 0!important;
pointer-events: none;
}
Using that in combination with the barsSize option should allow you to customise how big the gap is between the image and the browser viewport, though you probably won't be able to use vh as a unit, and will need to use something like Math.round(window.innerHeight*.1) to calculate 10% view height, or use a pixel value instead.
It's also worth looking into the Custom HTML in Slides topic in the documentation, as you may be able to add a spacer div before and after your image.
For a CSS only fix:
If you don't have access to change how PhotoSwipe is initialised, then the CSS below makes the animation less jumpy on your site, however, it does make the image go to full height first for a moment, before transitioning to 90vh.
Remove:
.pswp__scroll-wrap {
height: 90vh !important;
}
Add:
.pswp__scroll-wrap {
transition: transform 222ms cubic-bezier(.4,0,.22,1);
}
.pswp--animated-in .pswp__scroll-wrap {
transform: scale(.9);
}

Answer 2

To resolve the bounce, please change height: 90vh !important line under .pswp__scroll-wrap selector to 100vh. Like so:
.pswp__scroll-wrap {
height: 100vh !important;
margin: auto !important;
top: 0 !important;
bottom: 0 !important;
}
If you still want to have padding on top & bottom of the images while removing bounce bug, then either downsize the thumbnail image (one that is not used for slider) to match the full sized one (on that is duplicated via slider and scaled up) or add some kind of padding to the images.
Another workaround is to add padded blocks in .pswp__scroll-wrap:before and .pswp__scroll-wrap:after like so:
.pswp__scroll-wrap:before,
.pswp__scroll-wrap:after {
display: block;
content: "":
padding: 50px; // Set this to your preferred padding!
background: #ffffff; // also add transition for background, so it fades in nicely!
}
I couldn't find code where you defined slide thumbnail size prior the scaling, but my guess is that resizing it would also help keep the padding while having no bounce issue.
The whole issue is around you having those 90vh under the wrap while resizing the duplicate of the original image.