scottscottsee

This is perfect! Thank you so much! You have no idea how helpful this was!
For some reason, the scale of the second image wasn't quite working, but I just added "background-size: 100%;" and that fixed it. 
Thanks!

Since you can grab the uploaded image url, I can suggest you use psuedo :after selector for this, using the unique url in the link tag
a[href="/alley-house-1"]:after { background: url(https://images.squarespace-cdn.com/content/v1/5e9f52c…/1591746790510-TLM3OCA969QR248359Q9/ke17ZwdGBToddI8pDm48kNIz01GxeNglza_traDdevsUqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKck_3oyjxD2E6g656zntaR4vQBwPCV_Yc9BnFEdXAQ6xzMr4wPFfphDwEQcs_2fgoE/Pavilion+House+Sect_wt-1.jpg?format=300w); content: ""; position: absolute; width: 100%; height: 100%; top: 0; left: 0; background-repeat: no-repeat; background-position: center; opacity: 0; transition: opacity 0.75s; } a[href="/alley-house-1"]:hover:after { opacity: 1; } Output: http://recordit.co/HDXB6rAspQ

This is amazing! Thank you so much!
 

Hey @scottscottsee

You can copy and paste the code from this link and add it to Setting -> Advanced -> Code Injection -> Footer

https://gist.github.com/ryandejaegher/d7e96e60816a4cf76d1d69b9c162ed09

Tested and works on your site but may still require some tweaking. Let me know how it works. 

Update 5/26/2020: Squarespace has added the ability to add image descriptions/captions to 7.1 gallery sections. See here. There are some limitations, such as not appearing in lightbox view and not supporting multiple lines. So, the workaround below may still be of use.
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Hi @dan3.
Looking at the underlying gallery code, it appears that image descriptions are in-the-works to one degree or another. In the mean time, I've created a bit of code you can use to add image descriptions/captions to gallery sections in Squarespace 7.1 .
View Demo Site
JavaScript
Insert via sitewide footer code injection. If you only want to add descriptions to some (not all) galleries, pass your own CSS selector into addGalleryItemDescriptions() (for example: "section[data-section-id='5db1f73f7a30760db464bb02']") For images within a targeted gallery that you do not want a description to appear, you must enter a space as the description (otherwise the filename will show). <script> /** * Add descriptions/captions to galleries in Squarespace 7.1. * JavaScript * © @brandon (Squarespace Forum User) * This software is provided "as is", without warranty of any kind, express or implied. */ document.addEventListener("DOMContentLoaded", function() { addGalleryItemDescriptions(); function addGalleryItemDescriptions(gs, gdzs) { var a=['querySelectorAll','section.gallery-section,\x20.gallery-lightbox','length','[class*=\x27-item\x27]:not([class*=\x27item-\x27])','getElementsByTagName','img','alt','trim','createElement','div','className','gallery-item-description','textContent','appendChild'];var b=function(c,d){c=c-0x0;var e=a[c];return e;};(function(c,d){var e,f,g,h,i,j,k;e=document[b('0x0')](c?c:b('0x1'));i=e[b('0x2')];while(i--){f=e[i][b('0x0')](d?d:b('0x3'));j=f[b('0x2')];while(j--){g=f[j][b('0x4')](b('0x5'))[0x0][b('0x6')][b('0x7')]();if(g){h=document[b('0x8')](b('0x9'));h[b('0xa')]=b('0xb');h[b('0xc')]=g;f[j][b('0xd')](h);}}}}(gs,gdzs)); } }); </script>  
CSS
Insert in "Customer CSS", via the CSS Editor. The CSS below is very basic, adding a white box around the description and generally placing it at the bottom. You can customize to your heart's content. /** * Add descriptions/captions to galleries in Squarespace 7.1. * CSS * © @brandon (Squarespace Forum User) * This software is provided "as is", without warranty of any kind, express or implied. */ body { width: 100%; } section.gallery-section [class*='-item']:not([class*='-item-']):not([class*='-reel']):not([class*='-slideshow']) { position: relative; } .gallery-item-description { font-family: "Roboto", sans-serif; font-size: 16px; color: black; } .gallery-grid, .gallery-strips, .gallery-masonry, .gallery-reel, .gallery-fullscreen-slideshow { .gallery-item-description { position: absolute; width: 100%; bottom: 0; background-color: rgba(255, 255, 255, 0.7); padding: 2% 6%; box-sizing: border-box; } } .gallery-slideshow, .gallery-fullscreen-slideshow, .gallery-reel { .gallery-item-description { padding: 10px 25px; opacity: 1; transition: opacity 0.2s; } .gallery-slideshow-item:not([data-in="true"]), .gallery-fullscreen-slideshow-item:not([data-in="true"]), figure[style*="-9999"] { .gallery-item-description { opacity: 0; } } } .gallery-slideshow { .gallery-slideshow-list { position: static; } .gallery-slideshow-item-wrapper, .gallery-item-description { flex: 1 1 auto; } } .gallery-reel { .gallery-item-description { text-align: center; left: 50%; transform: translateX(-50%); } &[data-width="inset"], &[data-width="inset"] { .gallery-item-description { max-width: 88vw; } } &[data-width="full-bleed"] { .gallery-item-description { max-width: 100vw; } } } .gallery-lightbox .gallery-item-description { margin-top: 1em; padding: 1em 2em; background-color: rgba(225, 225, 225, 1); transition: opacity 0.1s ease-out; } .gallery-lightbox-item[data-in=false] .gallery-item-description { opacity: 0; } This is of course experimental. Do let me know how it works for you, or if you have questions.
If you reply to this post, please do not quote the code in your reply. Doing so will create copies of the code which A) I would prefer not be copied and B) will propagate old versions of the code which are likely to fall out of date.
-Brandon