How to use a video as a Squarespace background
What you’ll need: A link to a Vimeo or YouTube video you plan to use as the background, a mobile fallback image in a JPG or PNG format, and a page with a page section in Squarespace 7.1
How to use a video for a page section background:
Select edit on the top left hand side of the site preview
Hover over the page section you want to add the background video to
Click on the edit page section icon that appears on the right hand side of the page section (it’s the icon on the far left of the icons that show up on a hover)
Navigate to the background tab
Toggle from image to video
Paste the YouTube or Vimeo link
Optional: adjust the settings for width, filter and playback speed
Optional but strongly recommended: upload a mobile fallback image by dragging and dropping a PNG or JPG image file where it says add an image
Important info: You can also upload a GIF as a page section background, which allows you to have movement even on mobile. Check out this tutorial on how to add a GIF for a page section background in Squarespace.