Use Markdown to write your slides
If the first line of a slide is an image element, then it will be used for the background.
If you prefer to host your deck file on the internet so that you can share your slide show, you can enter the url of your hosted file instead of the slide content.
It might look like this.
If the image url ends with jpeg, png, gif or svg the slide will have an image background
If the url ends in webm, mp4 or mov it will have a video background
Any other url will set the slide to have an iframe background
You can use relative urls for assets linked in your slides if those assets are hosted in the same folder as your deck file.
This is useful for preparing an offline presentation and later moving it online.
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