If you want the whole UI around rendering the content, sure, but you don't need that – it's just an iframe that sets a `data:` URI anyway. The link can just as well be the data URI itself. It'd be a very long link for any non trivial content, but it works just fine without any connectivity.
Seeing as tickets are typically sent in HTML emails anyway the scary looking URI can just be hidden behind a nice anchor tag or something anyway. When the recipient clicks the link, the page will open in a browser and render just fine without any connectivity. Graphics can be embedded in the same way, using `data:` URIs as image tag sources, or in embedded css.
Here's an example, turn off your connection and try this in your browser's address bar:
Seeing as tickets are typically sent in HTML emails anyway the scary looking URI can just be hidden behind a nice anchor tag or something anyway. When the recipient clicks the link, the page will open in a browser and render just fine without any connectivity. Graphics can be embedded in the same way, using `data:` URIs as image tag sources, or in embedded css.
Here's an example, turn off your connection and try this in your browser's address bar:
EDIT: Created another, more complex, example but it's unfortunately too long for HN comments. You can see it here:https://gist.github.com/mstade/597f7da82841b1c27c63c8b383538...
Just copy and paste the raw contents of that file into the address bar and it should render the page.