feat: add the organisation logo and banner

README.md

@@ -1,3 +1,10 @@
 # .github
 
-The public profile of the [exim-container](https://github.com/exim-container) organisation, in `profile/README.md`.
+The public profile of the [exim-container](https://github.com/exim-container) organisation.
+
+| Path | Content |
+|---|---|
+| `profile/README.md` | the page shown on the organisation home |
+| `brand` | the logo and the banner, as SVG sources and PNG renderings |
+
+See [docs](docs/brand.md) to render the PNG files.

docs/brand.md

@@ -0,0 +1,8 @@
+# Brand
+
+The PNG files are rendered from the SVG sources with `rsvg-convert` (package `librsvg2-bin`):
+
+```sh
+rsvg-convert -w 512 -h 512 brand/logo.svg -o brand/logo.png
+rsvg-convert -w 1280 -h 640 brand/banner.svg -o brand/banner.png
+```

profile/README.md

@@ -1,3 +1,5 @@
+<p align="center"><img src="../brand/banner.png" alt="Exim Container" width="640"></p>
+
 Container images of the [Exim](https://www.exim.org/) mail transfer agent, built from the upstream release tags on Debian 13, for amd64 and arm64. A new Exim release or a Debian security update publishes a new image on its own.
 
 | Repository | Content |