Deploy main eacf1e7 to prod

Replaces #559, which conflicted.

Model: opus-5-5

script/check

@@ -1,7 +1,8 @@
 #!/bin/sh
-# script/check: run all checks (test, lint, fmt-check). Our own
-# extension to scripts-to-rule-them-all. Must not modify any files.
-# Generic: usually needs no adaptation.
+# script/check: run all checks (test, lint, fmt-check, css-check). Our own
+# extension to scripts-to-rule-them-all. test, lint and css-check are
+# Docker builds; fmt-check runs gofmt on the host. Writes nothing.
+# Generic, apart from css-check.
 set -eu
 
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
@@ -10,6 +11,7 @@ main() {
     "$SCRIPT_DIR/test"
     "$SCRIPT_DIR/lint"
     "$SCRIPT_DIR/fmt-check"
+    "$SCRIPT_DIR/css-check"
 }
 
 main "$@"