diff --git a/server/Dockerfile b/server/Dockerfile
index 6d7c87e..82a66a4 100644
--- a/server/Dockerfile
+++ b/server/Dockerfile
@@ -29,8 +29,11 @@ WORKDIR /web
 
 # Card images are committed in the repository (CC0 woodcut napoletane deck);
 # web/fetch-cards.sh can regenerate them.
-COPY web/Cargo.toml web/Cargo.lock web/index.html web/style.css web/Trunk.toml ./
+COPY web/Cargo.toml web/Cargo.lock web/index.html web/style.css web/theme.css web/Trunk.toml ./
 COPY web/assets ./assets
+# Vendored Bootstrap (MIT) loaded by index.html; kept out of the CDN so the
+# image builds and runs without network access.
+COPY web/vendor ./vendor
 COPY web/src ./src
 
 # --public-url makes trunk emit asset URLs under /static, the prefix Granian