diff --git a/asciinema/compose.yaml b/asciinema/compose.yaml
index 7cef1fb..f2a5b23 100644
--- a/asciinema/compose.yaml
+++ b/asciinema/compose.yaml
@@ -3,13 +3,16 @@ services:
     image: ${ASCIINEMA_IMAGE:-ghcr.io/asciinema/asciinema-server:latest}
     container_name: ${ASCIINEMA_COMPOSE_PROJECT_NAME}_app
     restart: unless-stopped
+    entrypoint: ["/entrypoint-wrapper.sh"]
+    command: ["start"]
     networks:
       - compose_network
     extra_hosts:
       - "smtp.ionos.de:213.165.67.97"
     volumes:
       - asciinema_data:/var/opt/asciinema
-      - ./theme/custom.css:/app/assets/css/custom.css:ro
+      - ./theme/custom.css:/opt/app/lib/asciinema-1.0.0/priv/static/assets/custom.css:ro
+      - ./entrypoint-wrapper.sh:/entrypoint-wrapper.sh:ro
     environment:
       SECRET_KEY_BASE: ${ASCIINEMA_SECRET_KEY}
       URL_HOST: ${ASCIINEMA_TRAEFIK_HOST}
diff --git a/asciinema/entrypoint-wrapper.sh b/asciinema/entrypoint-wrapper.sh
new file mode 100755
index 0000000..fb4b930
--- /dev/null
+++ b/asciinema/entrypoint-wrapper.sh
@@ -0,0 +1,17 @@
+#!/bin/sh
+set -e
+
+# Inject custom CSS into app.css if it exists
+if [ -f /opt/app/lib/asciinema-1.0.0/priv/static/assets/custom.css ]; then
+  echo "Injecting custom CSS into app.css..."
+  cat /opt/app/lib/asciinema-1.0.0/priv/static/assets/custom.css >> /opt/app/lib/asciinema-1.0.0/priv/static/assets/app.css
+  # Also append to the hashed version
+  CSS_FILE=$(ls /opt/app/lib/asciinema-1.0.0/priv/static/assets/app-*.css 2>/dev/null | head -1)
+  if [ -n "$CSS_FILE" ]; then
+    cat /opt/app/lib/asciinema-1.0.0/priv/static/assets/custom.css >> "$CSS_FILE"
+    echo "Custom CSS injected successfully"
+  fi
+fi
+
+# Execute the original entrypoint
+exec /opt/app/bin/asciinema "$@"