diff --git a/docker/Dockerfile b/docker/Dockerfile
index edd6a49..3d503bb 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,5 +1,5 @@
-ARG UBUNTU_DISTR
-FROM ubuntu:22.04
+ARG UBUNTU=22.04
+FROM ubuntu:${UBUNTU}
 
 ARG UID=1000
 ARG GID=1000
@@ -27,7 +27,7 @@ RUN apt-get update -y && \
     apt-get clean && rm -rf /var/lib/apt/lists/* /var/cache/debconf/* /var/log/* /tmp/* /var/tmp/* && \
     localedef -i en_US -c -f UTF-8 -A /usr/share/locale/locale.alias en_US.UTF-8
 
-RUN cd /opt && curl -Lk https://github.com/novnc/noVNC/archive/refs/tags/v{NOVNC_VERSION}.tar.gz | tar xz && \
+RUN cd /opt && curl -Lk https://github.com/novnc/noVNC/archive/refs/tags/v${NOVNC_VERSION}.tar.gz | tar xz && \
     rm v${NOVNC_VERSION}.tar.gz && mv noVNC-${NOVNC_VERSION} novnc && \
     cp /opt/novnc/vnc.html /opt/novnc/index.html