Use certbot for let's encrypt certificate
diff --git a/nginx/Dockerfile.entrypoint b/nginx/Dockerfile.entrypoint
index 0c2ff96..515301c 100644
--- a/nginx/Dockerfile.entrypoint
+++ b/nginx/Dockerfile.entrypoint
@@ -4,8 +4,17 @@
 
 {
     domain=${SA_PUBLIC_DOMAIN_NAME:-miau.local}
+    live=/etc/nginx/certs/live
     html=/var/www/html
 
+    if [ ! -f ${live}/${domain}/privkey.pem ]; then
+        mkdir -p ${live}/${domain}
+        cp /etc/ssl/private/sa-selfsigned.key ${live}/${domain}/privkey.pem
+        cp /etc/ssl/certs/sa-selfsigned.crt ${live}/${domain}/fullchain.pem
+        cp /etc/ssl/certs/sa-selfsigned.crt ${live}/${domain}/chain.pem
+        cp /etc/ssl/certs/sa-selfsigned.crt ${live}/${domain}/cert.pem
+    fi
+
     rm -rf ${html}
     cp -a /var/www/simpleid ${html}
 
@@ -22,6 +31,6 @@
 
 chown -R nginx:nginx /var/www/html/
 
-chmod -R a-w /etc/nginx/conf.d/sa.conf /var/www/html/
+chmod -R a-w /etc/nginx/certs/ /etc/nginx/conf.d/sa.conf /var/www/html/
 
 exec /docker-entrypoint.sh "$@"