diff --git a/src/main.cpp b/src/main.cpp
index d4b2ebd..bdd97d5 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -32,7 +32,8 @@ struct page_handler
 	void operator()(const httplib::Request& req, httplib::Response& res)
 	{
 		std::string data_content = Files::load(path);
-		std::string page = std::vformat(DATA_INDEX, std::make_format_args(get_theme(req), data_content));
+		std::string theme = get_theme(req);
+		std::string page = std::vformat(DATA_INDEX, std::make_format_args(theme, data_content));
 		res.set_content(page, "text/html");
 	}
 };
@@ -72,7 +73,8 @@ void put_contact(const httplib::Request& req, httplib::Response& res)
 
 void error_handler(const httplib::Request& req, httplib::Response& res)
 {
-	std::string page = std::vformat(DATA_INDEX, std::make_format_args(get_theme(req), DATA_ERROR));
+	std::string theme = get_theme(req);
+	std::string page = std::vformat(DATA_INDEX, std::make_format_args(theme, DATA_ERROR));
 	res.set_content(page, "text/html");
 }