diff --git a/01_Topic/topic.tex b/01_Topic/topic.tex
index 666cf52..aa516a5 100644
--- a/01_Topic/topic.tex
+++ b/01_Topic/topic.tex
@@ -1,4 +1,4 @@
-\documentclass{article}
+\documentclass[a4paper]{IEEEtran}
 \usepackage[utf8]{inputenc}
 \usepackage[english]{babel}