diff --git a/index.html b/index.html
index 09c87f1..5b738ec 100644
--- a/index.html
+++ b/index.html
@@ -5,12 +5,7 @@
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Document</title>
-    <style>
-        span{
-            font-weight: bolder;
-            color: green;
-        }
-    </style>
+
 </head>
 <body>
     <h1>Bản demo 1.0 cho ngịch git thử này</h1>
diff --git a/main.css b/main.css
new file mode 100644
index 0000000..88598c7
--- /dev/null
+++ b/main.css
@@ -0,0 +1,4 @@
+        span{
+            font-weight: bolder;
+            color: green;
+        }
\ No newline at end of file
