add highlight

docs/index.html

@@ -35,11 +35,11 @@
             highlight: [
                 {
                     time: 20,
-                    text: '这是第 20 秒'
+                    text: '123456789'
                 },
                 {
                     time: 120,
-                    text: '这是 2 分钟'
+                    text: '123456789'
                 }
             ]
         });