diff --git a/app/build.gradle b/app/build.gradle
index 0849fd1..e6144a2 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -1,13 +1,13 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 23
-    buildToolsVersion '25.0.2'
+    compileSdkVersion 31
+    buildToolsVersion '31'
 
     defaultConfig {
         applicationId "cn.iwgang.countdownviewdemo"
         minSdkVersion 15
-        targetSdkVersion 23
+        targetSdkVersion 31
         versionCode 1
         versionName "1.0"
     }