diff --git a/app/build.gradle b/app/build.gradle
index 0849fd1..ad48b22 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 28
+    buildToolsVersion '27.0.3'
 
     defaultConfig {
         applicationId "cn.iwgang.countdownviewdemo"
         minSdkVersion 15
-        targetSdkVersion 23
+        targetSdkVersion 28
         versionCode 1
         versionName "1.0"
     }
@@ -21,9 +21,10 @@ android {
 
 dependencies {
     compile fileTree(dir: 'libs', include: ['*.jar'])
-    compile 'com.android.support:appcompat-v7:23.3.0'
+    //noinspection GradleCompatible
+    implementation 'com.android.support:appcompat-v7:27.0.0'
     compile 'com.github.iwgang:familiarrecyclerview:1.3.0'
     compile 'cn.qqtheme.framework:ColorPicker:1.1.3'
-//    compile project(':library')
-    compile 'com.github.iwgang:countdownview:2.1.6'
+    compile project(':library')
+    // compile 'com.github.iwgang:countdownview:2.1.6'
 }
diff --git a/build.gradle b/build.gradle
index 3cf5f30..03e0efb 100644
--- a/build.gradle
+++ b/build.gradle
@@ -2,9 +2,10 @@
 buildscript {
     repositories {
         jcenter()
+        maven { url 'https://maven.google.com/'}
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.2.0'
+        classpath 'com.android.tools.build:gradle:3.6.4'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
@@ -13,5 +14,6 @@ buildscript {
 allprojects {
     repositories {
         jcenter()
+        maven { url 'https://maven.google.com/'}
     }
 }
\ No newline at end of file
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 0c71e76..40bb4ea 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Wed Apr 10 15:27:10 PDT 2013
+#Fri Dec 11 15:46:33 CST 2020
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.2.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
diff --git a/library/build.gradle b/library/build.gradle
index aff5590..75fa012 100644
--- a/library/build.gradle
+++ b/library/build.gradle
@@ -1,12 +1,12 @@
 apply plugin: 'com.android.library'
 
 android {
-    compileSdkVersion 21
+    compileSdkVersion 28
     buildToolsVersion '25.0.2'
 
     defaultConfig {
         minSdkVersion 10
-        targetSdkVersion 21
+        targetSdkVersion 28
         versionCode 1
         versionName "1.0"
     }
diff --git a/library/src/main/java/cn/iwgang/countdownview/BaseCountdown.java b/library/src/main/java/cn/iwgang/countdownview/BaseCountdown.java
index d26533e..0c5ee1d 100644
--- a/library/src/main/java/cn/iwgang/countdownview/BaseCountdown.java
+++ b/library/src/main/java/cn/iwgang/countdownview/BaseCountdown.java
@@ -27,6 +27,7 @@ class BaseCountdown {
     protected String mSuffix, mSuffixDay, mSuffixHour, mSuffixMinute, mSuffixSecond, mSuffixMillisecond;
     protected float mSuffixDayTextWidth, mSuffixHourTextWidth, mSuffixMinuteTextWidth, mSuffixSecondTextWidth, mSuffixMillisecondTextWidth;
     protected boolean isDayLargeNinetyNine;
+    protected boolean isHourLargeNinetyNine;
     protected Paint mTimeTextPaint, mSuffixTextPaint, mMeasureHourWidthPaint;
     protected float mLeftPaddingSize;
     protected float mSuffixDayLeftMargin, mSuffixDayRightMargin;
@@ -730,6 +731,21 @@ public boolean handlerDayLargeNinetyNine() {
         return isReLayout;
     }
 
+    public boolean handlerHourLargeNinetyNine() {
+        boolean isReLayout = false;
+        if (isShowHour && isConvertDaysToHours) {
+            // handler large ninety nine
+            if (!isHourLargeNinetyNine && mHour > 99) {
+                isHourLargeNinetyNine = true;
+                isReLayout = true;
+            } else if (isHourLargeNinetyNine && mHour <= 99) {
+                isHourLargeNinetyNine = false;
+                isReLayout = true;
+            }
+        }
+        return isReLayout;
+    }
+
     public void setTimes(int day, int hour, int minute, int second, int millisecond) {
         mDay = day;
         mHour = hour;
diff --git a/library/src/main/java/cn/iwgang/countdownview/CountdownView.java b/library/src/main/java/cn/iwgang/countdownview/CountdownView.java
index 097df58..ceb0e71 100644
--- a/library/src/main/java/cn/iwgang/countdownview/CountdownView.java
+++ b/library/src/main/java/cn/iwgang/countdownview/CountdownView.java
@@ -268,7 +268,8 @@ public void updateShow(long ms) {
             }
         }
 
-        if (mCountdown.handlerAutoShowTime() || mCountdown.handlerDayLargeNinetyNine()) {
+        if (mCountdown.handlerAutoShowTime() || mCountdown.handlerDayLargeNinetyNine()
+                || mCountdown.handlerHourLargeNinetyNine()) {
             reLayout();
         } else {
             invalidate();