diff --git a/app/src/main/java/com/kyhsgeekcode/dereinfo/SongRecyclerViewAdapter.kt b/app/src/main/java/com/kyhsgeekcode/dereinfo/SongRecyclerViewAdapter.kt
index 454f431..46e9bac 100644
--- a/app/src/main/java/com/kyhsgeekcode/dereinfo/SongRecyclerViewAdapter.kt
+++ b/app/src/main/java/com/kyhsgeekcode/dereinfo/SongRecyclerViewAdapter.kt
@@ -31,6 +31,7 @@ class SongRecyclerViewAdapter(
     private val values: MutableList<MusicInfo> = ArrayList()
     private var filteredItemList: MutableList<MusicInfo> = values
     var currentDifficulty: TW5Difficulty = TW5Difficulty.Master
+    var listView: RecyclerView? = null
 
     init {
         onClickListener = View.OnClickListener { v ->
@@ -60,6 +61,7 @@ class SongRecyclerViewAdapter(
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
         val view = LayoutInflater.from(parent.context)
             .inflate(R.layout.song_list_content, parent, false)
+        listView = parent as RecyclerView
         return ViewHolder(view)
     }
 
@@ -78,28 +80,41 @@ class SongRecyclerViewAdapter(
         }
         val statistic = DereDatabaseHelper.theInstance.musicInfoIDToStatistic[item.id]
         val currentStatistic = statistic?.get(currentDifficulty)
-        Log.d(TAG,"statistic:${currentStatistic.toString()}")
+        Log.d(TAG, "statistic:${currentStatistic.toString()}")
         with(holder) {
             if (currentStatistic != null) {
                 tvLevel.text = """lv.${currentStatistic[StatisticIndex.Level]?.toInt() ?: "??"}"""
-                tvConditionValue.text = currentStatistic[sortType.getStatisticIndex()]?.formatCleanPercent(2)
+                tvConditionValue.text =
+                    currentStatistic[sortType.getStatisticIndex()]?.formatCleanPercent(2)
             } else {
                 tvLevel.text = "-"
                 tvConditionValue.text = "-"
             }
             for (button in layoutDifficulties.children) {
                 if (button is Button) {
+                    val btnDifficulty = TW5Difficulty.fromString(button.text.toString())
                     button.isEnabled =
-                        statistic?.containsKey(TW5Difficulty.fromString(button.text.toString())) == true
-                    button.setOnClickListener{
-                        if(twoPaneInTablet) {
+                        statistic?.containsKey(btnDifficulty) == true
+                    button.setOnClickListener {
+                        currentMusicIDIndex = item.id
+                        if (twoPaneInTablet) {
                             //display
                         } else {
-                            currentDifficulty = TW5Difficulty.fromString(button.text.toString())
+                            currentDifficulty = btnDifficulty
                         }
                         sortBy(sortType)
                         notifyDataSetChanged()
+                        scrollToIndex()
                     }
+                    if (button.isEnabled) {
+                        if (currentDifficulty == btnDifficulty) {
+                            button.setBackgroundResource(R.drawable.shape_gradient_selected)
+                        } else {
+                            button.setBackgroundResource(R.drawable.shape_gradient_round)
+                        }
+                    } else
+                        button.setBackgroundResource(R.drawable.shape_gradient_disabled)
+
                 }
             }
         }
@@ -109,6 +124,14 @@ class SongRecyclerViewAdapter(
 
     override fun getItemCount() = filteredItemList.size
 
+    fun scrollToIndex() {
+        val realIndex = filteredItemList.indexOfFirst {
+            it.id == currentMusicIDIndex
+        }
+        if (realIndex in 0..filteredItemList.size)
+            listView?.scrollToPosition(realIndex)
+    }
+
     fun clear() {
         values.clear()
         filteredItemList.clear()
@@ -208,11 +231,13 @@ class SongRecyclerViewAdapter(
     fun sortBy(sortType: SortType) {
         this.sortType = sortType
         filteredItemList.sortByDescending {
-            sortType.condition(it,currentDifficulty) as Comparable<Any>
+            sortType.condition(it, currentDifficulty) as Comparable<Any>
         }
         notifyDataSetChanged()
+        scrollToIndex()
     }
 
     var userFilter: SongFilter = SongFilter()
     var sortType: SortType = SortType.Alphabetical
+    var currentMusicIDIndex : Int = 0
 }
diff --git a/app/src/main/res/drawable/shape_gradient_disabled.xml b/app/src/main/res/drawable/shape_gradient_disabled.xml
new file mode 100644
index 0000000..897c8f4
--- /dev/null
+++ b/app/src/main/res/drawable/shape_gradient_disabled.xml
@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <gradient
+        android:endColor="@color/gray"
+        android:gradientRadius="30dp"
+        android:startColor="@color/dkgray"
+        android:type="radial" />
+    <corners android:radius="@dimen/btn_corner_radius" />
+    <stroke
+        android:color="@android:color/black"
+        android:width="0dp" />
+</shape>
+
diff --git a/app/src/main/res/drawable/shape_gradient_round.xml b/app/src/main/res/drawable/shape_gradient_round.xml
new file mode 100644
index 0000000..15a7bd0
--- /dev/null
+++ b/app/src/main/res/drawable/shape_gradient_round.xml
@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+<gradient
+    android:endColor="@color/gray"
+    android:gradientRadius="30dp"
+    android:startColor="@color/white"
+    android:type="radial" />
+<corners android:radius="@dimen/btn_corner_radius" />
+<stroke
+    android:color="@android:color/black"
+    android:width="0dp" />
+</shape>
+
diff --git a/app/src/main/res/drawable/shape_gradient_selected.xml b/app/src/main/res/drawable/shape_gradient_selected.xml
new file mode 100644
index 0000000..6f147c5
--- /dev/null
+++ b/app/src/main/res/drawable/shape_gradient_selected.xml
@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <gradient
+        android:endColor="@color/green"
+        android:gradientRadius="30dp"
+        android:startColor="@color/white"
+        android:type="radial" />
+    <corners android:radius="@dimen/btn_corner_radius" />
+    <stroke
+        android:color="@android:color/white"
+        android:width="1dp" />
+</shape>
+
diff --git a/app/src/main/res/layout/song_list_content.xml b/app/src/main/res/layout/song_list_content.xml
index 1f711a9..22c7baf 100644
--- a/app/src/main/res/layout/song_list_content.xml
+++ b/app/src/main/res/layout/song_list_content.xml
@@ -62,6 +62,7 @@
             android:id="@+id/buttonDebut"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Debut"
             app:layout_constraintEnd_toStartOf="@id/buttonRegular"
             app:layout_constraintStart_toStartOf="parent"
@@ -71,6 +72,7 @@
             android:id="@+id/buttonRegular"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Regular"
             app:layout_constraintEnd_toStartOf="@id/buttonPro"
             app:layout_constraintStart_toEndOf="@id/buttonDebut"
@@ -80,6 +82,7 @@
             android:id="@+id/buttonPro"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Pro"
             app:layout_constraintEnd_toStartOf="@id/buttonMaster"
             app:layout_constraintStart_toEndOf="@id/buttonRegular"
@@ -89,6 +92,7 @@
             android:id="@+id/buttonMaster"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Master"
             app:layout_constraintEnd_toStartOf="@id/buttonMasterPlus"
             app:layout_constraintStart_toEndOf="@id/buttonPro"
@@ -98,6 +102,7 @@
             android:id="@+id/buttonMasterPlus"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Master+"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toEndOf="@id/buttonMaster"
@@ -107,6 +112,7 @@
             android:id="@+id/buttonLight"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Light"
             app:layout_constraintEnd_toStartOf="@id/buttonTrick"
             app:layout_constraintStart_toStartOf="parent"
@@ -116,6 +122,7 @@
             android:id="@+id/buttonTrick"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Trick"
             app:layout_constraintEnd_toStartOf="@id/buttonPiano"
             app:layout_constraintStart_toEndOf="@id/buttonLight"
@@ -125,6 +132,7 @@
             android:id="@+id/buttonPiano"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Piano"
             app:layout_constraintEnd_toStartOf="@id/buttonForte"
             app:layout_constraintStart_toEndOf="@id/buttonTrick"
@@ -134,6 +142,7 @@
             android:id="@+id/buttonForte"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
+            android:background="@drawable/shape_gradient_round"
             android:text="Forte"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toEndOf="@id/buttonPiano"
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index 6b3f6ab..f952552 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -3,4 +3,10 @@
     <color name="colorPrimary">#008577</color>
     <color name="colorPrimaryDark">#00574B</color>
     <color name="colorAccent">#D81B60</color>
+    <color name="green">#53DE6A</color>
+    <color name="blue">#536ADE</color>
+    <color name="yellow">#FACC43</color>
+    <color name="gray">#BBBBBB</color>
+    <color name="white">#FFFFFF</color>
+    <color name="dkgray">#888888</color>
 </resources>
diff --git a/app/src/main/res/values/dimens.xml b/app/src/main/res/values/dimens.xml
index 4030240..f9702f5 100644
--- a/app/src/main/res/values/dimens.xml
+++ b/app/src/main/res/values/dimens.xml
@@ -8,4 +8,5 @@
     <dimen name="app_bar_height">200dp</dimen>
     <dimen name="item_width">200dp</dimen>
     <dimen name="text_margin">16dp</dimen>
+    <dimen name="btn_corner_radius">8dp</dimen>
 </resources>