diff --git a/pkg/internal/config/const.go b/pkg/internal/config/const.go
new file mode 100644
index 0000000..d912156
--- /dev/null
+++ b/pkg/internal/config/const.go
@@ -0,0 +1 @@
+package config
diff --git a/pkg/internal/land/object_interactable.go b/pkg/internal/land/object_interactable.go
index c1f60ba..48df4e2 100644
--- a/pkg/internal/land/object_interactable.go
+++ b/pkg/internal/land/object_interactable.go
@@ -1,7 +1,15 @@
 package land
 
+type UserEventType = int
+
+const (
+	UserEventMouseDown = UserEventType(iota)
+	UserEventMouseUp
+	UserEventMouseMove
+)
+
 type InteractableObject interface {
 	GetPosition() Vector2D
 	GetSize() Vector2D
-	OnClick(mousePos Vector2D)
+	OnEvent(event UserEventType, args ...any)
 }
diff --git a/pkg/internal/land/object_ui.go b/pkg/internal/land/object_ui.go
index ae121d8..eea7506 100644
--- a/pkg/internal/land/object_ui.go
+++ b/pkg/internal/land/object_ui.go
@@ -2,20 +2,20 @@ package land
 
 import "github.com/veandco/go-sdl2/sdl"
 
-type BaseUIObject struct {
+type BaseWidget struct {
 	BaseObject
 
 	Position Vector2D
 	Size     Vector2D
 }
 
-func (p *BaseUIObject) Draw(pen *sdl.Renderer) {
+func (p *BaseWidget) Draw(pen *sdl.Renderer) {
 }
 
-func (p *BaseUIObject) GetPosition() Vector2D {
+func (p *BaseWidget) GetPosition() Vector2D {
 	return p.Position
 }
 
-func (p *BaseUIObject) GetSize() Vector2D {
+func (p *BaseWidget) GetSize() Vector2D {
 	return p.Size
 }
diff --git a/pkg/internal/land/renderer/curve.go b/pkg/internal/land/renderer/curve.go
new file mode 100644
index 0000000..e341f22
--- /dev/null
+++ b/pkg/internal/land/renderer/curve.go
@@ -0,0 +1,10 @@
+package renderer
+
+import (
+	"github.com/veandco/go-sdl2/gfx"
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+func FillRoundedRect(pen *sdl.Renderer, rect *sdl.Rect, color sdl.Color, radius int32) {
+	gfx.RoundedRectangleColor(pen, rect.X, rect.Y, rect.X+rect.W, rect.Y+rect.H, radius, color)
+}
diff --git a/pkg/internal/land/root.go b/pkg/internal/land/root.go
index 364950b..510849b 100644
--- a/pkg/internal/land/root.go
+++ b/pkg/internal/land/root.go
@@ -51,18 +51,28 @@ func (p *RootObject) ForEachChildren(cb func(child Object)) {
 func (p *RootObject) HandleUserEvent(event sdl.Event) {
 	switch event := event.(type) {
 	case *sdl.MouseButtonEvent:
-		if event.Type == sdl.MOUSEBUTTONDOWN {
-			x, y := float64(event.X), float64(event.Y)
-			vec := Vector2D{x, y}
-			p.ForEachChildren(func(child Object) {
-				if interChild, ok := child.(InteractableObject); ok {
-					isOverlap := IsOverlapWithPoint(child.(PositionedObject), vec)
-					if isOverlap {
-						interChild.OnClick(vec)
+		x, y := float64(event.X), float64(event.Y)
+		vec := Vector2D{x, y}
+		p.ForEachChildren(func(child Object) {
+			if interChild, ok := child.(InteractableObject); ok {
+				if IsOverlapWithPoint(child.(PositionedObject), vec) {
+					if event.Type == sdl.MOUSEBUTTONDOWN {
+						interChild.OnEvent(UserEventMouseDown, vec)
+					} else if event.Type == sdl.MOUSEBUTTONUP {
+						interChild.OnEvent(UserEventMouseUp, vec)
 					}
 				}
-			})
-		}
+			}
+		})
+	case *sdl.MouseMotionEvent:
+		x, y := float64(event.X), float64(event.Y)
+		vec := Vector2D{x, y}
+		p.ForEachChildren(func(child Object) {
+			if interChild, ok := child.(InteractableObject); ok {
+				isOverlap := IsOverlapWithPoint(child.(PositionedObject), vec)
+				interChild.OnEvent(UserEventMouseMove, vec, isOverlap)
+			}
+		})
 	}
 }
 
diff --git a/pkg/internal/land/ui/button.go b/pkg/internal/land/ui/button.go
index a301674..72bc250 100644
--- a/pkg/internal/land/ui/button.go
+++ b/pkg/internal/land/ui/button.go
@@ -2,36 +2,51 @@ package ui
 
 import (
 	"git.solsynth.dev/highland/codingland/pkg/internal/land"
+	"git.solsynth.dev/highland/codingland/pkg/internal/land/renderer"
 	"github.com/veandco/go-sdl2/sdl"
 	"github.com/veandco/go-sdl2/ttf"
 	"log"
 )
 
-type ButtonObject struct {
-	land.BaseUIObject
+type ButtonWidget struct {
+	land.BaseWidget
 
-	Label        string
-	Font         *ttf.Font
-	OnClickEvent func(mousePos land.Vector2D)
+	Label   string
+	Font    *ttf.Font
+	OnClick func(mousePos land.Vector2D)
+
+	isHovering bool
+	isClicking bool
 }
 
-func (p *ButtonObject) Draw(pen *sdl.Renderer) {
+func (p *ButtonWidget) Draw(pen *sdl.Renderer) {
+	var borderColor, bgColor sdl.Color
+	if p.isClicking {
+		borderColor = sdl.Color{R: 200, G: 0, B: 0, A: 255}
+		bgColor = sdl.Color{R: 255, G: 0, B: 0, A: 255}
+	} else if p.isHovering {
+		borderColor = sdl.Color{R: 0, G: 200, B: 0, A: 255}
+		bgColor = sdl.Color{R: 0, G: 255, B: 0, A: 255}
+	} else {
+		borderColor = sdl.Color{R: 255, G: 255, B: 255, A: 255}
+		bgColor = sdl.Color{R: 0, G: 0, B: 0, A: 255}
+	}
+
 	var borderWidth int32 = 2
 
-	pen.SetDrawColor(255, 255, 255, 255)
-	pen.FillRect(&sdl.Rect{
+	pen.SetDrawColor(borderColor.R, borderColor.G, borderColor.B, borderColor.A)
+	renderer.FillRoundedRect(pen, &sdl.Rect{
 		X: int32(p.Position.X),
 		Y: int32(p.Position.Y),
 		W: int32(p.Size.X),
 		H: int32(p.Size.Y),
-	})
-	pen.SetDrawColor(0, 0, 0, 255)
-	pen.FillRect(&sdl.Rect{
+	}, borderColor, 16)
+	renderer.FillRoundedRect(pen, &sdl.Rect{
 		X: int32(p.Position.X) + borderWidth/2,
 		Y: int32(p.Position.Y) + borderWidth/2,
 		W: int32(p.Size.X) - borderWidth,
 		H: int32(p.Size.Y) - borderWidth,
-	})
+	}, bgColor, 16)
 
 	surface, err := p.Font.RenderUTF8Blended(p.Label, sdl.Color{R: 255, G: 255, B: 255, A: 255})
 	if err != nil {
@@ -47,15 +62,22 @@ func (p *ButtonObject) Draw(pen *sdl.Renderer) {
 	}
 	defer texture.Destroy()
 
-	textRect := sdl.Rect{
-		X: int32(p.BaseUIObject.Position.X),
-		Y: int32(p.BaseUIObject.Position.Y),
-		W: surface.W,
-		H: surface.H,
-	}
+	textWidth := surface.W
+	textHeight := surface.H
+	textX := int32(p.BaseWidget.Position.X) + (int32(p.BaseWidget.Size.X)-textWidth)/2
+	textY := int32(p.BaseWidget.Position.Y) + (int32(p.BaseWidget.Size.Y)-textHeight)/2
+	textRect := sdl.Rect{X: textX, Y: textY, W: textWidth, H: textHeight}
 	pen.Copy(texture, nil, &textRect)
 }
 
-func (p *ButtonObject) OnClick(mousePos land.Vector2D) {
-	p.OnClickEvent(mousePos)
+func (p *ButtonWidget) OnEvent(event land.UserEventType, args ...any) {
+	switch event {
+	case land.UserEventMouseDown:
+		p.isClicking = true
+		p.OnClick(args[0].(land.Vector2D))
+	case land.UserEventMouseUp:
+		p.isClicking = false
+	case land.UserEventMouseMove:
+		p.isHovering = args[1].(bool)
+	}
 }
diff --git a/pkg/internal/land/vector2d.go b/pkg/internal/land/vector2d.go
index f414ddd..2c01c9d 100644
--- a/pkg/internal/land/vector2d.go
+++ b/pkg/internal/land/vector2d.go
@@ -1,6 +1,8 @@
 package land
 
-import "fmt"
+import (
+	"fmt"
+)
 
 type Vector2D struct {
 	X, Y float64
diff --git a/pkg/internal/tiles/tile.go b/pkg/internal/tiles/tile.go
index 7a743c6..1b8ea92 100644
--- a/pkg/internal/tiles/tile.go
+++ b/pkg/internal/tiles/tile.go
@@ -40,6 +40,8 @@ func (p *Tile) GetSize() land.Vector2D {
 func (p *Tile) OnCollide(other land.CollidableObject) {
 }
 
-func (p *Tile) OnClick(mousePos land.Vector2D) {
-	log.Printf("user clicked tile: %s", mousePos.String())
+func (p *Tile) OnEvent(event land.UserEventType, args ...any) {
+	if event == land.UserEventMouseDown {
+		log.Printf("user clicked tile: %s", args[0].(land.Vector2D).String())
+	}
 }
diff --git a/pkg/main.go b/pkg/main.go
index 31a93c4..a682656 100644
--- a/pkg/main.go
+++ b/pkg/main.go
@@ -45,26 +45,15 @@ func main() {
 	}
 	defer renderer.Destroy()
 
-	sdl.SetHint(sdl.HINT_RENDER_SCALE_QUALITY, "1")
-
-	font, err := ttf.OpenFont("assets/fonts/NotoSans.ttf", 12)
+	font, err := ttf.OpenFont("assets/fonts/NotoSans.ttf", 14)
 	if err != nil {
 		log.Fatalf("Failed to open font: %s", err)
+	} else {
+		font.SetStyle(ttf.STYLE_BOLD)
 	}
 	defer font.Close()
 
 	root := land.NewRootObject()
-	root.AddChild(&ui.ButtonObject{
-		BaseUIObject: land.BaseUIObject{
-			Position: land.Vector2D{X: windowWidth/2 - 60, Y: windowHeight/2 - 25},
-			Size:     land.Vector2D{X: 120, Y: 50},
-		},
-		Label: "Hello, World!",
-		Font:  font,
-		OnClickEvent: func(_ land.Vector2D) {
-			sdl.ShowSimpleMessageBox(sdl.MESSAGEBOX_INFORMATION, "You clicked me!", "你惊扰了古希腊掌控按钮的神", window)
-		},
-	})
 	root.AddChild(&entities.Player{
 		Position: land.Vector2D{X: windowWidth/2 - 25, Y: windowHeight/2 - 25},
 		Size:     land.Vector2D{X: 50, Y: 50},
@@ -73,6 +62,17 @@ func main() {
 		Position: land.Vector2D{X: 50, Y: 50},
 		Size:     land.Vector2D{X: 50, Y: 50},
 	})
+	root.AddChild(&ui.ButtonWidget{
+		BaseWidget: land.BaseWidget{
+			Position: land.Vector2D{X: windowWidth/2 - 60, Y: windowHeight/2 - 25},
+			Size:     land.Vector2D{X: 120, Y: 50},
+		},
+		Label: "Hello, World!",
+		Font:  font,
+		OnClick: func(_ land.Vector2D) {
+			log.Println("你惊扰了古希腊掌控按钮的神")
+		},
+	})
 
 	// 10ms delay use be 100tps average
 	go root.RunEventLoop(10 * time.Millisecond)
@@ -83,13 +83,15 @@ func main() {
 			switch event.(type) {
 			case *sdl.QuitEvent:
 				running = false
-			case *sdl.MouseButtonEvent:
+			default:
 				root.HandleUserEvent(event)
 			}
 		}
 
+		// Draw the entire object tree
 		root.Draw(renderer)
 
+		// Show on the screen
 		renderer.Present()
 	}
 }