diff --git a/display/display-code.c b/display/display-code.c
index d9ceb58f..23abaa2e 100644
--- a/display/display-code.c
+++ b/display/display-code.c
@@ -346,6 +346,7 @@ void display_composit(struct display* display, struct framebuffer fb)
 	switch ( display->mouse_state )
 	{
 	case MOUSE_STATE_NONE: break;
+	case MOUSE_STATE_BUTTON_PRESS: break;
 	case MOUSE_STATE_TITLE_MOVE: break;
 	case MOUSE_STATE_RESIZE_BOTTOM: cursor_text = "↓"; break;
 	case MOUSE_STATE_RESIZE_BOTTOM_LEFT: cursor_text = "└"; break;
@@ -653,34 +654,83 @@ void display_mouse_event(struct display* display, uint8_t byte)
 	ssize_t window_pointer_x = display->pointer_x - window->left;
 	ssize_t window_pointer_y = display->pointer_y - window->top;
 
+	if ( display->active_window != window )
+	{
+		if ( bytes[0] & (MOUSE_BUTTON_LEFT | MOUSE_BUTTON_MIDDLE |
+		                 MOUSE_BUTTON_RIGHT) )
+		{
+			// TODO: Exit mouse from the current window.
+			display_set_active_window(display, window);
+		}
+		else
+			return;
+	}
+
+	size_t border_width = window_border_width(window);
+	size_t button_width = FONT_WIDTH * 2;
+	ssize_t buttons_x = window->width - border_width
+	                  - button_width * 3 + 1;
+	size_t tt_height = FONT_HEIGHT;
+	size_t tt_pos_y = (TITLE_HEIGHT - FONT_HEIGHT) / 2 + 2;
+
+	bool mouse_on_title = 0 <= window_pointer_x &&
+	                      window_pointer_x < (ssize_t) window->width &&
+	                      0 <= window_pointer_y &&
+	                      window_pointer_y <= (ssize_t) TITLE_HEIGHT;
+
+	for ( size_t n = 0; n < 3; n++ )
+	{
+		if ( (ssize_t) tt_pos_y <= window_pointer_y &&
+		     window_pointer_y <= (ssize_t) (tt_height + tt_pos_y) &&
+			 (ssize_t) (button_width * n) <= window_pointer_x - buttons_x &&
+			 window_pointer_x - buttons_x < (ssize_t) (button_width * (n + 1)) )
+		{
+			if ( display->mouse_state == MOUSE_STATE_NONE &&
+			     (bytes[0] & MOUSE_BUTTON_LEFT) )
+			{
+				display->mouse_state = MOUSE_STATE_BUTTON_PRESS;
+				window->button_states[n] = BUTTON_STATE_PRESSED;
+				window_render_frame(window);
+			}
+			else if ( display->mouse_state == MOUSE_STATE_BUTTON_PRESS &&
+			          window->button_states[n] == BUTTON_STATE_PRESSED )
+			{
+				window->button_states[n] = BUTTON_STATE_NORMAL;
+				window_render_frame(window);
+				switch ( n )
+				{
+				case 0: /* TODO: Minimize. */ break;
+				case 1: window_toggle_maximized(window); break;
+				case 2: window_quit(window); break;
+				}
+				return;
+			}
+			else if ( display->mouse_state == MOUSE_STATE_NONE &&
+			          window->button_states[n] != BUTTON_STATE_HOVER )
+			{
+				window->button_states[n] = BUTTON_STATE_HOVER;
+				window_render_frame(window);
+			}
+		}
+		else if ( window->button_states[n] != BUTTON_STATE_NORMAL )
+		{
+			window->button_states[n] = BUTTON_STATE_NORMAL;
+			display->mouse_state = MOUSE_STATE_NONE;
+			window_render_frame(window);
+		}
+	}
+
 	if ( bytes[0] & MOUSE_BUTTON_LEFT )
 	{
-		display_set_active_window(display, window);
 		if ( display->mouse_state == MOUSE_STATE_NONE )
 		{
 			// TODO: Stay in state until mouse release.
-			if ( display->key_lalt ||
-			     (0 <= window_pointer_x &&
-			      window_pointer_x < (ssize_t) window->width &&
-			      0 <= window_pointer_y &&
-			      window_pointer_y <= (ssize_t) TITLE_HEIGHT) )
+			if ( display->key_lalt || mouse_on_title )
 			{
-				size_t border_width = window_border_width(window);
-				size_t button_width = FONT_WIDTH * 2;
-				ssize_t buttons_x = window->width - border_width
-				                  - button_width * 3 + 1;
-				ssize_t rel_x = window_pointer_x - buttons_x;
-				if ( 0 <= rel_x && rel_x < (ssize_t) button_width )
-				{
-					// TODO Minimize window.
-				}
-				else if ( 0 <= rel_x && rel_x < (ssize_t) button_width * 2 )
-					window_toggle_maximized(window);
-				else if ( 0 <= rel_x && rel_x < (ssize_t) button_width * 3 )
-					window_quit(window);
-				else
+				if ( window_pointer_x < buttons_x || !mouse_on_title )
 					display->mouse_state = MOUSE_STATE_TITLE_MOVE;
-			} else if ( window_pointer_x < 0 && window_pointer_y < 0 )
+			}
+			else if ( window_pointer_x < 0 && window_pointer_y < 0 )
 				display->mouse_state = MOUSE_STATE_RESIZE_TOP_LEFT;
 			else if ( window_pointer_x < 0 &&
 			          0 <= window_pointer_y &&
@@ -719,6 +769,7 @@ void display_mouse_event(struct display* display, uint8_t byte)
 			switch ( display->mouse_state )
 			{
 			case MOUSE_STATE_NONE: break;
+			case MOUSE_STATE_BUTTON_PRESS: break;
 			case MOUSE_STATE_TITLE_MOVE:
 				if ( clipped_edge )
 				{
diff --git a/display/display.h b/display/display.h
index 9b3c9b5f..d0f0d5d9 100644
--- a/display/display.h
+++ b/display/display.h
@@ -32,6 +32,7 @@
 enum mouse_state
 {
 	MOUSE_STATE_NONE,
+	MOUSE_STATE_BUTTON_PRESS,
 	MOUSE_STATE_TITLE_MOVE,
 	MOUSE_STATE_RESIZE_BOTTOM,
 	MOUSE_STATE_RESIZE_BOTTOM_LEFT,
diff --git a/display/window.c b/display/window.c
index e6715b40..3c31e6d8 100644
--- a/display/window.c
+++ b/display/window.c
@@ -56,6 +56,8 @@ void window_render_frame(struct window* window)
 	                                 : make_color_a(180, 180, 255, 128);
 	uint32_t title_color = has_focus ? make_color_a(16, 16, 16, 240)
 	                                 : make_color_a(32, 32, 32, 200);
+	uint32_t button_hover_glass = make_color_a(220, 220, 255, 255);
+	uint32_t button_press_glass = make_color_a(180, 180, 255, 255);
 
 	size_t start_x = 0;
 	size_t start_y = 0;
@@ -125,6 +127,21 @@ void window_render_frame(struct window* window)
 		for (size_t y = 0; y < button_height; y++)
 			framebuffer_set_pixel(buttons_fb, button_width * 2 + x, y, 0xFF8080FF);
 #endif
+	for ( size_t n = 0; n < 3; n++ )
+	{
+		uint32_t color = glass_color;
+		switch ( window->button_states[n] )
+		{
+		case BUTTON_STATE_NORMAL: continue;
+		case BUTTON_STATE_HOVER: color = button_hover_glass; break;
+		case BUTTON_STATE_PRESSED: color = button_press_glass; break;
+		}
+		size_t bx = button_width * n;
+		size_t by = 0;
+		for ( size_t y = 0; y < tt_height; y++ )
+			for ( size_t x = 0; x < button_width; x++ )
+				framebuffer_set_pixel(buttons_fb, bx + x, by + y, color);
+	}
 	for ( size_t i = 0; i < button_size; i++ )
 	{
 		size_t bx = button_width * 0 + (button_width - button_size) / 2;
diff --git a/display/window.h b/display/window.h
index c8dd8241..5c9c205f 100644
--- a/display/window.h
+++ b/display/window.h
@@ -35,6 +35,13 @@ static const size_t BORDER_WIDTH = 8;
 static const size_t TITLE_HEIGHT = 28;
 static const size_t RESIZE_GRACE = 16;
 
+enum button_state
+{
+	BUTTON_STATE_NORMAL,
+	BUTTON_STATE_HOVER,
+	BUTTON_STATE_PRESSED,
+};
+
 enum window_state
 {
 	WINDOW_STATE_REGULAR,
@@ -68,6 +75,7 @@ struct window
 	size_t saved_height;
 	uint32_t window_id;
 	enum window_state window_state;
+	enum button_state button_states[3];
 	bool created;
 	bool show;
 	bool focus;