Adjust FilterControl to match design and give an absolute height.

osu.Game/Screens/Select/FilterControl.cs

@@ -27,14 +27,12 @@ namespace osu.Game.Screens.Select
 
         public FilterControl()
         {
-            AutoSizeAxes = Axes.Y;
-
             Children = new Drawable[]
             {
                 new Box
                 {
                     Colour = Color4.Black,
-                    Alpha = 0.6f,
+                    Alpha = 0.8f,
                     RelativeSizeAxes = Axes.Both,
                 },
                 new FlowContainer

osu.Game/Screens/Select/PlaySongSelect.cs

@@ -26,7 +26,6 @@ using osu.Game.Graphics.Containers;
 using osu.Game.Graphics;
 using osu.Framework.Input;
 using OpenTK.Input;
-using osu.Game.Graphics;
 using System.Collections.Generic;
 using osu.Framework.Threading;
 
@@ -112,6 +111,7 @@ namespace osu.Game.Screens.Select
                 filter = new FilterControl
                 {
                     RelativeSizeAxes = Axes.X,
+                    Height = 100,
                     FilterChanged = filterChanged,
                     Exit = Exit,
                 },