diff --git a/MetaballsKit/PreferencesViewController.swift b/MetaballsKit/PreferencesViewController.swift
index b5532d0..d248bf1 100644
--- a/MetaballsKit/PreferencesViewController.swift
+++ b/MetaballsKit/PreferencesViewController.swift
@@ -26,6 +26,10 @@ public class PreferencesViewController: NSViewController {
                       tag: Int(ColorStyle.gradient2Horizontal.rawValue),
                       colorNames: [NSLocalizedString("Right", comment: "two color horizontal gradient, color 1"),
                                    NSLocalizedString("Left", comment: "two color horizontal gradient, color 2")]),
+            StyleItem(name: NSLocalizedString("Two Color Gradient — Vertical", comment: "two color vertical gradient menu item"),
+                      tag: Int(ColorStyle.gradient2Vertical.rawValue),
+                      colorNames: [NSLocalizedString("Top", comment: "two color vertical gradient, color 1"),
+                                   NSLocalizedString("Bottom", comment: "two color vertical gradient, color 2")]),
         ]
     }
 
@@ -252,7 +256,7 @@ class ParameterView: NSView {
     private func commonInit() {
         stackView.translatesAutoresizingMaskIntoConstraints = false
         stackView.orientation = .horizontal
-        stackView.spacing = 8
+        stackView.spacing = 12
         stackView.alignment = .centerY
         stackView.distribution = .fill
 
diff --git a/MetaballsKit/Shaders.metal b/MetaballsKit/Shaders.metal
index 3a09eb9..af9dc91 100644
--- a/MetaballsKit/Shaders.metal
+++ b/MetaballsKit/Shaders.metal
@@ -83,16 +83,22 @@ sampleToColorShader(RasterizerData in               [[stage_in]],
     const float target = parameters.target;
     const float feather = parameters.feather;
     const float sample = sampleAtPoint(in.position.xy, balls, parameters.numberOfBalls);
-    const float blend = in.position.x / parameters.size.x;
 
     float4 out;
     switch (parameters.colorStyle) {
         case SingleColor:
             out = singleColor(sample, target, feather, parameters.colors[0]);
             break;
-        case Gradient2Horizontal:
+        case Gradient2Horizontal: {
+            const float blend = in.position.x / parameters.size.x;
             out = gradient2(sample, target, feather, blend, parameters.colors[0], parameters.colors[1]);
             break;
+        }
+        case Gradient2Vertical: {
+            const float blend = in.position.y / parameters.size.y;
+            out = gradient2(sample, target, feather, blend, parameters.colors[0], parameters.colors[1]);
+            break;
+        }
     }
 
     return out;