diff --git a/grid_line.go b/grid_line.go
index 6fce265..fe49cba 100644
--- a/grid_line.go
+++ b/grid_line.go
@@ -1,5 +1,33 @@
 package chart
 
+// GenerateGridLines generates grid lines.
+func GenerateGridLines(ticks []Tick, isVertical bool) []GridLine {
+	var gl []GridLine
+	isMinor := false
+	minorStyle := Style{
+		StrokeColor: DefaultGridLineColor.WithAlpha(100),
+		StrokeWidth: 1.0,
+	}
+	majorStyle := Style{
+		StrokeColor: DefaultGridLineColor,
+		StrokeWidth: 1.0,
+	}
+	for _, t := range ticks {
+		s := majorStyle
+		if isMinor {
+			s = minorStyle
+		}
+		gl = append(gl, GridLine{
+			Style:      s,
+			IsMinor:    isMinor,
+			IsVertical: isVertical,
+			Value:      t.Value,
+		})
+		isMinor = !isMinor
+	}
+	return gl
+}
+
 // GridLine is a line on a graph canvas.
 type GridLine struct {
 	IsMinor    bool
diff --git a/testserver/main.go b/testserver/main.go
index 269d596..3918733 100644
--- a/testserver/main.go
+++ b/testserver/main.go
@@ -46,12 +46,6 @@ func chartHandler(rc *web.RequestContext) web.ControllerResult {
 			Style: chart.Style{
 				Show: true,
 			},
-			GridMajorStyle: chart.Style{
-				Show: true,
-			},
-			GridMinorStyle: chart.Style{
-				Show: true,
-			},
 		},
 		YAxis: chart.YAxis{
 			Style: chart.Style{
@@ -64,7 +58,7 @@ func chartHandler(rc *web.RequestContext) web.ControllerResult {
 				},
 			},
 			GridMajorStyle: chart.Style{
-				Show: true,
+				Show: false,
 			},
 			GridMinorStyle: chart.Style{
 				Show: true,
@@ -75,12 +69,16 @@ func chartHandler(rc *web.RequestContext) web.ControllerResult {
 				Name:    "a",
 				XValues: s1x,
 				YValues: s1y,
+				Style: chart.Style{
+					Show:      true,
+					FillColor: chart.GetDefaultSeriesStrokeColor(0).WithAlpha(64),
+				},
 			},
 			chart.AnnotationSeries{
 				Name: fmt.Sprintf("%s - Last Value", "Test"),
 				Style: chart.Style{
 					Show:        true,
-					StrokeColor: chart.DefaultSeriesStrokeColors[0],
+					StrokeColor: chart.GetDefaultSeriesStrokeColor(0),
 				},
 				Annotations: []chart.Annotation{
 					chart.Annotation{
diff --git a/yaxis.go b/yaxis.go
index 2dc9439..4213875 100644
--- a/yaxis.go
+++ b/yaxis.go
@@ -71,33 +71,7 @@ func (ya YAxis) GetGridLines(ticks []Tick) []GridLine {
 	if len(ya.GridLines) > 0 {
 		return ya.GridLines
 	}
-	return ya.generateGridLines(ticks)
-}
-
-func (ya YAxis) generateGridLines(ticks []Tick) []GridLine {
-	var gl []GridLine
-	isMinor := false
-	minorStyle := Style{
-		StrokeColor: DefaultGridLineColor.WithAlpha(100),
-		StrokeWidth: 1.0,
-	}
-	majorStyle := Style{
-		StrokeColor: DefaultGridLineColor,
-		StrokeWidth: 1.0,
-	}
-	for _, t := range ticks {
-		s := majorStyle
-		if isMinor {
-			s = minorStyle
-		}
-		gl = append(gl, GridLine{
-			Style:   s,
-			IsMinor: isMinor,
-			Value:   t.Value,
-		})
-		isMinor = !isMinor
-	}
-	return gl
+	return GenerateGridLines(ticks, false)
 }
 
 // Measure returns the bounds of the axis.