diff --git a/internal/board/graphics/cell.go b/internal/board/graphics/cell.go
index fc40769..e828004 100644
--- a/internal/board/graphics/cell.go
+++ b/internal/board/graphics/cell.go
@@ -78,3 +78,15 @@ func (tc *TaggedCell) Is(key string, value string) bool {
 		return false
 	}
 }
+
+func (tc *TaggedCell) Match(tags map[string]string) bool {
+	if tags == nil {
+		return false
+	}
+	for k, v := range tags {
+		if tc.Is(k, v) {
+			return true
+		}
+	}
+	return false
+}
diff --git a/internal/board/graphics/lines.go b/internal/board/graphics/lines.go
index fe14502..42894db 100644
--- a/internal/board/graphics/lines.go
+++ b/internal/board/graphics/lines.go
@@ -46,18 +46,15 @@ func (l *LineStack) add(cell *LinesCell) {
 }
 
 func areCrossing(first *LinesCell, last *LinesCell) bool {
-	if first != nil && last != nil {
-		if last.l && last.r && !last.t && !last.b {
-			if !first.l && !first.r && first.t && first.b {
-				// lines have crossed.
-				return true
-			}
-		} else if !last.l && !last.r && last.t && last.b {
-			if first.l && first.r && !first.t && !first.b {
-				// lines have crossed.
-				return true
-			}
-		}
+	if first == nil || last == nil {
+		return false
+	}
+	if hashLines(first) == 0b_0101 && hashLines(last) == 0b_1010 {
+		// lines have crossed.
+		return true
+	} else if hashLines(last) == 0b_0101 && hashLines(first) == 0b_1010 {
+		// lines have crossed.
+		return true
 	}
 	return false
 }
diff --git a/internal/board/graphics/lines_test.go b/internal/board/graphics/lines_test.go
index 31db15a..ad90c26 100644
--- a/internal/board/graphics/lines_test.go
+++ b/internal/board/graphics/lines_test.go
@@ -34,5 +34,5 @@ func TestLineStack_Render_Crossed_2(t *testing.T) {
 	lineStack.add(&LinesCell{l: true, r: true})
 	a.Equal('┴', lineStack.Render())
 	lineStack.add(&LinesCell{t: true, b: true})
-	a.Equal('┼', lineStack.Render())
+	a.Equal('│', lineStack.Render())
 }
diff --git a/internal/board/graphics/matrix.go b/internal/board/graphics/matrix.go
index c89e655..ac3d798 100644
--- a/internal/board/graphics/matrix.go
+++ b/internal/board/graphics/matrix.go
@@ -102,7 +102,7 @@ func (m *Matrix) Render() string {
 	rendered := ""
 	for j := 0; j < m.h; j++ {
 		for i := 0; i < m.w; i++ {
-			rendered += string(m.elements[j][i].Render())
+			rendered += string(m.elements[j][i].Render(nil))
 		}
 		rendered += "\n"
 	}
diff --git a/internal/board/graphics/stack.go b/internal/board/graphics/stack.go
index 21d8658..0f9011a 100644
--- a/internal/board/graphics/stack.go
+++ b/internal/board/graphics/stack.go
@@ -33,6 +33,18 @@ func (cs *CellStack) Is(key string, value string) bool {
 	return false
 }
 
+func (cs *CellStack) Match(tags map[string]string) bool {
+	if tags == nil {
+		return false
+	}
+	for k, v := range tags {
+		if cs.Is(k, v) {
+			return true
+		}
+	}
+	return false
+}
+
 func (cs *CellStack) PlaceChar(char rune) *TaggedCell {
 	charTaggedCell := NewTaggedCell(CharCell(char))
 	cs.add(charTaggedCell)
@@ -56,10 +68,22 @@ var arrowMap = map[bool]rune{
 	false: '▷',
 }
 
-func (cs *CellStack) Render() rune {
+func (cs *CellStack) Render(
+	priorityTags map[string]string,
+) rune {
 	lineStack := LineStack{}
+	priorityCellStack := *cs
+
+	if cs.Match(priorityTags) {
+		priorityCellStack = CellStack{}
+		for _, cell := range *cs {
+			if cell.Match(priorityTags) {
+				priorityCellStack.add(cell)
+			}
+		}
+	}
 
-	for _, taggedCell := range *cs {
+	for _, taggedCell := range priorityCellStack {
 		switch cell := taggedCell.Cell.(type) {
 		case EmptyCell:
 			// nothing.
diff --git a/internal/board/graphics/stack_test.go b/internal/board/graphics/stack_test.go
index 1fac049..7a6f132 100644
--- a/internal/board/graphics/stack_test.go
+++ b/internal/board/graphics/stack_test.go
@@ -15,7 +15,21 @@ func TestCellStack_Render_lines(t *testing.T) {
 	cs.add(NewTaggedCell(&LinesCell{
 		b: true,
 	}))
-	a.Equal('│', cs.Render())
+	a.Equal('│', cs.Render(nil))
+}
+
+func TestCellStack_Render_linesPriority(t *testing.T) {
+	a := require.New(t)
+	cs := CellStack{}
+	cs.add(NewTaggedCell(&LinesCell{
+		t: true,
+		r: true,
+	}))
+	cs.add(NewTaggedCell(&LinesCell{
+		l: true,
+		r: true,
+	}).WithTag("test", "true"))
+	a.Equal('─', cs.Render(map[string]string{"test": "true"}))
 }
 
 func TestCellStack_Render_charHasPriority(t *testing.T) {
@@ -25,7 +39,7 @@ func TestCellStack_Render_charHasPriority(t *testing.T) {
 		t: true,
 	}))
 	cs.PlaceChar('a')
-	a.Equal('a', cs.Render())
+	a.Equal('a', cs.Render(nil))
 }
 
 func TestCellStack_Render_arrowHasPriority(t *testing.T) {
@@ -35,5 +49,5 @@ func TestCellStack_Render_arrowHasPriority(t *testing.T) {
 	cs.add(NewTaggedCell(&LinesCell{
 		t: true,
 	}))
-	a.Equal('▷', cs.Render())
+	a.Equal('▷', cs.Render(nil))
 }
diff --git a/internal/graph/.graph_test/Simple.txt b/internal/graph/.graph_test/Simple.txt
index cec8b6c..a13e05f 100755
--- a/internal/graph/.graph_test/Simple.txt
+++ b/internal/graph/.graph_test/Simple.txt
@@ -4,6 +4,6 @@
 │ │       
 ├─┼▷2     
 │ │ │     
-│ └─┼▷4◁─┐
+│ └─├▷4◁─┐
 │   │ │  │
 └───┴─┴▷3┘
diff --git a/internal/tui/tui.go b/internal/tui/tui.go
index 1514960..e9af042 100644
--- a/internal/tui/tui.go
+++ b/internal/tui/tui.go
@@ -43,7 +43,9 @@ func Loop(b *board.Board) error {
 				s.SetContent(
 					j,
 					i,
-					cells[i][j].Render(),
+					cells[i][j].Render(map[string]string{
+						"nodeIndex": strconv.Itoa(state.selected),
+					}),
 					nil,
 					style,
 				)