diff --git a/src/components/fabric/QPolygon.js b/src/components/fabric/QPolygon.js
index a2a78fda..a499032f 100644
--- a/src/components/fabric/QPolygon.js
+++ b/src/components/fabric/QPolygon.js
@@ -25,9 +25,6 @@ export default class QPolygon extends fabric.Group {
     if (!options.fontSize) {
       throw new Error('Font size is required.')
     }
-    if (!canvas) {
-      throw new Error('Canvas is required.')
-    }
 
     const sortPoints = sortedPoints(points)
     const polygon = new fabric.Polygon(sortPoints, options)
@@ -647,25 +644,25 @@ export default class QPolygon extends fabric.Group {
 
     const realLine1 = new QLine(
       [lines[0].x1, lines[0].y1, vPoint1.x, vPoint1.y],
-      { fontSize: this.fontSize, stroke: 'black', strokeWidth: 1 },
+      { fontSize: this.fontSize, stroke: 'blue', strokeWidth: 1 },
       getRoofHypotenuse(lines[0].length / 2),
     )
 
     const realLine2 = new QLine(
       [lines[0].x2, lines[0].y2, vPoint1.x, vPoint1.y],
-      { fontSize: this.fontSize, stroke: 'black', strokeWidth: 1 },
+      { fontSize: this.fontSize, stroke: 'blue', strokeWidth: 1 },
       getRoofHypotenuse(lines[0].length / 2),
     )
 
     const realLine3 = new QLine(
       [lines[1].x1, lines[1].y1, vPoint2.x, vPoint2.y],
-      { fontSize: this.fontSize, stroke: 'black', strokeWidth: 1 },
+      { fontSize: this.fontSize, stroke: 'blue', strokeWidth: 1 },
       getRoofHypotenuse(lines[1].length / 2),
     )
 
     const realLine4 = new QLine(
       [lines[1].x2, lines[1].y2, vPoint2.x, vPoint2.y],
-      { fontSize: this.fontSize, stroke: 'black', strokeWidth: 1 },
+      { fontSize: this.fontSize, stroke: 'blue', strokeWidth: 1 },
       getRoofHypotenuse(lines[1].length / 2),
     )
 
@@ -674,7 +671,7 @@ export default class QPolygon extends fabric.Group {
       [vPoint1.x, vPoint1.y, centerPoint1.x, centerPoint1.y],
       {
         fontSize: this.fontSize,
-        stroke: 'black',
+        stroke: 'blue',
         strokeWidth: 1,
         strokeDashArray: [5, 5],
       },
@@ -686,7 +683,7 @@ export default class QPolygon extends fabric.Group {
       [vPoint2.x, vPoint2.y, centerPoint2.x, centerPoint2.y],
       {
         fontSize: this.fontSize,
-        stroke: 'black',
+        stroke: 'blue',
         strokeWidth: 1,
         strokeDashArray: [5, 5],
       },
@@ -698,7 +695,7 @@ export default class QPolygon extends fabric.Group {
       [lines2[0].x2, lines2[0].y2, ridgePoint1[2], ridgePoint1[3]],
       {
         fontSize: this.fontSize,
-        stroke: 'black',
+        stroke: 'blue',
         strokeWidth: 1,
       },
       getRoofHypotenuse(lines[0].length / 2),
@@ -709,7 +706,7 @@ export default class QPolygon extends fabric.Group {
       [lines2[1].x2, lines2[1].y2, ridgePoint2[2], ridgePoint2[3]],
       {
         fontSize: this.fontSize,
-        stroke: 'black',
+        stroke: 'blue',
         strokeWidth: 1,
       },
       getRoofHypotenuse(lines[1].length / 2),
@@ -718,14 +715,14 @@ export default class QPolygon extends fabric.Group {
     // 용마루
     const ridge1 = new QLine(ridgePoint1, {
       fontSize: this.fontSize,
-      stroke: 'black',
+      stroke: 'blue',
       strokeWidth: 1,
     })
 
     // 용마루
     const ridge2 = new QLine(ridgePoint2, {
       fontSize: this.fontSize,
-      stroke: 'black',
+      stroke: 'blue',
       strokeWidth: 1,
     })
 
@@ -733,7 +730,7 @@ export default class QPolygon extends fabric.Group {
       [ridgePoint1[2], ridgePoint1[3], ridgePoint2[2], ridgePoint2[3]],
       {
         fontSize: this.fontSize,
-        stroke: 'black',
+        stroke: 'blue',
         strokeWidth: 1,
       },
       Math.abs(realLine1.length - realLine3.length),