diff --git a/src/components/DrawingCanvas.js b/src/components/DrawingCanvas.js
index 2c4959a..625b866 100644
--- a/src/components/DrawingCanvas.js
+++ b/src/components/DrawingCanvas.js
@@ -1,59 +1,81 @@
 import React, { useRef, useState, useEffect } from 'react';
 import { ChromePicker } from 'react-color';
 
-const DrawingCanvas = ({ color, setColor, thickness, setThickness, history, setHistory }) => {
+// Drawing utilities
+const drawLine = (ctx, x1, y1, x2, y2, color, thickness) => {
+  ctx.beginPath();
+  ctx.moveTo(x1, y1);
+  ctx.lineTo(x2, y2);
+  ctx.strokeStyle = color || '#000000';
+  ctx.lineWidth = thickness || 2;
+  ctx.lineCap = 'round';
+  ctx.stroke();
+};
+
+const drawShape = (ctx, shape) => {
+  ctx.beginPath();
+  ctx.strokeStyle = shape.color || '#000000';
+  ctx.lineWidth = shape.thickness || 2;
+  ctx.lineCap = 'round';
+
+  if (shape.type === 'rectangle') {
+    ctx.rect(shape.x || 0, shape.y || 0, shape.width || 0, shape.height || 0);
+  } else if (shape.type === 'circle') {
+    ctx.arc(shape.x || 0, shape.y || 0, shape.radius || 0, 0, Math.PI * 2);
+  }
+
+  ctx.stroke();
+};
+
+const DrawingCanvas = () => {
   const canvasRef = useRef(null);
   const [isDrawing, setIsDrawing] = useState(false);
   const [currentTool, setCurrentTool] = useState('pencil');
+  const [color, setColor] = useState('#000000');
+  const [thickness, setThickness] = useState(2);
+  const [history, setHistory] = useState([]);
   const [shapes, setShapes] = useState([]);
   const [lastPosition, setLastPosition] = useState(null);
+  const [undoHistory, setUndoHistory] = useState([]);
 
   useEffect(() => {
     const canvas = canvasRef.current;
+    if (!canvas) return;
+    
     const ctx = canvas.getContext('2d');
+    if (!ctx) return;
     
     // Set initial canvas size
     canvas.width = window.innerWidth - 300;
     canvas.height = window.innerHeight - 100;
 
-    // Draw history
+    // Clear canvas first
+    ctx.clearRect(0, 0, canvas.width, canvas.height);
+
+    // Draw all shapes
+    shapes.forEach((shape) => {
+      drawShape(ctx, shape);
+    });
+
+    // Draw all pencil strokes from history
     history.forEach((action) => {
       if (action.type === 'draw') {
         drawLine(ctx, action.x1, action.y1, action.x2, action.y2, action.color, action.thickness);
       }
     });
 
-    // Draw shapes
     shapes.forEach((shape) => {
       drawShape(ctx, shape);
     });
+
+    // Draw history (for pencil drawing)
+    history.forEach((action) => {
+      if (action.type === 'draw') {
+        drawLine(ctx, action.x1, action.y1, action.x2, action.y2, action.color, action.thickness);
+      }
+    });
   }, [history, shapes]);
 
-  const drawLine = (ctx, x1, y1, x2, y2, color, thickness) => {
-    ctx.beginPath();
-    ctx.moveTo(x1, y1);
-    ctx.lineTo(x2, y2);
-    ctx.strokeStyle = color;
-    ctx.lineWidth = thickness;
-    ctx.lineCap = 'round';
-    ctx.stroke();
-  };
-
-  const drawShape = (ctx, shape) => {
-    ctx.beginPath();
-    ctx.strokeStyle = shape.color;
-    ctx.lineWidth = shape.thickness;
-    ctx.lineCap = 'round';
-
-    if (shape.type === 'rectangle') {
-      ctx.rect(shape.x, shape.y, shape.width, shape.height);
-    } else if (shape.type === 'circle') {
-      ctx.arc(shape.x, shape.y, shape.radius, 0, Math.PI * 2);
-    }
-
-    ctx.stroke();
-  };
-
   const handleMouseDown = (e) => {
     setIsDrawing(true);
     const canvas = canvasRef.current;
@@ -108,7 +130,7 @@ const DrawingCanvas = ({ color, setColor, thickness, setThickness, history, setH
         ctx.stroke();
 
         // Update history
-        setHistory([...history, {
+        setHistory(prevHistory => [...prevHistory, {
           type: 'draw',
           x1: lastPos.x,
           y1: lastPos.y,
@@ -136,45 +158,56 @@ const DrawingCanvas = ({ color, setColor, thickness, setThickness, history, setH
         }
         return shape;
       });
+      
+      // Add shape to history when it's created
+      if (updatedShapes.length > 0) {
+        const lastShape = updatedShapes[updatedShapes.length - 1];
+        setHistory(prevHistory => [...prevHistory, {
+          type: 'shape',
+          shape: lastShape
+        }]);
+      }
+      
       setShapes(updatedShapes);
     }
   };
 
-  // Separate function to handle shape drawing
-  useEffect(() => {
-    const canvas = canvasRef.current;
-    const ctx = canvas.getContext('2d');
-    
-    // Clear canvas and redraw all shapes
-    ctx.clearRect(0, 0, canvas.width, canvas.height);
-    
-    // Draw all shapes
-    shapes.forEach((shape) => {
-      drawShape(ctx, shape);
-    });
-
-    // Draw history (for pencil drawing)
-    history.forEach((action) => {
-      if (action.type === 'draw') {
-        drawLine(ctx, action.x1, action.y1, action.x2, action.y2, action.color, action.thickness);
-      }
-    });
-  }, [shapes, history]);
-
   const handleMouseUp = () => {
     setIsDrawing(false);
-    // Clear last position when mouse is released
     setLastPosition(null);
+    setUndoHistory([]);
   };
 
   const handleUndo = () => {
     if (history.length > 0) {
-      setHistory(history.slice(0, -1));
+      // Clear the last action from history
+      setHistory(prevHistory => prevHistory.slice(0, -1));
+      
+      // Add it to undo history
+      setUndoHistory(prev => [...prev, history[history.length - 1]]);
+      
+      // Clear the last shape if it exists
+      if (shapes.length > 0) {
+        setShapes(prevShapes => prevShapes.slice(0, -1));
+      }
     }
   };
 
   const handleRedo = () => {
-    // Implement redo functionality
+    if (undoHistory.length > 0) {
+      const lastUndo = undoHistory[undoHistory.length - 1];
+      
+      // Add the action back to history
+      setHistory(prevHistory => [...prevHistory, lastUndo]);
+      
+      // Remove it from undo history
+      setUndoHistory(prev => prev.slice(0, -1));
+      
+      // Add the shape back if it exists
+      if (lastUndo.type === 'shape') {
+        setShapes(prevShapes => [...prevShapes, lastUndo.shape]);
+      }
+    }
   };
 
   return (
@@ -189,10 +222,10 @@ const DrawingCanvas = ({ color, setColor, thickness, setThickness, history, setH
         <button onClick={() => setCurrentTool('circle')} className={`tool-button ${currentTool === 'circle' ? 'active' : ''}`}>
           ⭕
         </button>
-        <button onClick={handleUndo} className="tool-button">
+        <button onClick={handleUndo} className="tool-button" disabled={history.length === 0}>
           ↺
         </button>
-        <button onClick={handleRedo} className="tool-button">
+        <button onClick={handleRedo} className="tool-button" disabled={undoHistory.length === 0}>
           ↻
         </button>
         <div className="color-picker">
@@ -211,9 +244,6 @@ const DrawingCanvas = ({ color, setColor, thickness, setThickness, history, setH
           onMouseDown={handleMouseDown}
           onMouseMove={handleMouseMove}
           onMouseUp={handleMouseUp}
-          max="20" 
-          value={thickness} 
-          onChange={(e) => setThickness(e.target.value)}
         />
       </div>
     </div>