Resize gameObject when it has extended a restricted area

So here i have an image will provide a better understanding of my problem. So currently i have some white blocks and within the white blocks i have some cyan bordered boxes. So the current problem i want to solve now is. Whenever the white boxes are extended outside the cyan bordered boxes. I want to resize them so they are inside the cyan bordered boxes. Such like the one fifth on from the top.

How can i solve this problem ?

Thanks in advance.

Edit

 void Update() {

     if( numOfGeneratedGuideline < numOfGuidelineToGenerate ) {
         Generate_Guideline_Positons(numOfGeneratedGuideline);
         Generate_Platform_Positions_And_Scale(numOfGeneratedGuideline);
         Generate_Platforms(numOfGeneratedGuideline);
         numOfGeneratedGuideline++;
     }

 }

 void Generate_Guideline_Positons(int i) {

     float tempGuidelineOffset = groundHeight + ( guidelineOffset * ( i + 1 ) );

     guidelinePosX[i] = worldWidth / 2;
     guidelinePosY[i] = tempGuidelineOffset;
     guidelinePosZ[i] = 0;

 }

 void Generate_Platform_Positions_And_Scale(int i) {

     randomGuidelineNumber = Random.Range(1, numOfGuidelineToGenerate + 1);

     float tempPlatformPosXMin = ( worldWidth - guidelineWidth ) / 2;
     Debug.Log(tempPlatformPosXMin);
     float tempPlatformPosXMax = worldWidth - tempPlatformPosXMin;
     Debug.Log(tempPlatformPosXMax);
     float tempPlatformPosY = groundHeight + ( guidelineOffset * ( i + 1 ) );

     platformPosX[i] = Random.Range(tempPlatformPosXMin, tempPlatformPosXMax);
     platformPosY[i] = tempPlatformPosY;
     platformPosZ[i] = 0;
     
     platformScaleX[i] = Random.Range(minPlatformScaleRange, maxPlatformScaleRange);
     platformScaleY[i] = 1;
     platformScaleZ[i] = 1;

     //22 29 36 43 50

 }

 void Generate_Platforms(int i) {

     GameObject newplatform = Instantiate(platformPrefab, new Vector3(platformPosX[i], platformPosY[i], platformPosZ[i]), Quaternion.identity) as GameObject;
     newplatform.transform.localScale = new Vector3(platformScaleX[i], platformScaleY[i], platformScaleZ[i]);

 }