I've been struggling with this for the last couple of days, I'm trying to get an editable grid view system in asp.net using the fallowing tutorial:

Editable Grid View System using BootStrap in ASP.Net

I want to be able click "add new record" and the pop up modal should display and let me add a new record, the issue that I'm having is that whenever I clicked on "add new record" the

seems to be covering everything.

Here are some pictures describing the problem.

Before I clicked:

And after I clicked:

I can't seem to find what's causing this.

Please take a look at my code:

   
   
     
     
     
      
   
   
     

     


             
             
Grid View System

        

            

                

                    

                        

                            

                        

                        

                            

                        

                        

                            

                        

                        

                        

                        

                        

                        

                    

                

                

            

            

            

        

        


            


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Details

            

            


                

                    

                        

                            

                                

                                

                                

                                

                            

                        

                    

                    

                        

                        

                    

                

                


                    Close

                

            

        

        


            


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Edit Record

            

            

                

                    


                        

                        


                            


                                
Name : 

                                


                                    

                                


                            

                            


                                
EmailID

                                


                                    

                            

                            


                                
Address

                                


                                    

                            

                            


                                
Contact No

                                


                                    

                            

                        

                    

                    


                        

                        

                        Close

                    

                

                

                    

                    

                

            

        

        


            


                 


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Add New Record

            

            

                

                    


                        


                            


                                
Name : 

                                


                                    

                            

                            


                                
EmailID :

                                


                                    

                            

                            


                                
Address:

                                


                                    

                            

                            


                                
Contact No:

                                


                                    

                            

                        

                    

                    


                        

                        Close

                    

                

                

                    

                

            

            

        

        


            


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Delete Record

            

            

                

                    


                        Are you sure you want to delete the record?

                        

                    

                    


                        

                        Cancel

                    

                

                

                    

                

            

        

C# code behind:

   protected void btnAdd_Click(object sender, EventArgs e)
   {
        System.Text.StringBuilder sb = new System.Text.StringBuilder();

        sb.Append(@"");

        ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "AddShowModalScript", sb.ToString(), false);
   }

I'd really appreciate any suggestions. Thank you.