              

              

            

             

               

            

               

                     

               

            

              

              

              C2C

  B2C                

              

                  

               

  

      2021              

            

             

             

           

            

              

           

              

               

  

                   

                

             

              

           

                

             

              



                     

             

              

              

            

               

               

                   

                 

             

             

            

            

                

            

            

            

                    

             

               

                  

   

                      

            

            

           

             

           