* {
  box-sizing: border-box;
}

.desktop {}
.desktab {}
.tablet {}
.mobile {}
.respcol {
   float:left;
   width:50%;
}

  @media screen and (min-width: 920px) { 
    /* desktop  */
    body {}
    .bigtable {width:1048px}
    .desktop {}
    .desktab {}
    .tablet {display:none;}
    .mobile {display:none;}
    .regtable {width:320}
  }
/*  @media screen and (min-width: 728px) and (max-width: 920px) { */
  @media screen and (max-width: 920px) {
    /* tablet  (888+list)  */
    body {}
    .bigtable {width:728px}
    .desktop {display:none;}
    .desktab {}
    .tablet {}
    .mobile {display:none;}
    .respcol {width:100%}
    .regtable {width:480}
  }
/*  @media screen and (max-width: 728px) { 
    ( mobile )
    body {background-color:white;}  
    .bigtable {width:728px}
    .desktop {display:none;}
    .desktab {display:none;}
    .tablet {display:none;}
    .mobile {}
    .respcol {width:100%}
    .regtable {width:320}
  }
*/
/*  @media screen and (max-width: 728px) {
    body {background-color:lightgreen;}  
    .bigtable {width:360px}
    .desktop {display:none;}
    .desktab {display:none;}
    .tablet {display:none;}
    .mobile {}
    .mux-table {width:100%}
    .mux-table td:nth-child(4),td:nth-child(6),td:nth-child(8),td:nth-child(9),td:nth-child(10),td:nth-child(11) {display:none;}
  }  */