ol li{margin-bottom:0.5em;}

@media screen and (min-width:640px){
 /* for PC*/
 table.tbbook{
  margin-left: auto;
  margin-right: auto;
  width:400px;
 }

 img.hotjpg{
  width:410px;
  height:300px;
  display: block;
  margin-left: auto;
  margin-right: auto;
 }

}

@media screen and (max-width:640px){
/* for smart phone or Tablet device*/

 table.tbbook{
  margin-left: auto;
  margin-right: auto;
  width:100vw;
  max-width:400px;
 }

 img.hotjpg{
  width:70vw;
  height:auto:
  max-width:410px;
  display: block;
  margin-left: auto;
  margin-right: auto;
 }

}