* {box-sizing: border-box;}
.wrapper {
  max-width: 95%;
  padding: 2vmin;
}

.wrapper > div {
  border: 0px solid silver;
  border-radius: 3px;
  background-color: #ffffff;
  padding: 2px;
  color: #0;
  font-family: "Microsoft JhengHei";
  font-size: 2.5vmin;
}
.wrapper {
  display: grid;
  grid-template-columns: 1fr 2fr;
  grid-gap: 10px;
  grid-auto-rows: minmax(10vmin,auto);
}
.prod_menu {
  grid-column: 1/3 ;
  grid-row: 1; 
}

.prod_image { 
  grid-column: 1;
  grid-row: 2/6;
}

.prod_spec {
  grid-column: 2;
  grid-row: 2;
}
.prod_desc {
  grid-column: 2;
  grid-row: 3/5;
}
.prod_method {
  grid-column: 2;
  grid-row: 5;
}

.prod_field{ 
  background-color: #fdf3cf;
  color: #307c70;
  font-size: 3vmin;
  line-height: 6vmin;
 }
 
 .prod_field2{ 
  font-size: 1.5vmin;
 }
 
.prod_content{ 
  background-color: #ffffff;
  color: #307c70;
  padding: 3vmin;
  
}

@media only screen and (max-width:620px) {
  /* For mobile phones: */
  .prod_image, .prod_spec, .prod_desc, .prod_method {
    width:100%;
  }
}