/* There is now a `gap` CSS property

** This works for <flex>, <grid>, and <multicolumn> layouts

** #box{} would lay out all it's children with 10px spacing between 

** different rows and 20px betwen different columns

*/

#box {

  display: flex;

  flex-wrap: wrap;

  gap: 10px 20px; /* row-gap [column-gap]*/

}

​

/* Supported by most modern browesers, Safari excluded. */