.ten-columns .et_pb_module {width: 10%; float: left;}
.nine-columns .et_pb_module {width: 11.11%; float: left;}
.eight-columns .et_pb_module {width: 12.5%; float: left;}
.seven-columns .et_pb_module {width: 14.28%; float: left;}
.six-columns .et_pb_module {width: 16.66%; float: left;}
.five-columns .et_pb_module {width: 20%; float: left;}
/** set different col width based on position **/
.six-columns:nth-child(2) .et_pb_module {width: 33.32%; float: left;}
/*
OR TRY: .six-columns .et_pb_module:nth-of-type(2) {width: 33.32%; float: left;}
Remember to adjust column number so it sum up to 100%
... write more custom col width rules for your need
*/
@media (max-width:980px){
.ten-columns .et_pb_module {width: 20%;}
.nine-columns .et_pb_module {width: 33.3%;}
.eight-columns.et_pb_module {width: 25%;}
.seven-columns.et_pb_module {width: 25%;}
.six-columns .et_pb_module {width: 33.3%;}
.five-columns .et_pb_module {width: 33.3%;}
}
@media all and (max-width: 767px) {
.ten-columns .et_pb_module {width: 100%;}
.nine-columns .et_pb_module {width: 100%;}
.eight-columns .et_pb_module {width: 100%;}
.seven-columns .et_pb_module {width: 100%;}
.six-columns .et_pb_module {width: 100%;}
.five-columns .et_pb_module {width: 100%;}
}
.ten-columns .et_pb_module {width: 10%; float: left;}
.nine-columns .et_pb_module {width: 11.11%; float: left;}
.eight-columns .et_pb_module {width: 12.5%; float: left;}
.seven-columns .et_pb_module {width: 14.28%; float: left;}
.six-columns .et_pb_module {width: 16.66%; float: left;}
.five-columns .et_pb_module {width: 20%; float: left;}
@media (max-width:980px){
.ten-columns .et_pb_module {width: 20%;}
.nine-columns .et_pb_module {width: 33.3%;}
.eight-columns.et_pb_module {width: 25%;}
.seven-columns.et_pb_module {width: 25%;}
.six-columns .et_pb_module {width: 33.3%;}
.five-columns .et_pb_module {width: 33.3%;}
}
@media all and (max-width: 767px) {
.ten-columns .et_pb_module {width: 100%;}
.nine-columns .et_pb_module {width: 100%;}
.eight-columns .et_pb_module {width: 100%;}
.seven-columns .et_pb_module {width: 100%;}
.six-columns .et_pb_module {width: 100%;}
.five-columns .et_pb_module {width: 100%;}
}Paste the fallowing code
To use it simple use one of the predefined class like six-columns. Copy class name to a row -> advance -> custom css class field.
https://www.elegantthemes.com/blog/divi-resources/add-more-columns-to-your-divi-builder-posts-or-pages
https://stackoverflow.com/questions/2751127/how-to-select-the-first-second-or-third-element-with-a-given-class-name