Source: https://www.elegantthemes.com/blog/divi-resources/how-to-change-the-number-of-columns-in-the-divi-blog-module

Creates x columns of 200px width

• Set the blog/portfolio module design to fullwidth
• Give the module a custom class hws-posttype-css-grid
• Gap: 20px; = same gap between items all sided
• Gap: 20px 50px; = different gap between rows and columns

/** START post type with css grid **/
/* create css grid column template */
.hws-posttype-css-grid > div {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(275px, 1fr));
  gap: 16px;
}
/* remove pagination from blog grid with absolute position */
.hws-posttype-css-grid.et_pb_posts  > div > div,
.hws-posttype-css-grid .pagination {
  width: 100%;
  position: absolute;
  bottom: 0;
  transform: translate(0%, 150%);
}
/** END post type module with css grid **/Code language: CSS (css)