Popsu-coloque/web/core/profiles/demo_umami/themes/umami/layouts/threecol_section/threecol_section.css

/*
 * @file
 * Provides the layout styles for three-column layout section.
 */

.layout--threecol-section {
  display: flex;
  flex-wrap: wrap;
}

.layout--threecol-section > .layout__region {
  flex: 0 1 100%;
}
/* Medium */
@media screen and (min-width: 48em) { /* 768px */
  .layout--threecol-section {
    margin-right: -1.5%;
    margin-left: -1.5%;
  }
  .layout--threecol-section > .layout__region {
    margin-right: 1.5%;
    margin-left: 1.5%;
  }
  .layout--threecol-section--25-50-25 > .layout__region--first,
  .layout--threecol-section--25-50-25 > .layout__region--third,
  .layout--threecol-section--25-25-50 > .layout__region--first,
  .layout--threecol-section--25-25-50 > .layout__region--second,
  .layout--threecol-section--50-25-25 > .layout__region--second,
  .layout--threecol-section--50-25-25 > .layout__region--third {
    flex: 0 1 22%;
  }
  .layout--threecol-section--25-50-25 > .layout__region--second,
  .layout--threecol-section--25-25-50 > .layout__region--third,
  .layout--threecol-section--50-25-25 > .layout__region--first {
    flex: 0 1 47%;
  }
  .layout--threecol-section--33-34-33 > .layout__region--first,
  .layout--threecol-section--33-34-33 > .layout__region--third {
    flex: 0 1 30%;
  }
  .layout--threecol-section--33-34-33 > .layout__region--second {
    flex: 0 1 31%;
  }
}