.sub-collections-section {
  width: 100%;
}

.sub-collections-section.fullwidth {
  max-width: none;
  margin-left: -20px;
  margin-right: -20px;
  width: calc(100% + 40px);
}

@media screen and (min-width: 750px) {
  .sub-collections-section.fullwidth {
    margin-left: -100px;
    margin-right: -100px;
    width: calc(100% + 200px);
  }
}