.ona-mock-page .ona-mock-main {
  width: calc(100% - var(--sidebarW));
  max-width: 980px;
  margin-right: auto;
  margin-left: var(--sidebarW);
  box-sizing: border-box;
}

@media (max-width: 768px) {
  .ona-mock-page .ona-mock-main {
    width: 100%;
    margin-right: auto;
    margin-left: 0;
  }
}