In one aspect, a covering for an architectural structure includes a headrail, a bottom rail supported relative to the headrail, and at least one stackable covering element positioned between the headrail and the bottom rail. The covering also includes an overpowered lift system configured to provide a lifting force that raises the bottom rail relative to the headrail towards a retracted position of the covering. In addition, the covering includes retention structure provided in operative association with the bottom rail, with the retention structure being configured to engage at least one hold-down bracket to hold the bottom rail in position relative to the headrail against the lifting force provided by the overpowered lift system.