What is the rule regarding stopping on a pedestrian crosswalk (senda peatonal) while waiting for a traffic light to turn green?

1. Drivers may stop on the pedestrian crossing if their front wheels are over the line
2. Drivers must stop before the stop line without encroaching upon or blocking the pedestrian crossing at any time
3. Stopping on the zebra crossing is permitted if hazard lights are active
4. Pedestrian crossings are only protected during school hours