What are the Quranic verses and Prophetic hadiths that indicate that Qiyam al-Layl (night prayer) begins after the 'Isha prayer and ends before Fajr (dawn), and why does it not begin after Maghrib (sunset)?

The time for Qiyam al-Layl (night vigil prayer) begins after the 'Isha prayer and extends until the Fajr (dawn) prayer. The actions and sayings of the Prophet, peace and blessings be upon him, confirm this, as does the view of the majority of scholars. The Hanbalis, however, held that its time begins from Maghrib (sunset prayer). Performing voluntary prayers between Maghrib and 'Isha has merit, and some of the Salaf (early Muslims) considered it a part of Qiyam al-Layl.