Short answers, pulled from the story.
The first true dome in India was completed around 1300. This architectural innovation arrived as a technological revolution carried by Central Asian conquerors rather than developing from the earth like the pyramids of Egypt or the temples of the subcontinent.
Muhammad of Ghor established Delhi as his capital in 1193. He brought with him a workforce trained in the stone masonry of the West to begin the transition from the corbelled arch to the true arch.
The Qutb Minar is a victory tower rising 73 meters to the sky. It stands as the most prominent symbol of the early Delhi Sultanate era and features four stages decorated with inscriptions and geometric patterns.
The Tughlaq dynasty ruled from 1320 to 1413. This period introduced a radical departure from decorative excesses by embracing a fortress-like austerity that mirrored the political instability of the age.
The Sixty Dome Mosque, completed in 1459 in the Mosque City of Bagerhat, is a UNESCO World Heritage Site. It showcases the multiplicity of doors and mihrabs, with 26 doors designed to increase light and ventilation.
The Taj Mahal was built as a mausoleum for Mumtaz Mahal, who died in 1631. It is the best known example of Mughal architecture and represents the culmination of all previous garden tomb ideas into a national landmark.