What Was The Earth Like During The Jurassic Period_

Approximately 65 million years ago, the Earth was inhabited by reptiles of all sizes and colors; these managed to thrive for millions of years to dominate every corner of the planet, from the Earth to the sky and the oceans. But one fateful day, a massive rock from space ended this paradise, causing a cataclysm that eliminate 70% of living beings, ending the reign of those who, until then, ruled the world.
But what was the planet like during the time of the dinosaurs before the meteorite fell? Did the same plants exist as today? Were there winters?