(CNN)By the elation online and in the streets, you'd think Iran had just won the World Cup. But this is bigger. Iranians erupted in celebration as young people waved flags from their sunroofs, blasted music from stereos and chatted online with the hashtag #IranTalks. The excitement came after a breakthrough nuclear deal with the United States and other world powers that promises to end Iran's international isolation under years of crippling sanctions. Just before midnight on Thursday, Vali Asr street, one of Tehran's main thoroughfares, turned into something like a block party. Car horns blared. Men danced in the middle of traffic. Some people flaunted U.S. dollar bills. It was a fitting double occasion: The agreement was struck on the final day of Persian New Year festivities, symbolizing a fresh start. Milad, a 20-year-old university student among the crowds, told CNN he was happy about the accord but wary about his own future. "I still believe I'll have a hard time finding a job that pays well, with or without this deal." Another Tehran resident, Alireza, 37, said "Things can't get worse than they are so, I'm happy with this news." "This is pretty historic and I pray that my children will be able to live in an Iran that can play nice with the international community." At home that evening, families watched as Iranian state television broadcast U.S. President Barack Obama's speech live, which came for many as a surprise. Some Iranians celebrated the moment by snapping selfies in front of the TV. Iranian foreign minister Javad Zarif — who led the Iranian negotiation team — received a hero's welcome as he arrived in Iran on a sunny Friday morning. "Long live Zarif," crowds chanted as the vehicle rolled slowly down the packed street, carrying the man who struck the historic deal. Other videos posted to social media showed Zarif mobbed by fans in Switzerland, who yelled "We love you, Zarif!" Lausanne: Zarif joins Iranian students cheer "Zarif We Love You" outside press conference at #IranTalks. pic.twitter.com/S2dVzeAsZl . Negar Mortazavi, an Iranian-American independent journalist, celebrated with her friends in the United States by singing "Bayram Mubarak," a New Year song. Happy New Day, New Year, New Era. #IranTalks pic.twitter.com/OuGE3pu8Z1 . She closely followed the reaction from Iranians around the world and told CNN she saw an "explosion" of joy when the deal was finally struck. "I didn't expect so many people to follow it so closely, but from the result, I can tell everyone was following." "After 35 years of animosity, U.S. and Iran diplomats shook hands and stood by each other in public... everything is just pushing this forward."
Iranians celebrate deal online and in the streets .