144 tiles, often green and white in color, always clicking and clacking throughout the strategic, four-person game. It’s been around since the 1800s, and it crossed the biggest ocean in the world to arrive here in America, where decades later, it’s become a phenomenon. Mahjong is taking over social clubs, senior centers, kitchen tables and even breweries around the country – and here in Boston. Two local experts give us the inside scoop on all things Chinese mahjong.