const colors1 = ['#111', '#222', '#333'];
const colors2 = ['#444', '#555', '#666'];

const colorChoice = (n) => {
  return n[Math.floor(Math.random() * n.length)];
};

colorChoice(colors1);
// Returns one of: ['#111', '#222', '#333']

colorChoice(colors2);
// Returns one of: ['#444', '#555', '#666']