My beautiful rainbow

Like an arc of colour striding across my flat, grey sky. You appear from nowhere and the joy you bring lifts my heart and sets it afire with a love so strong, so true. Just like a rainbow you're tantalisingly visible but always just out of reach; untouchable, beyond my hopeful grasp. And if I try and chase you to your secret end; I wonder will I find the golden treasure that I've dreamed of?