Unless you consider the "Y"s on the back of the card lowercase, the three "i"s are the only lowercase letter, which draws attention to them. That gives you three dots or "three point". Z also misspelled "paradise", subsiituting "C" for "S". C is the only misspelling, drawing attention, and is the third letter of the alphabet.Attention is also drawn to the letter "N", which is the only backward letter, and is the 14th letter of the alphabet. Combining those elements gives you 3.14.
The hand on the front of the card shows three fingers which could represent the number three. The thumb and forefinger create a circle, which could signify a "point". And then the number "14" is added to the hand by Z. (even without the circled thumb and forefinger the three fingers could be seen as points)3.14.
Gaik's birthday is march 14th.