URL：https://media.istockphoto.com/vectors/realistic-seventeen-years-anniversary-celebration-design-golden-and-vector-id1127572392?k=6&m=1127572392&s=612x612&w=0&h=TBzEkPqfY-oJ6QwLigmAYjHLean9x7ZIjKyDvbsFyoc=
掲載元：https://www.istockphoto.com/jp/イラスト/数字の17
