top layer is beauty, bottom is zion. original beauty block zion, so total show only beauty	上為女孩，下層國家公園。二圖層現只出現女孩因為zion被蓋住了
add mask on top layer, full opacity (white) then bottom canNOT come up. mask using full transparent (black) then zion come up completely	加 mask 在女孩，則有可能讓 zion 全顯現
top + mask (opacity instead transparent, since trans then zion show UP totally) then use brush can see mask effect	使用筆刷把國家公園給顯示出來的方法
you can also using gradient tool	你也可以使用漸層工具