Gmail question: I like the old interface because the contrast between the buttons and background are easier to see faster. So I click "Older Version" in the top

Gmail question: I like the old interface because the contrast between the buttons and background are easier to see faster. So I click "Older Version" in the top right corner of the screen to switch to the older version. The next time I close the window with Gmail in it, and go back to Gmail, I'm back using the new version. All thoughts/solutions very welcome and appreciated.