A helpful tip,
If you ever encounter the white screen again.
Please change the name of the theme from wp-content/themes/circleflip
to any other name (make sure you have a default theme installed, like TwentyFifteen)
That should deactivate the theme circleflip
This also works with plugins.
So if you need to, you can change the name of wp-content/plugins/circleflip-portfolio-plugin