Here's some technical details about the colors:
Body background-color: #FFFFFF, rgb: 255, 255, 255
Code/Blockquote background-color: #F5FDFF, rgb: 245, 253, 255
It's nearly white! Color-wise, I would classify it under gray not blue. I suggest increasing the saturation (hsv) by at least 8 units to #E0F9FF, rgb: 224, 249, 255.
For comparison, the color here ...
I'll try and address your issues individually here:
As I stated, this new box requires a click to invoke and a click to dismiss, making it more work than the previous one.
This is intentional, the hover behavior was not intuitive. We do however enable hovering once you click to open any of the buttons on the left, since you have declared your intent.