Length/Percentage of a line within a polygon square.

Grid lines and blue lines have been plotted as lines. Numbers are labels.

I'd like to calculate the length of each line inside each polygon.

So the line starting at (1,1) goes through the square 1 and square 2 and beyond.

What percentage of the line is inside square 1 and what percentage is in line 2?

Or what is the length of the line inside each square?

Thanks for your time.