Hi can anyone offer some help/advice please. Went out in the d2 today but had very spongy brakes. Got worse so got her home. No brake fluid in the pot ?. However under the abs pump is looking like brake fluid has been leaking. Could someone give me a starting point to look for please. Photos below of the fluid under pump. Thank you all in advance

Fill the reservoir with fresh fluid.
Then get helper to press the brake pedal, while you look to see where its leaking from.

Clean the area as best you can too, soak a cloth in brake cleaner and it'll wipe away the old fluid