Each line is a running total. It starts at zero on the 1st and climbs as money moves, so a steep stretch is a heavy day and a flat stretch is a quiet one.
Net so far, top left, is income minus spending to date. It turns red when it's negative.
Hover over the chart, tap it on a phone, or focus it and use the arrow keys to see that day's totals. Spent so far and Net so far follow along.
The spending line stays under the green line, ends below the budget line, and the pace label lands under your budget.