I've noticed this with all Snap to Grid or Snap to Objects in office. It's that I can seemingly snap anything to the grid, but office takes the thickness of the line (on my rectangle etc.) into account when snapping, and if I don't do it just right, I could end up actually snapping the center of the line, one side of the line, or another when snapping.
Let me show you what I'm working on. I'm creating bookmarks for my Bible to keep track where I am in certain places. The number headings are 0.6"x0.6" and the names of the sections (sorry they're upside down) are 2.2"x0.6" and the 1-0 numbers are 4"x0.6". I adjusted the gridlines and origin to snap each object to the grid. But as you can see, they're still off! And I've noticed that in snapping things to the grid, I can put it generally at the grid, but Word or PowerPoint will let the object shift around in case I want it inside or outside or right on the grid. In my mind, a line in geometry is infinitesimally thin, so even though a line has thickness in my project, the line should straddle the grid only. Is there a setting that I can use to make it do that?
Image upload is broken😵💫
Here are my screenshots. You can see they're not aligned even though I've snapped them to the grid several times.
