pathways: bigger tiles, less chrome, no covered photos

- tiles 240px desktop / 150px mobile
- remove hint bar; trim splash to a single line; drop counts from
  hover labels and the move flash
- collision-safe placement: when a step lands on a cell already held
  by a different photo, keep stepping in that direction to the first
  free cell instead of overwriting, so returning photos are never
  covered or orphaned

1 files changed, 3 insertions, 1 deletions

diff --git a/README.md b/README.md
index 36e7b53..8a0496b 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,9 @@ stays behind basic auth at <https://prism.dax.ist>; pathways is public.
   grey → grey → … and wraps around. Assignment is deterministic, so revisiting
   a photo always offers the same four exits.
 - If a step lands on a photo already placed in the mosaic, focus just jumps to
-  its existing tile — the mosaic never holds two copies.
+  its existing tile — the mosaic never holds two copies. If it lands on a grid
+  cell already occupied by a *different* photo, the new photo keeps stepping in
+  that direction until it finds a free cell, so nothing is ever covered up.
 
 ## Run it