docs: controls & things i want

README.md

@@ -1,3 +1,17 @@
 # [grid](https://leodog896.github.io/grid)
 
 Infinite clickable grid as a website.
+
+## Controls
+
+- Drag left click to move around
+- Click a cell to toggle it
+- Alt+click to cycle color
+  - Alt+shift+click to cycle color the other direction
+
+## Things I want
+
+- [x] Colors
+- [] Select multiple items
+- [] 3d grid (not display; just time travel; go between z layers at +-1)
+- [] Palette changing