The ported page rendered edge-to-edge: the GPS bar started right at
the top of the screen and the footer sat against the navigation bar,
so system UI overlapped the content (user: "顶头"). The reference app
is not edge-to-edge and keeps its content inside the safe area.
Add windowInsetsPadding(WindowInsets.systemBars) on the page root
column, shrinking the top and bottom by the status/navigation bar
height exactly as the user requested ("上方和下方往里面缩一点点").
Grid columns (60/200/60dp), rows, marker lookup and all logic are
untouched - verified pixel-identical column ratios vs the reference
screenshot (147:395:147 vs 146:395:148).
Verified: feature + app compile, 11 unit tests pass.
mckero
675194075e