diff --git a/tui.c b/tui.c
index aa86d4c..6ffbaf1 100644
--- a/tui.c
+++ b/tui.c
@@ -1002,16 +1002,16 @@ void tui_run(Engine *engine) {
         if (zoom_mode) {
             switch (ch) {
                 case 'h': case KEY_LEFT:
-                    selected_col = (selected_col - 1 + GRID_COLS) % GRID_COLS;
+                    selected_grid = (selected_grid - 1 + NUM_GRIDS) % NUM_GRIDS;
                     break;
                 case 'l': case KEY_RIGHT:
-                    selected_col = (selected_col + 1) % GRID_COLS;
+                    selected_grid = (selected_grid + 1) % NUM_GRIDS;
                     break;
                 case 'j': case KEY_DOWN:
-                    selected_row = (selected_row + 1) % GRID_ROWS;
+                    selected_grid = (selected_grid + 4) % NUM_GRIDS;  // Move down a row (4 grids per row)
                     break;
                 case 'k': case KEY_UP:
-                    selected_row = (selected_row - 1 + GRID_ROWS) % GRID_ROWS;
+                    selected_grid = (selected_grid - 4 + NUM_GRIDS) % NUM_GRIDS;  // Move up a row
                     break;
                 case '\n': case '\r':
                     // Select this grid and exit zoom mode