The cells_stub() function

Use sza to create a gt table. Color all of the month values in the table stub with tab_style(), using cells_stub() in locations.

sza |>
  dplyr::filter(latitude == 20 & tst <= "1000") |>
  dplyr::select(-latitude) |>
  dplyr::filter(!is.na(sza)) |>
  tidyr::spread(key = "tst", value = sza) |>
  gt(rowname_col = "month") |>
  sub_missing(missing_text = "") |>
  tab_style(
    style = list(
      cell_fill(color = "darkblue"),
      cell_text(color = "white")
      ),
    locations = cells_stub()
  )
0530 0600 0630 0700 0730 0800 0830 0900 0930 1000
jan 84.9 78.7 72.7 66.1 61.5 56.5 52.1
feb 88.9 82.5 75.8 69.6 63.3 57.7 52.2 47.4
mar 85.7 78.8 72.0 65.2 58.6 52.3 46.2 40.5
apr 88.5 81.5 74.4 67.4 60.3 53.4 46.5 39.7 33.2
may 85.0 78.2 71.2 64.3 57.2 50.2 43.2 36.1 29.1
jun 89.2 82.7 76.0 69.3 62.5 55.7 48.8 41.9 35.0 28.1
jul 88.8 82.3 75.7 69.1 62.3 55.5 48.7 41.8 35.0 28.1
aug 83.8 77.1 70.2 63.3 56.4 49.4 42.4 35.4 28.3
sep 87.2 80.2 73.2 66.1 59.1 52.1 45.1 38.1 31.3
oct 84.1 77.1 70.2 63.3 56.5 49.9 43.5 37.5
nov 87.8 81.3 74.5 68.3 61.8 56.0 50.2 45.3
dec 84.3 78.0 71.8 66.1 60.5 55.6 50.9