More style questions using formattable - r

Question

In the table below, how do I remove the line between the Canada row and the World row?
Also, how do I remove the bold from the column headers (ie 1980, 2019, Change)?
This is different than the proposed link in that I wonder if there is a solution that is of the form:
# Define styles
row_emphasis <- formatter("span", style = ~style("font.weight" = "bold", "font.size" = "18px"))
make_non_bold <- formatter("span", style = "font-style:italic; font-weight:normal")
# Apply styles
formattable(can_world_table, list(
area(row = 1) ~ row_emphasis,
# column headers # ~ make_non_bold
))
As for the part about removing the lines between rows, the suggested answer below does not address my issue. This code adds another line between Canada and the header row line:
row_emphasis <- formatter("span", style = ~style("font.weight" = "bold", "font.size" = "18px", "border-top: 1px solid green"))
library(tidyverse)
library(formattable)
target_year = 1980
current_year = 2019
can_target = 20.464
can2019 = 37.786
world_target = 6123
world2019 = 7456
can_change <- (can2019 - can_target) / can_target
world_change <- (world2019 - world_target) / world_target
can_world_table <- tibble(
region = c("Canada", "World"),
ty = c(round(can_target, digits = 0), round(world_target, digits = -2)),
cy = c(can2019, round(world2019, digits = -2)),
change = percent(c(can_change, world_change), 0)
) %>%
set_names(c("", target_year, current_year, "Change"))
can_world_table
can_world_table <- tibble(
region = c("Canada", "World"),
ty = c(can_target, format(round(world_target, digits = -2), big.mark = ",")),
cy = c(can2019, format(round(world2019, digits = -2), big.mark = ",")),
change = percent(c(can_change, world_change), 0)
) %>%
set_names(c(" ", target_year, current_year, "Change"))
row_emphasis <- formatter("span", style = ~style("font.weight" = "bold", "font.size" = "18px"))
formattable(can_world_table, list(
area(row = 1) ~ row_emphasis
))