With code and sample data below, I plot a gt table:
df <- structure(list(date = c("2016-1-31", "2016-2-29", "2016-3-31", 
"2016-4-30", "2016-5-31", "2016-6-30", "2016-7-31", "2016-8-31", 
"2016-9-30"), value1 = c(-15.25, -27.96, 7.53, -5.24, -6.93, 
-6.83, -6.47, 13, -10.48), value2 = c(-19.93, -13.76, 20, -11.12, 
-0.59, -9.06, 15, 1.66, -1.59)), class = "data.frame", row.names = c(NA, 
-9L))
library(gt)
library(tidyverse)
df %>% 
  gt() %>% 
  data_color(
    columns = value1:value2,
    colors = scales::col_numeric(
      palette = c(
        'red', 'yellow', 'green'),
      domain = c(df$value1, df$value2))
  )

Next step I attempted to achieve an approximately same color effect as the following plot, which I have done by the simply selecting the default 3-color scale: red, yellow, green from the Format Style drop-down list in Excel.

Does someone knows the values of the following hex color codes or other R's color palette could achieve same effect? Thanks.

Update: I obtain the similar color codes: "#f8696b", "#ffeb84", "#63be7b"
df %>% 
  gt() %>% 
  data_color(
    columns = value1:value2,
    colors = scales::col_numeric(
      palette = c(
        "#f8696b", "#ffeb84", "#63be7b"),
      domain = c(df$value1, df$value2))
  )
