kableExtra column_spec宽度不起作用

library(kableExtra)
library(dplyr)

data <- data.frame(
  Name = c("John Doe", "Jane Smith", "Long Name Example"),
  Age = c(30, 25, 40),
  stringsAsFactors = FALSE
)

data %>%
  kable() %>%
  kable_styling(full_width = FALSE) %>%
  column_spec(1, width = "10em") %>%
  column_spec(2, width = "5em")

data %>%
  kable() %>%
  kable_styling(full_width = TRUE) %>%
  column_spec(1, width = "10em") %>%
  column_spec(2, width = "5em")

data %>%
  kable() %>%
  kable_styling(bootstrap_options = c("striped", "hover"), full_width = FALSE) %>%
  column_spec(1, width = "10em") %>%
  column_spec(2, width = "5em") %>%
  add_header_above(c("Personal Info" = 2))

<style>
  table {
    width: 100%;
  }
  .kable-table td:nth-child(1), .kable-table th:nth-child(1) {
    width: 10em;
  }
  .kable-table td:nth-child(2), .kable-table th:nth-child(2) {
    width: 5em;
  }
</style>