I want to specify the ylimits of each facet_wrap. Here is a reproducible example:

library(ggplot2)

# Example data
set.seed(123)
df <- data.frame(
  x = rep(1:10, 4),
  y = c(rnorm(10), rnorm(10, mean = 5), rnorm(10, mean = 10), rnorm(10, mean = 15)),
  facet = rep(letters[1:4], each = 10)
)

# Manually specified limits for each facet
facet_limits <- list(
  a = c(-2, 2),  # Facet a
  b = c(2, 8),   # Facet b
  c = c(8, 12),  # Facet c
  d = c(12, 18)  # Facet d
)

# Plot with manually set facet limits
ggplot(df, aes(x = x, y = y)) +
  geom_line() +
  facet_grid(. ~ facet, scales = "free_y") +
  lapply(seq_along(facet_limits), function(i) coord_cartesian(ylim = facet_limits[[i]]))

How can I achieve this? Thank you!