Plotrix包3D饼图图例显示不全问题求助

我用plotrix包绘制3D饼图时，图例无法完整显示，图例框部分超出画布范围，之前求助过但未达到预期效果。当前生成的图表如下：

我的代码 #

pie1_PGS <- pie1_PGS[!(pie1_PGS$nb_sejours_2021 == 0),]

lab <- paste0(round(pie1_PGS$nb_sejours_2021/sum(pie1_PGS$nb_sejours_2021) * 100, 2), 
          "%")

library(plotrix)
pie3D(pie1_PGS$nb_sejours_2021, 
  radius = 0.75,
  height = 0.1,
  theta = 0.7,
  border = "white",
  col = rainbow(length(lab)),
  shade = 0.5,
  labels = lab,
  labelcol = "red",
  labelcex = 0.75,
  explode = 0.2,
  main = "Répartition des séjours 2021 par type") 
legend(0.5, 1.1, pie1_PGS$type_de_sejour, cex = 0.3, fill = rainbow(length(lab)))

我的数据集 #

structure(list(type_de_sejour = structure(c(1L, 2L, 4L), levels = c("Ambulatoires", 
"Externes", "Fictifs", "Hospitalisé"), class = "factor"), nb_sejours_2021 = c(20794, 
365, 7866)), row.names = c(1L, 2L, 4L), class = "data.frame")

恳请各位帮忙解决该问题！

内容的提问来源于stack exchange，提问作者gerardlambert