ggarrange - change background of shared legend and remove borders between plots - r

Question

I would like the background to all be navy blue without the white borders around the plots and the legend background to also be navy blue (no large white box). I have seen some solutions here but they seem needlessly complicated and would involve a lot of rewriting of the script or even switching packages. Surely there is an easier way? Thanks in advance.
Example script:
df <- data.frame(supp=rep(c("VC", "OJ"), each=3),
dose=rep(c("D0.5", "D1", "D2"),2),
len=c(6.8, 15, 33, 4.2, 10, 29.5))
cols <- c("VC" = "#0FC9F7", "OJ" = "#1010EB")
p1 <- ggplot(df, aes(x=dose, y=len, color=factor(supp))) +
geom_line(aes(group = supp)) +
theme(
plot.title = element_text(hjust = 0.5),
panel.background = element_rect(fill = "#140F4B",
colour = "#140F4B",
size = 0.5, linetype = "solid"),
panel.grid.major = element_blank(),
panel.grid.minor = element_blank(),
plot.background = element_rect(fill = "#140F4B"),
text = element_text(colour = "white"),
axis.line = element_line(colour = "white"),
axis.text = element_text(colour = "white")
) +
scale_color_manual(values = cols,
name = "supp",
breaks=c("VC", "OJ"),
labels=c("VC", "OJ"))
p2 <- ggplot(df, aes(x=dose, y=len, color=factor(supp))) +
geom_line(aes(group = supp)) +
theme(
plot.title = element_text(hjust = 0.5),
panel.background = element_rect(fill = "#140F4B",
colour = "#140F4B",
size = 0.5, linetype = "solid"),
panel.grid.major = element_blank(),
panel.grid.minor = element_blank(),
plot.background = element_rect(fill = "#140F4B"),
text = element_text(colour = "white"),
axis.line = element_line(colour = "white"),
axis.text = element_text(colour = "white")
) +
scale_color_manual(values = cols,
name = "supp",
breaks=c("VC", "OJ"),
labels=c("VC", "OJ"))
plots <- list(p1, p2)
combined_plots <- ggpubr::ggarrange(plotlist = plots,
ncol = 2, nrow = 1, align = "hv", common.legend = TRUE, legend = "bottom")
#Annotate plot
combined_plots <- annotate_figure(
combined_plots,
top = text_grob(paste0("Example"), size = 18, color = "white")
) + bgcolor("#140F4B")+ border("#140F4B")

Answer 1

It looks like the problem is that there is a missing legend.background in your theme which might explain why there is a white background around your legend. I managed to solve the problem using patchwork! Hopefully, this helps.
library(ggplot2)
library(patchwork)
df <- data.frame(supp=rep(c("VC", "OJ"), each=3),
dose=rep(c("D0.5", "D1", "D2"),2),
len=c(6.8, 15, 33, 4.2, 10, 29.5))
cols <- c("VC" = "#0FC9F7", "OJ" = "#1010EB")
p1 <- ggplot(df, aes(x=dose, y=len, color=factor(supp))) +
geom_line(aes(group = supp)) +
theme(
plot.title = element_text(hjust = 0.5),
panel.background = element_rect(fill = "#140F4B",
colour = "#140F4B",
size = 0.5, linetype = "solid"),
panel.grid.major = element_blank(),
panel.grid.minor = element_blank(),
plot.background = element_rect(fill = "#140F4B"),
text = element_text(colour = "white"),
axis.line = element_line(colour = "white"),
axis.text = element_text(colour = "white")
) +
scale_color_manual(values = cols,
name = "supp",
breaks=c("VC", "OJ"),
labels=c("VC", "OJ"))
p2 <- ggplot(df, aes(x=dose, y=len, color=factor(supp))) +
geom_line(aes(group = supp)) +
theme(
plot.title = element_text(hjust = 0.5),
panel.background = element_rect(fill = "#140F4B",
colour = "#140F4B",
size = 0.5, linetype = "solid"),
panel.grid.major = element_blank(),
panel.grid.minor = element_blank(),
plot.background = element_rect(fill = "#140F4B"),
text = element_text(colour = "white"),
axis.line = element_line(colour = "white"),
axis.text = element_text(colour = "white")
) +
scale_color_manual(values = cols,
name = "supp",
breaks=c("VC", "OJ"),
labels=c("VC", "OJ"))
combined <- p1 + p2 + plot_annotation(title = "Title Here") +
plot_layout(guides = "collect") &
theme(plot.title = element_text(colour = "white", size = 18), legend.position = "bottom",
legend.background = element_rect(fill = "#140F4B", colour = "#140F4B" ),
legend.key = element_rect(fill = "#140F4B", colour = "#140F4B" ),
plot.background = element_rect(fill = "#140F4B", colour = "#140F4B"))
combined