r - scale_edge_colour_gradient 图例未完全填充颜色

Question

看来我的颜色键图例没有完全填充颜色（即在这种情况下一直到 1）。此外，我试图将键标题（即链接强度）放在键的顶部而不是左侧。

ggraph(lay.ggraph) + 
 geom_edge_link0(aes(edge_colour = links$weight),
  edge_width = links$weight*10, lineend = "round") +
 scale_edge_color_gradient(name = "Link Strength",
  low = "#6495ED85", high = "#C1403D85") +
 geom_node_point(shape = 21, fill = "#D3D3D3", color = "#808080",
  size = 15, stroke = 2) +
 labs(y = "TL") +
 foodweb_theme`