diff --git a/lua/avante/highlights.lua b/lua/avante/highlights.lua
index 44a954a..621d932 100644
--- a/lua/avante/highlights.lua
+++ b/lua/avante/highlights.lua
@@ -124,11 +124,12 @@ H.alter = function(attr, percent) return math.floor(attr * (100 + percent) / 100
 
 ---@source https://stackoverflow.com/q/5560248
 ---@see https://stackoverflow.com/a/37797380
----Darken a specified hex color
+---Lighten a specified hex color
 ---@param color number
 ---@param percent number
 ---@return string
 H.shade_color = function(color, percent)
+  percent = vim.opt.background:get() == "light" and percent / 10 or percent
   local rgb = H.decode_24bit_rgb(color)
   if not rgb.r or not rgb.g or not rgb.b then return "NONE" end
   local r, g, b = H.alter(rgb.r, percent), H.alter(rgb.g, percent), H.alter(rgb.b, percent)