How do I centre the popup?

[Ajaymamtora]

This is my config, I can't figure out how to make the popup appear in the middle of the editor like hydra

local options = {
  presets = "modern",
  plugins = {
    marks = true,
    registers = true,
    presets = {
      operators = true,
      motions = true,
      text_objects = true,
      windows = true,
      nav = true,
      z = false,
      g = true,
    },
    spelling = {
      enabled = false,
      suggestions = 20,
    },
  },
  icons = {
    breadcrumb = "»",
    separator = "➜",
    group = "+",
  },
  win = {
    width = { max = 70 },
    -- don't allow the popup to overlap with the cursor
    no_overlap = true,
    -- width = 1,
    -- height = { min = 4, max = 25 },
    -- col = 0,
    -- row = math.huge,
    border = "single",
    padding = { 1, 2 }, -- extra window padding [top/bottom, right/left]
    title = true,
    title_pos = "center",
    zindex = 1000,
    -- Additional vim.wo and vim.bo options
    bo = {},
    wo = {
      -- winblend = 10, -- value between 0-100 0 for fully opaque and 100 for fully transparent
    },
  },
  layout = {
    width = { min = 20 }, -- min and max width of the columns
    spacing = 3, -- spacing between columns
  },
  show_help = true,
  -- list of triggers, where WhichKey should not wait for timeoutlen and show immediately
  delay = function(ctx)
    local nowait = {
      -- marks
      "`",
      "'",
      "g`",
      "g'",
      -- registers
      '"',
      "",
      -- spelling
      "z=",
      ";",
    }

    for _, v in ipairs(nowait) do
      if ctx.keys == v then
        return 0
      end
    end

    return 400
  end,
  debug = false, -- enable wk.log in the current directory
}

[Ajaymamtora]

opts.win.col = 0.5