How to change tabline "empty space" color, and get winbar & statusline to obey StatusLineNC highlight?

[barries]

I'm using the "auto" theme config and, unlike what it does for the winbar, lualine colors the "empty" part of the tabline; I'd like to de-emphasize it (I use this bright green to indicate the currently selected / focused window).

How can I change that fill color?

And how can I change the winbar and statusline components and empty space to follow the StatusLineNC highlight for non-current windows. I don't want colors per mode--there are so many modes and colors that they have no specific meanings for me and become visual noise, and cursor shape & color work for me, especially because and that's where my eyes are when editing)?

Many thanks!!! And thanks for the amazing plugin!

Here are the relevant vim highlights; lualine seems to be ignoring StatusLineNC:

hi StatusLine     cterm=NONE     gui=NONE       ctermfg=Black  guifg=#000000  ctermbg=118  guibg=#87ff00
hi StatusLineNC   cterm=NONE     gui=NONE       ctermfg=Black  guifg=#000000  ctermbg=246  guibg=#949494

Here's my config so far:

    {
        dir = "~/github/lualine.nvim",
        dependencies = { "nvim-tree/nvim-web-devicons", "SmiteshP/nvim-navic" },
        opts = function()
            local empty_separators = { left = "", right = "" };

            local winbar = {
                lualine_a = {
                    {
                        "filename",
                        path = 1, -- 1: relative path
                        color = "StatusLine",
                        fmt = function(s)
                            -- "<filename> <readonly>?<saved>"
                            local s1 = s:gsub(" %[%+%]", "")
                            local modified = (#s1 ~= #s)
                            local s2 = s1:gsub(" %[%-%]", "")
                            local readonly = (#s2 ~= #s1)
                            return s2
                                .. " "
                                .. (readonly and "%5*%*" or "")
                                .. (modified and "%4*•%*" or " ")
                        end,
                    }
                },
                lualine_b = {
                    {
                        "diagnostics",
                        always_visible = true,
                        sources = { 'nvim_diagnostic' },
                        on_click = function() Snacks.picker.diagnostics() end,
                        fmt = function(s)
                            local buffer_has_lsp = #vim.lsp.get_clients({ bufnr = 0 }) > 0;
                            if buffer_has_lsp then
                                if s:find(" 0 ") then
                                    if #vim.lsp.status() > 0 then
                                        local spinners = { "⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧", "⠇", "⠏" };
                                        local ms = vim.loop.hrtime() / 1000000;
                                        local frame = math.floor(ms / 120) % #spinners;
                                        local replacement = spinners[frame + 1];
                                        return s:gsub(" %d ", " " .. replacement .. " "):gsub(" %d$", " " .. replacement)
                                    else
                                      return s:gsub(" 0 ", " · "):gsub(" 0$", " ·")
                                    end
                                end
                            end
                            return " ";
                        end,
                    },
                },
                lualine_c = {
                    {
                        "navic",
                        color = {
                            bg = "Black",
                        },
                    },
                },
                lualine_x = {},
                lualine_y = {},
                lualine_z = {},
            };

            local tabline = {
                lualine_a = {
                    {
                        "tabs",
                    }
                },
                lualine_b = {
                    {
                        function()
                            if #vim.lsp.status() > 0 then
                                return require('lsp-progress').progress();
                            end
                            return " ";
                        end,
                        color = {
                            fg = "LightGreen",
                            bg = "Black",
                        },
                    }
                },
                lualine_c = {},
                lualine_x = {},
                lualine_y = {},
                lualine_z = {},
            };

            local function handle_fileinfo_click()
                vim.notify(
                       "fileformat:   " .. vim.bo.fileformat          .. "\n"
                    .. "filetype:     " .. vim.bo.filetype            .. "\n"
                    .. "fileencoding: " .. vim.bo.fileencoding        .. "\n"
                    .. "\n"
                    .. "shiftwidth:   " .. vim.bo.shiftwidth          .. "\n"
                    .. "tabstop:      " .. vim.bo.tabstop             .. "\n"
                    .. "expandtab:    " .. tostring(vim.bo.expandtab) .. "\n"
                    .. "textwidth:    " .. vim.bo.textwidth
                );
            end;

            local statusline = {
                lualine_a = {},
                lualine_b = {},
                lualine_c = {},
                lualine_x = {},
                lualine_y = {},
                lualine_z = {
                    "diff",
                    {
                        function()
                            local warnings = {};
                            local enc = (vim.bo.fenc or vim.go.enc);
                            if enc ~= "utf-8" then
                                table.insert(warnings, enc);
                            end

                            local fmt = "" .. vim.bo.fileformat;
                            if fmt ~= "unix" then
                                table.insert(warnings, fmt);
                            end

                            return table.concat(warnings, " ");
                        end,
                        color = { bg = "Orange" },
                        on_click = handle_fileinfo_click,
                    },
                    {
                        "location",
                        on_click = handle_fileinfo_click,
                    },
                },
            };

            return {
                options = {
                    icons_enabled = true,
                    theme = "auto",
                    component_separators = empty_separators, -- work around tabline attempt to concat nil val
                    section_separators = empty_separators,
                    disabled_filetypes = {
                        statusline = {},
                        winbar = {},
                    },
                    ignore_focus = {},
                    always_divide_middle = true,
                    always_show_tabline = true,
                    globalstatus = false,
                    refresh = {
                        statusline = 100,
                        tabline = 100,
                        winbar = 100,
                    }
                },
                sections          = statusline,
                inactive_sections = statusline,
                tabline           = tabline,
                winbar            = winbar,
                inactive_winbar   = winbar,
                extensions        = {}
            }
        end,
    },

[octogun89mm]

I have the same problem here, I used the same approach as you except I use buffers in the tabline instead of actual tabs, it still follows the general theme (same as the status bar).
We're probably missing something very important.