Katae

lpanels:CreateLayout("Test", {
    -- Your original black bar panel
    {   name = "BlackBar",
        anchor_to = "top", y_off = 0,
        width = "100%", height = 22,
        bg_color = "0 0 0", bg_alpha = 0.4,
    },

    -- Your new 1 pixel borders, first on the top, second on the bottom of BlackBar
    {   name = "BorderBottom",
        anchor_to = "BOTTOM",
        width = "100%", height = 1,
        bg_color = "CLASS", bg_alpha = 0.75,
    }
})
lpanels:ApplyLayout(nil, "Test")