This method works for me perfect:
local scrX, scrY = guiGetScreenSize()
local devScreenY = 1024
local scale = math.min(math.max(scrY / devScreenY, 0.65), 2)
local parent_w = 600
local parent_h = 360
local parent_x = scrX / 2 - parent_w * scale / 2
local parent_y = scrY /2 - parent_h * scale / 2
addEventHandler("onClientRender", root, function()
dxDrawRectangle(parent_x, parent_y, parent_w * scale, parent_h * scale, tocolor(23, 23, 25))
dxDrawCircle(parent_x + (50) * scale, parent_y + (50) * scale, 50 * scale, 0, 360, tocolor(60, 80, 150))
end)