Thanks, Choidebu.
Even though I am using Win10 Build 1803, somehow under 'Colours' setting it still gives me the option to choose between a 'light' mode and a 'dark' mode.
Unfortunately, this only switches the title bar/menu bar...etc of a window from ''black characters on white background'' to '' white characters on black background''. Also, as I use Firefox as my main browser, I discover that Firefox has a dark mode which does the same effect to the browser too.
This helps a little bit but I want to retain ''black characters on white background'' but with less light intensity, and not just for the title bar/menu bar...etc but for the entire monitor screen.
ASCii, may I ask, does the software f.lux only changes the colour warm and cool? Or, is it able to change the light intensity as well? I am really looking for the latter feature.
Actually, I am trying out Necere's suggestion and fiddle the monitor's built-in settings for preset modes. Among all the modes, there are 'Game' and Movie' modes which increases the monitor screen light intensity/brightness dramatically. This is, of course, opposite to what I am looking for. Then, there are modes for 'Warm' and 'Cool'. 'Warm' gives a yellowish look across the whole screen and 'Cool' gives a bluish look. Perhaps this kind of effect is more or less similar to what f.lux can do?
(This is certainly not a limitation of my monitor as it does not give me an over-brightness under Win 7.)