I've read a paper (and I can confirm that) that reading black on white is worse for the eyes, after a full working day on PC i wish I could read "dark" pages. In Samsung and Firefox browser one can use "inverted color" mode, where the background of the pages is automatically switched to a black color and other colors are updated accordingly.
So my request is: add an option to the night mode (or to the general options) to show page colors inverted, or in a "white text on dark background" mode. This would be really great.

@leocg : I don't want a blue or whatever filter on my tablet, it will affect all aps and most of them would break. I just want inverted reading mode for web pages in Opera.

@treego, extension is for desktop Opera, bit I mean Android version.

Thanks for thinking on Night mode, but the feature is not complete. Night mode schould dim/invert colors not only for the browser UI, bit for the whole page. What brings me a "darker" toolbar strip on a web page with bright white background? Right, nothing. So please, implement full night mode, like for example in the Samsung browser, where the bright colorscon pages are dimmed and we have white text on black background.

Yep, inverted colors: white text on black background. Samsung browser does this, also many Firefox addons. I really need this in Opera.

I've read a paper (and I can confirm that) that reading black on white is worse for the eyes, after a full working day on PC i wish I could read "dark" pages. In Samsung and Firefox browser one can use "inverted color" mode, where the background of the pages is automatically switched to a black color and other colors are updated accordingly.
So my request is: add an option to the night mode (or to the general options) to show page colors inverted, or in a "white text on dark background" mode. This would be really great.