I am begging website owners to always provide a light mode. It’s an accessibility issue for me: my aging eyes are no longer able to view light-on-dark text for extended periods without severe ghosting/afterimages.

#accessibility #website #design

@drahardja YES! I have astigmatism so it makes light on dark immensely hard and uncomfortable to read unless I bump up the text size 😭
@ghalldev @drahardja Is it important to have a toggle, or does making it respect the system theme almost always work?
@sashin @ghalldev Either would be fine, since I keep my system in Light mode.

@ghalldev @drahardja That’s so curious. I too have astigmatism and need reading glasses but I find light backgrounds extremely uncomfortable on the eyes.

Dark mode has been a god send to me. I don’t like white on black - I use dark grey and some very light shade of grey, and on my kobo I use a yellow tint.

I have trouble with brightness in general and wear transitions lenses, or very dark sunglasses when the day is too bright. That may be the reason the light mode bothers me so much.

@catzilla @drahardja That is interesting re: brightness, I have the opposite problem I have trouble in the dark and I never wear sunglasses.

Oddly I will occasionally switch to dark mode if it’s a rainy day because I get headaches. 😅

Eyes are weird.

@drahardja Very much in the same boat - the ghosting started getting impossible to ignore a few years ago, and the time needed to induce it has continued to shrink.
@drahardja Despite its name, dark reader has an invert option so you can easily and quickly force a light mode on sites that lack one.

@drahardja
Wouldn't it also be great if there were a tool, in the browser that let you control screen colors better.... ie change the tint of all the pages...

I use dislexia reading colors, to tone the screen down, when I get bleery in the night. My workaround is macos accessability> display> colors.

I built my own icc profile that is in HSV color space, and for the choice, I made a pallate that has hue 0-360 by 5's.

I don't know how to share export it or where to find it, where it lives. so I can share it out. Tell me that, and you are first.

@drahardja Here’s what I wrote when I added automatic light mode support to my blog:

“This is something that improves accessibility, but there's also a practical reason: I myself use light mode. Like many folks with astigmatism, I find dark mode more difficult to read. […] I want a blog I can actually read even when my eyes get tired. And if it bothers me, there are almost certainly other people it bothers as well.”

https://arjache.com/2025/06/light-theme/

Blog housekeeping

I've added a light theme to the blog's CSS which should be automatically selected if your system is set to use light mode. The original dark theme will be selected if your system is set to use dark mode. ...

badger trebuchet diagram no. 17

@drahardja

I also take bilberry... it's supposed to help night vision, it has a myth, look it up.

I shouldn't have to say this, but you may also want to cut own on the hallucinigenics if that's a thing for you.

@drahardja

Maybe it's a sign that you need to put the screen away and read a book. Or Migrains.

Me too, I have this. including the age thing.

@drahardja Yes, yes, yes! Beginning cataracts give me double images. White on black text requires a huge effort.

@drahardja

Oh huh, maybe that's why I prefer light mode. I did not know that about astigmatism, thank you.

@drahardja i have to use reader mode and if that's not available i'll try to set "page style > no style" in firefox and if that doesn't do it i just can't read it
@drahardja I always use dark mode, but override it with my own settings on probably 90% of sites that offer their own, because nearly all of them use white text on dark (or black) background, which is way too high contrast for me.

@drahardja
Heya Dave, I design a lot of websites and apps for my work. We usually design them for dark mode first, which means we often have design oversights in the light versions.

Are there any things we should keep in mind to make sure that the light versions are accessible to people like you?

@VanuPhantom I’m sure light-on-dark design has been discussed extensively since the days of print. I’m not a usability expert, but I can tell you what affects me personally.

I’m most sensitive to anything that look like bars: repeating strips of high contrast light against dark, like prison cell bars in old cartoons; these patterns cause severe afterimages, often lasting minutes.

My pet theory is that *light areas* in general cause afterimages for me overall. However, in light mode, the entire window is light, so it makes less difference because I basically get a diffuse, white-rectangle afterimage which doesn’t really interfere with details that I’m trying to focus on (it may reduce contrast somewhat in my brain but it’s fine). But in dark mode, the only bright things that cause afterimages are the fine detail (text), so as I move around these afterimages interfere severely against the new details I’m trying to read. A similar thing happens with bars when I’m in light mode.

@VanuPhantom Body text fonts matter too. A font with tall counters and good variation between characters are easier to read for me. For serifs, I don’t like fonts that have very thin parts (e.g. Bodoni) for text because they tend to make the thicker parts look like bars. I prefer fonts like Schoolbook that have more modest thick/thin contrast, or Adelle that has basically uniform line widths.
@drahardja My website is so old I haven't got around to adding a dark mode yet, you're fine.

@drahardja

IMHO, every modern website should support both modes.

In my case, it's the light mode that my aging eyes can no longer tolerate (too bright: my eyes tire quickly).
And while many rightly criticize dark mode for too much contrast between white text and a black background, for me, it's the lack of contrast that too often prevents me from reading without resorting to manual zoom.

@drahardja

Fortunately, today's CSS and `light-dark()` make supporting user preferences much easier than before.

However, while WCAG2 and APCA allow us to verify that the contrast is sufficient, what are the recommendations regarding excessive contrast?

@drahardja til I am not the only one this happens to
@drahardja Thanks so much for that post. I have the same problem.
@drahardja 2c: the web browser should manage this.

@dannyman I mean, it does to an extent. CSS has the color-scheme and light-dark() colors that respond to the browser’s settings.

But the browser can only do so much. CSS doesn’t convey the *intent* of elements, only their *appearance*. It’s much worse with React-style pages, in which the CSS *and* html elements have basically zero semantic meaning.

I use Reader mode to get around dark mode, which works sometimes for sites with mostly static blog contents, but a wholesale rewriting of the page style basically requires reading the minds of the developers.

@drahardja so ... HTML is fundamentally semantic ... there are a bunch of words that you want to read and some markup explaining how the author wants it to render ... but what happens on the clients side is fundamentally up to the client ... to represent the words ... that's why blind folks can browse the web with screen readers -- it's just words -- and you ought to be able to access a web browser that can cater to your own abilities as well.

This is more reliable than asking millions of random web sites to somehow understand every nuance of crafting CSS for each audience.

I believe the mainstream operating systems and web browsers already have a variety of accessibility settings, each frustratingly limited in its own way. We all know how to crank the font size up and down!

(Personally, I tend to avoid web sites that DON'T support a dark mode, which I find easier to read, but not to a degree that I need an accommodation. Kagi slow web has a neat switch for rendering random sites in light/dark mode.)

@dannyman HTML *can* be semantic, but only if the web developer cared. Many websites now use an intermediary framework like React that renders everything as divs, without any further meaning.

Some websites are considerate enough to use semantic tags like <article> but this is by no means universal, or even widespread in my experience.

@drahardja

Nah, that's not React's fault. That's developer's. You can use semantic HTML in react as well.

@dannyman

@drahardja I have a similar problem in Zoom meetings. They have changed the chat box to dark mode, and Zoom keeps recommending ways to change it back to light mode that just don't work on my computer.
@drahardja
I'm far from expert at web stuff. But I will try to implement this on my sites.
@drahardja and also light-on-dark because some folk have so many floaters it's not worth the effort of reading in light mode.
@drahardja

I often find the opposite, UK anyway, been fighting the bank for years to get a Dark Mode for example.
I struggle with light mode (Photosensitivity) and am partially dyslexic.
I have ageing eyes anyway, surprised I don't get the issue you mention.
@drahardja

I will always loudly advocate for every site to support both, default to the user's setting, and have a prominent control to switch theme.