Generating color palettes for design systems … inspired by APCA!

This is the first of two blog posts about how we created the color palette for a new design system at Canonical. In this post I share my journey into perceptually uniform color spaces and perceptual contrast algorithms.  If you’re already familiar with these concepts, skip to this section (or visit the Github repository) to see how I reverse-engineered the Accessible Perceptual Contrast Algorithm (APCA) to generate perceptually contrasting color palettes. In the next post, I will share […]

https://www.ubuntu-server.com/ubuntu/generating-color-palettes-for-design-systems-inspired-by-apca/

زهرة الخليج – فلاتر جديدة من Dior احتفاء بشهر رمضان المبارك

https://todaypic.net/entertainment/150177/

زهرة الخليج – فلاتر جديدة من Dior احتفاء بشهر رمضان المبارك

#أخبار الموضة زهرة الخليج اليوم في رمضان، كشفت ديور عن مجموعة من الفلاتر التي تعكس مصدر إلهام كبسولة «ديور أور» التي حلمت بتصميمها ماريا غراتسيا كيوري. فلاتر جديدة من Dior احتفاء…

For the "it's the law tho" crowd, here's a fix:

APCA to WCAG 2 Backwards Compatibility Chart

For 4.5:1

Backwards 4.5:1 is achieved when:

IF the lightest color is darker than #d0d0d0
OR the darkest is darker than #595959
THEN Lc ±60 exceeds 4.5:1

ELSE Lc 72 or Lc -77 exceeds 4.5:1 in all cases

---
For 3:1

Backwards 3:1 is achieved when:

IF the lightest color is darker than #c4c4c4
OR the darkest is darker than #6c6c6c
THEN Lc ±45 exceeds 3:1

ELSE Lc 57 or Lc -63 exceeds 3:1 in all cases

---
Here's the implication:

If both colors are darker than #d0d0d0 or at least one is darker than #595959:

Then it's not a matter of "can you?" use APCA, it's a matter of you *should* use APCA.

For color pairs darker than #d0d0d0, WCAG 2.x contrast math results are not meaningful, and create inaccessible, often unreadable, color pairs.

Actual Accessibility is where it's at.

#darkmode #Webdesign
#a11y #color #webdev
#colour #wcag #apca

背景が#383838, 文字が#c4c4c4 なのでコントラストがフルレンジの半分くらいしかない。
Macのメニューバーは背景#000000、文字が#e8e8e8 なので、Unityの文字に画面のコントラストを合わせると他のアプリたちの文字がギラギラしすぎる。
Writefreely CSS formatting tips and tricks

Writefreely is the platform this blog runs on. One of the features of Writefreely is the ability to add custom CSS to your blog. They hav...

Stimrant Central
Base Color : F73662
Mode : monochrome-dark
#A30A2D
#C60C36
#E90D3F
#F42756
#A0A0A0
#B2B2B2
#C4C4C4
Base Color : 7AC2B9
Mode : monochrome-dark
#3E7F77
#4DA298
#69B9AF
#ABABAB
#C4C4C4
Base Color : 8E96E7
Mode : monochrome-dark
#2E3CC7
#4552D5
#626DDC
#7F88E4
#C4C4C4
#D6D6D6
#E8E8E8