Atom One Light
Atom's signature light theme — a near-white canvas (hue 230, sat 1%, lightness 98%) with eight accents tuned for syntax highlighting (cyan, blue, purple, green, two reds, two oranges). The companion to One Dark; designed for daytime reading. Light mode is sourced directly from one-light-syntax/styles/colors.less. Dark mode is brand-atoms' authored inversion (upstream ships light-only).
16 swatches 14 light roles 14 dark roles
Swatches
syntax-bg
#FAFAFA
Light canvas — syntax-hue 230, sat 1%, L 98%.
mono-1
#383A42
Default foreground / primary text on light.
mono-2
#696C77
Secondary text.
mono-3
#A0A1A7
Tertiary text / comments.
hue-1
#0184BC
Cyan accent — support, regex.
hue-2
#4078F2
Blue accent — functions / primary.
hue-3
#A626A4
Purple accent — keywords.
hue-4
#50A14F
Green accent — strings / success.
hue-5
#E45649
Red accent — variables / error.
hue-5-2
#CA1243
Deeper red accent.
hue-6
#B76B01
Orange accent — numbers / constants.
hue-6-2
#CB7701
Yellow-orange accent — types / warnings.
syntax-accent
#526FFF
Cursor / focus accent.
dark-canvas
#1C1D21
Authored dark bg — syntax-hue collapsed to L=12%.
dark-surface
#26272C
Authored dark surface — syntax-hue at L=16%.
dark-elevated
#2F3037
Authored dark elevated — syntax-hue at L=20%.
Mode role mappings
Light mode (14 roles)
accent
→ hue-3 accent-hover
→ hue-4 background
→ syntax-bg error
→ hue-5 primary
→ hue-2 primary-hover
→ hue-1 success
→ hue-4 surface
→ syntax-bg surface-elevated
→ mono-3 text-primary
→ mono-1 text-secondary
→ mono-2 text-tertiary
→ mono-3 warning
→ hue-6 warning-hover
→ hue-6-2 Dark mode (14 roles)
accent
→ hue-3 accent-hover
→ hue-4 background
→ dark-canvas error
→ hue-5 primary
→ hue-2 primary-hover
→ hue-1 success
→ hue-4 surface
→ dark-surface surface-elevated
→ dark-elevated text-primary
→ syntax-bg text-secondary
→ mono-3 text-tertiary
→ mono-2 warning
→ hue-6 warning-hover
→ hue-6-2 Provenance
- Source
- https://github.com/atom/atom/blob/master/packages/one-light-syntax/styles/colors.less
- License
MIT- Attribution
- Atom One Light by GitHub (atom is archived) — github.com/atom/atom
- Imported
-
2026-05-17 - Notes
- Light-mode hex values computed from the HSL definitions in one-light-syntax/styles/colors.less (syntax-hue 230, syntax-saturation 1%, syntax-brightness 98%; mono and hue values per the upstream @-vars). The atom/ atom repo is archived; the one-light-ui colors.less referenced in the source-of-truth path no longer exists at that path, so we sourced from one-light-syntax (canonical and stable). Dark mode is brand-atoms' authored inversion; upstream One Light ships light-only. Accent hex values are preserved unchanged across modes (accents are mode-stable per One Light's design intent). The dark canvas tones (dark-canvas, dark-surface, dark-elevated) are derived by collapsing lightness on the syntax-hue (230, 8%) to 12% / 16% / 20% — a clean cool-dark cast that mirrors the light canvas's hue family.