Colour scheme proposals — lifting the primary (2026-10-09)
Status: Draft · Date: 2026-10-09 · Owner: "I am still not sure about our primary colour because it seems to drag the whole thing down with the dark, toned-down green. Propose a few colour schemes that would fit the audience and the theme of the app well." Audience: Korean amateur tennis club members and the 총무 who run the club (30s–50s, dues, schedules, rosters). Theme: court sport, club life, the ball. Numbers from the shared helper (CIELAB, WCAG 2.x, APCA, ΔE2000, Machado CVD); market hexes from the benchmark lanes.
1. Why the green drags
| Primary | L* | C* | white on it | ink on it |
|---|---|---|---|---|
ours #006D37 | 39.9 | 46 | 6.48 | 2.95 |
Toss #3182F6 | 55.3 | 67 | 3.71 | 5.15 |
당근 #FF6600 | 62.3 | 90 | 2.94 | 6.52 |
Naver #03C75A | 70.6 | 78 | 2.25 | 8.49 |
Band #4FC962 | 72.4 | 69 | 2.13 | 8.99 |
배민 #2AC1BC | 71.0 | 39 | 2.22 | 8.61 |
Kakao #FEE500 | 90.4 | 90 | 1.28 | 14.96 |
Playtomic #335FFF | 47.1 | 93 | 4.98 | 3.85 |
Korean primaries sit at L* 55–90 with C* 67–90; ours is L* 40 at C* 46 — darker and duller than every one of them, and it is the only colour we paint, so every block and button carries that weight. Green has a structural problem here: a green that keeps white text readable (≥ 4.5:1) cannot be lighter than L* ≈ 48–50 (#0F8446 4.76:1), so "lifting" it buys 8 L*; a fresh green (L* 68–75, ink text) is ΔE 4–6 from Naver and Band — it is their colour. Blue, clay and ball-yellow do not have this ceiling.
2. Four schemes (all keep the colour budget: one brand action + one block per screen; semantic set from the ledger)
| S1 · Court Green, lifted | S2 · Ball & Ink | S3 · Hard-Court Blue & Ball | S4 · Clay & Sand | |
|---|---|---|---|---|
| Primary (action: FAB, CTA) | #0F8446 white label (4.76:1) | ball #D6F04A with ink label #0D100E (14.96:1) | #2E5BE6 white label (5.59:1) | #C84F27 white label (4.56:1) |
| Block | #0F8446, white ink, optic progress | ink #15181A, ball-yellow numeral (Lc 90), labels white α0.8 | #2E5BE6, white ink, ball numeral accent | #C84F27, white ink |
| Links | #0F8446 underlined | ink, underlined | #2E5BE6 underlined | #C84F27 underlined |
| Level / today accent | optic #C6E84B | ball #D6F04A (one accent, one hue) | ball #D6F04A | ball #D6F04A |
| Neutral fill / hairline | #F0F5F1 / #CAD4CC (green-tinted, as today) | #F2F2F2 / #D4D4D4 (pure grey) | #F0F3F8 / #CCD3E0 (cool) | #F6F2EE / #D9D2CA (sand) |
| Where the brand green survives | everywhere (it is the primary) | logo, court-grass tile, nowhere else | logo, court-grass tile | logo, court-grass tile |
| Semantic set | unchanged (success teal, warning amber, error red) | unchanged | unchanged; $series1 (blue) re-derived (ΔE 7 from the primary) | error must move (clay vs error ΔE 10.5, 7.6 under deutan) → crimson #B3123E-class, re-gated |
| Market distance (ΔE2000) | Naver 21 · Band 22 · Toss 49 | Kakao 12 · 랠리업 same family (yellow on black) · Naver 23 | Toss 14 · 소모임 15 · Playtomic 3.6 — it is the category's blue · Ace / Baseline same family | 당근 14 · Strava 10 |
| L* / C* of the primary | 48 / 51 | 90 / 79 (ball) over ink 8 / 2 | 44 / 82 | 50 / 66 |
| Fit: audience | familiar, safe; still a dark fill | Kakao-familiar yellow-on-black for 30s–50s; premium ink like 무신사/크림; the most energetic | trust and order for 총무 (fintech blue); the racket category's own pair (Playtomic blue + lime) | warm, social, club-like; Strava energy |
| Fit: theme | grass court | the ball | hard court + ball | clay court |
| Risk | does not fix the weight (still L* 48); stays in the Naver/Band hue family | yellow needs ink text everywhere (no white-on-yellow); Kakao adjacency; block is dark by design (ink), lifted by the numeral | crowded blue; green identity reduced to the logo | collides with error semantics and 당근 orange; warm neutrals change every surface |
Rejected: a fresh green primary (#2EC26F-class, ink text) — ΔE 4–6 from Naver/Band; hard-court teal (#0B7E78) — C* 30, duller than today, the same complaint.
3. Recommendation
S2 Ball & Ink first, S3 Blue & Ball as the alternative. S2 is the only scheme that both lifts the page (the loudest colour is L* 90, the fills are ink or white) and owns something specific to tennis — the ball — while staying inside a pattern Koreans already read as mainstream (Kakao's yellow on black, 랠리업 in the category). It keeps the brand green as the mark and the court tile, so the identity is not lost, it is demoted from paint to signature. S3 is the safest for a 총무 audience and the category's proven pairing, at the cost of becoming another blue app. S1 is the minimum change and does not solve what you noticed. S4 is attractive but fights the error colour and 당근.
4. What the board shows
/wireframes/flat-v2 §G renders 홈 (block, rows, FAB) and 세션 상세 (hero, roster, CTA) in all four schemes at 1:1, with each scheme's swatch strip and the numbers above, so the choice is made on screens, not chips. Board checks (2026-10-09): block labels on S1/S3/S4 are drawn solid white because α0.8 falls under 4.5:1 there (3.6–4.2:1); S2's ball primary is 1.28:1 against the page, so its FAB/CTA edge is carried by the ink label (14.96:1), as Kakao's yellow buttons are. Question: "Which scheme — S1 / S2 / S3 / S4?"