The Parameter Manual

Web design with the reasoning shown.

Eighteen parameters. Each one carries the rule, the mechanism behind it, the source, and the grade that source earns. This is the studio's long-form proof, and it is free.

How grades work

A claim is only as strong as what stands behind it.

A: Replicated. More than one independent study finds the effect.
B: Single study. One peer-reviewed source, not yet replicated.
C: Industry research. Large samples, commercial authorship.
D: Practitioner convention. Widely done, not measured.
N: Normative standard. An obligation, never cited as evidence.
X: No evidence found. The value is a decision and is labelled as one.

The eighteen

Identity, structure, surface, behaviour.

Parameter 07 is published in full. The rest are listed with their rule and grade; their articles follow, one a week.

The eighteen parameters with their rule, family, evidence grade and sources
#	Parameter · the rule	Family	Grade	Sources
01	Logo An abstract lettermark banks attribution; clear space one stroke width, minimum 24 px, never recoloured beyond three colourways.	Identity	B	Henderson & Cote 1998 · Fiocchi & Seyed Esfahani 2024
02	Colour Near-monochrome; the accent is an event, spent in three places. Semantic states are never colour alone.	Identity	B	Labrecque & Milne 2012 · WCAG 1.4.1
03	Typography Category-appropriateness beats face-superiority. Three faces, subset, self-hosted, zero unused families.	Identity	B	Doyle & Bottomley · Wallace 2022 (A)
04	Scale Ratio 1.250, nine steps and a statement size; body 16/1.55 on a 66-character measure.	Structure	A	Dyson & Haselgrove (B) · Nielsen
05	Layout Twelve columns, 24 px gap, three containers; hierarchy between sections by inversion, not accent.	Structure	B	Reinecke et al. (visual complexity)
06	Spacing A 4 px base, gap-first, so layouts survive editing and reordering.	Structure	C	Gestalt proximity · tokenised practice
07	Shape Radius 0. A corner is square or chamfered at 45°, top-right. Where the category rounds, we cut.	Surface	B	Jiang et al. 2016
08	Elevation Borders and inversion carry layering; one shadow recipe, for overlays only; boundaries ≥ 3:1.	Surface	C	WCAG 1.4.11 (N)
09	Buttons One system, three levels, 48 px targets, one primary action per view.	Structure	N	WCAG 2.5.8 · Fitts
10	Forms Boxed 1.5 px fields, labels above, validate on blur, errors as icon + text + border.	Structure	C	Baymard (abandonment)
11	Navigation Five items, sticky, current item marked; everything reachable in two clicks.	Structure	A	Landauer & Nachbar
12	Icons One grid, one stroke, one provenance; icons are always labelled.	Surface	B	Burmistrov (flat abstraction)
13	Imagery Real work at real fidelity; descriptive alt mandatory; decorative images alt empty.	Surface	B	Reinecke · Cyr (no direct trust path)
14	Texture None on light; a 3 % chamfer grid on dark only; static.	Surface	D	Practitioner convention
15	Motion 80 / 180 / 280 ms ease-out; one signature move; reduced-motion complete; no scroll-jacking, no cursor.	Behaviour	A	Nielsen limits · WCAG 2.3.3 (N)
16	Voice Outcome-first H1 bank; mono micro-labels; no metric without its project.	Identity	C	Nielsen 2008 (20 % of words read)
17	Conversion A ladder, not a leap: See → Read → Start. Published flat price; proof beside the ask, bound per project.	Behaviour	A	You et al. (rating valence) · Baymard (C)
18	Accessibility & performance WCAG 2.2 AA with a published statement; LCP ≤ 2.0 s, INP ≤ 200 ms, CLS ≤ 0.05 at p75; fonts ≤ 160 KB.	Behaviour	N	WCAG 2.2 · Core Web Vitals · WebAIM 2026 (C)