Field Notes

Design kit

Clean, not overwhelming, opinionated. One typeface, one accent, plenty of room. Hierarchy comes from size and space — not heavy weights or extra colour.

Principles

  • Monospace voice. One typeface everywhere — it reads precise, technical, and calm.
  • One accent. A single green, used sparingly — links, labels, the line that matters. Everything else is ink on paper.
  • Hairlines and air. Thin borders, white cards on warm paper, generous whitespace. No gradients, no shadows, no clutter.
  • Size and space over weight. Regular and medium carry the text; semibold marks headings and labels, with bold reserved for subsection headings. Scale and spacing still do most of the hierarchy.
  • Drafting-paper framing. Dashed hairlines frame the text column and divide sections; figures get corner brackets. Corners stay square — buttons and cards included. Structure you can feel, not decoration.
  • Plainspoken and precise. Short, declarative sentences in plain English — no hype, no jargon, no exclamation marks. Always speak to "you," and never call Felix "it." Calm, confident, opinionated: say what's true and let the words stand.

Logomark

Top-right and bottom-left corner brackets framing a single focus square — the drafting-paper frame distilled to a mark, drawn entirely in the green accent. It always pairs to the left of the "Felix" wordmark.

Felix
Favicon — single green, no tile, brightens on dark tabs
Light · #0F6E56
Dark · #16A07D
Construction & usage
  • One colour throughout — brackets and focus square are the same green accent. Never recolour it or split it into two tones.
  • Square corners, square line caps. No rounding, no gradient, no container tile.
  • The favicon zooms in — tighter padding, heavier stroke, a single colour — so it stays legible at 16px and lifts to the brighter green on dark tabs.
  • Keep clear space around the mark at least the length of a bracket arm; set it tight to the wordmark but never overlapping.
Direction — the mark as an up/down signal

Up is green with brackets top-right + bottom-left (the "/" diagonal); down is red with brackets top-left + bottom-right (the "\" diagonal). The diagonal carries the meaning, colour reinforces it — so always pair the mark with a signed value, since at small sizes colour does most of the work.

+2.4%
−1.8%
AAPLApple Inc.+0.8%
INFYInfosys Ltd.−1.2%
NVDANVIDIA Corp.+3.1%

Colour

Paper
#FBFAF6
Background
Ink
#1B1B18
Primary text
Muted
#6E6D64
Secondary text
Faint
#9A988D
Captions, hints
Green
#0F6E56
Accent — links, highlights
Green deep
#0A4A3A
Text on tint, emphasis
Green bright
#16A07D
Dark-mode accent (favicon)
Red
#B23A2C
Loss / downward
Tint
#EAF3EF
Green surfaces
Line
#E5E2D7
Hairline borders
Line tint
#CAE1D8
Hairlines on green
Bracket
#CBC8BD
Corner brackets
Surfaces
PaperPage background
WhiteAlternating section bands
TintFooter & callouts
CodeInline code

Typography

JetBrains Mono — regular (400) and medium (500) for text, semibold (600) for headings and labels, bold (700) for subsection headings. System monospace as fallback.

Display / H1 · 34px
Felix
Section label · 12px
The problem
Subsection · 11.5px
Data model
Sub-label · subtle
Construction & usage
Body · 14px
Felix sees everything you own and tells you what to do.
Emphasis · 500
Advice, not automation.
Caption · 12px
Informational product concept.
Inline code
SourceAdapter

Components

Buttons
Tag & link
Advisory onlyIncognitoView recommendation
Card

One complete picture

Every account in a single, daily-updated net-worth view.

Callout
Holdings sync slowly; prices re-mark nightly. The dashboard is fresh every day.
Lines
Accent rule — header → body
Dashed divider — frames the column, separates sections
Framing
Corner-bracketed figure