---

name: darkmatter-css

description: Use when building any web UI for Steve - applies his personal dark aesthetic with Commit Mono font, #121113 background, white borders, minimal layout, and max-width centered content. Use for new pages, components, or when asked to match his existing style.

---

# Darkmatter CSS

## Overview

Steve's personal web aesthetic: dark, minimal, monospace. No frameworks, no decorative flourishes. Everything is functional and stark.

## Core Palette

| Token | Value | Usage |

|-------|-------|-------|

| Background | `#121113` | All surfaces — html, inputs, buttons, textarea |

| Foreground | `#ffffff` | All text and borders |

| Border | `1px solid white` | Inputs, buttons, textarea |

| Gray Dark | `#1e1c1f` | Code block backgrounds |

| Gray Mid | `#333` | Dividers, list item borders, section separators |

| Gray Light | `#555` | Tertiary borders (blockquote borders) |

**No accent colors, no gradients.** Background, white, and grays only.

### Visual Hierarchy via Opacity (NOT gray color values)

Use opacity on white text instead of gray hex colors for secondary/tertiary text:

| Level | Opacity | Usage |

|-------|---------|-------|

| Primary | 1.0 | Headings, body text, links |

| Secondary | 0.7 | Labels, form labels, blockquotes |

| Tertiary | 0.5 | Nav links dimmed, table headers, dates, metadata, empty states |

| Muted | 0.3 | Null/placeholder values |

| Error | 0.8 | Error messages |

**Do NOT use `color: #888` for secondary text.** Always use `opacity` on white text instead.

## Typography

- **Font:** `"Commit Mono"` (self-hosted .otf), fallback `monospace, sans-serif`

- Applied globally via `* { font-family: ... }`

- **Body font-size:** 14px

- **Line-height:** 1.6

### Font Size Scale

| Size | Usage |

|------|-------|

| 28px | Site logo/title (bold, uppercase) |

| 18px | Markdown h1 |

| 16px | Markdown h2, note/item titles, primary labels |

| 15px | Markdown h3 |

| 14px | Body text, inputs, buttons, markdown h4-h6 |

| 13px | Inline code, error messages |

| 12px | Nav links, form labels, metadata, dates, table headers, action links |

### Font Face Declarations

```css

@font-face {

  font-family: "Commit Mono";

  src: url("./assets/fonts/CommitMono-400-Regular.otf") format("opentype");

  font-weight: 400;

  font-style: normal;

}

@font-face {

  font-family: "Commit Mono";

  src: url("./assets/fonts/CommitMono-700-Regular.otf") format("opentype");

  font-weight: 700;

  font-style: normal;

}

```

## Base Reset

```css

* {

  padding: 0;

  margin: 0;

  box-sizing: border-box;

  font-family: "Commit Mono", monospace, sans-serif;

  scrollbar-width: none;

  -ms-overflow-style: none;

}

html {

  background: #121113;

  color: #ffffff;

  font-size: 14px;

  line-height: 1.6;

}

html::-webkit-scrollbar {

  display: none;

}

```

## Layout

Single-column, centered, max 700px wide. No top body padding — top spacing comes from header `margin-top`:

```css

body {

  display: flex;

  flex-direction: column;

  justify-content: start;

  align-items: start;

  gap: 1.5rem;

  min-height: 100vh;

  max-width: 700px;

  margin: auto;

  padding: 0 1rem;

}

@media (max-width: 480px) {

  body {

    padding: 1rem;

    gap: 1rem;

  }

}

```

## Header

The header uses a border-bottom separator and `margin-top: 2rem` for top spacing. The site title/logo is **always uppercase**, 28px bold:

```css

.header {

  display: flex;

  flex-direction: column;

  gap: 0.5rem;

  width: 100%;

  margin-top: 2rem;

  border-bottom: 1px solid #333;

  padding-bottom: 1rem;

}

.logo {

  font-size: 28px;

  font-weight: 700;

  text-decoration: none;

  text-transform: uppercase;

}

```

## Navigation Links

Compact gap, small font:

```css

.links {

  display: flex;

  align-items: center;

  gap: 0.75rem;

  font-size: 12px;

}

```

## Interactive Elements

All inputs, textareas, and buttons match the background — they blend into the surface with only a white border. **No border-radius**, padding uses `0.4rem 0.75rem`:

```css

input, textarea {

  background: #121113;

  color: #ffffff;

  border: 1px solid white;

  padding: 0.4rem 0.75rem;

  font-size: 14px;

  width: 100%;

  border-radius: 0;

}

textarea {

  min-height: 400px;

  resize: vertical;

}

button {

  background: #121113;

  color: #ffffff;

  padding: 0.4rem 0.75rem;

  border: 1px solid white;

  cursor: pointer;

  width: fit-content;

  font-size: 14px;

  border-radius: 0;

}

button:hover, a:hover {

  opacity: 0.7;

}

a {

  color: #ffffff;

  text-decoration: none;

}

```

## Labels

```css

label {

  font-size: 12px;

  opacity: 0.7;

}

```

## Errors

Use a left border accent, not a full box border:

```css

.error {

  color: #ffffff;

  border-left: 2px solid #ffffff;

  padding-left: 0.5rem;

  font-size: 13px;

  opacity: 0.8;

}

```

## List Items

Vertical stacking with bottom borders as dividers, 16px title size:

```css

.item-list {

  display: flex;

  flex-direction: column;

  width: 100%;

}

.item {

  display: flex;

  flex-direction: column;

  gap: 0.25rem;

  padding: 0.75rem 0;

  border-bottom: 1px solid #333;

}

.item:hover {

  opacity: 0.7;

}

.item-title {

  font-size: 16px;

}

.item-meta {

  font-size: 12px;

  opacity: 0.5;

}

```

## Table Headers

Uppercase, dimmed, lightweight:

```css

th {

  opacity: 0.5;

  font-weight: 400;

  font-size: 12px;

  text-transform: uppercase;

}

```

## Meta Tags

Always include:

```html

<meta name="theme-color" content="#121113" />

```

## What NOT to Do

- No `border-radius` — keep all corners sharp (explicitly set `border-radius: 0` on inputs/buttons)

- No box shadows or drop shadows

- No color other than `#121113`, `#ffffff`, and the gray tones (`#1e1c1f`, `#333`, `#555`)

- **No `color: #888`** — use `opacity` on white text for visual hierarchy instead

- No external font CDNs — fonts are self-hosted

- No utility frameworks (no Tailwind, no Bootstrap)

- No decorative elements, icons, or emojis