Typography

components/typography/heading/doc.ts

/**
 * Heading — a title in the document outline.
 *
 * ┌───────────────────────────────────────────────────────────────────────────┐
 * │ § CONTRACT — the oracle. Names no library, contains no code.              │
 * └───────────────────────────────────────────────────────────────────────────┘
 *
 * # Shape
 *
 *     level    1 | 2 | 3 | 4 | 5 | 6, REQUIRED
 *     size?    "sm" | "md" | "lg" | "xl" | "display"  default "md"
 *     …every attribute of a heading, and a ref
 *
 * # Behaviour
 *
 * R1  Renders h1–h6 from `level`. Level is required and independent of size,
 *     because the outline is not a visual decision.
 * R2  Sizes: sm `--text-15`, md `--text-heading` (22px where unset), lg
 *     `--text-30`, xl fluid between `--text-30` and `--text-42`,
 *     display fluid between `--text-42` and `--text-54` (a page's one headline).
 * R3  Set in `--font-display` (the sans face where unset) at
 *     `--heading-weight`, with tight leading and tracking.
 * R4  Long words break rather than overflow; lines are balanced.
 *
 * ┌───────────────────────────────────────────────────────────────────────────┐
 * │ § MECHANICS — NOT the oracle.                                             │
 * └───────────────────────────────────────────────────────────────────────────┘
 *
 * `--heading-weight` exists so v4 can set its display face at medium weight
 * without a preset-specific rule in any stylesheet.
 */
export {};

components/typography/heading/heading.tsx

import type { ComponentPropsWithRef } from "react";

import { cn } from "@/lib/utils/cn";
import { headingVariants, type HeadingVariants } from "./heading.variants";

export type HeadingProps = ComponentPropsWithRef<"h2"> &
  HeadingVariants & {
    /** The document outline position. Required, and independent of `size`:
     *  how big a heading looks is not where it sits in the outline. */
    level: 1 | 2 | 3 | 4 | 5 | 6;
  };

export function Heading({ level, size, className, ...props }: HeadingProps) {
  const Tag = `h${level}` as const;
  return (
    <Tag {...props} className={cn(headingVariants({ size }), className)} />
  );
}

components/typography/heading/heading.variants.ts

import { cva, type VariantProps } from "class-variance-authority";

import styles from "./heading.module.css";

export const headingVariants = cva(styles.root, {
  variants: {
    size: {
      sm: styles.sm,
      md: styles.md,
      lg: styles.lg,
      xl: styles.xl,
      display: styles.display,
    },
  },
  defaultVariants: { size: "md" },
});

export type HeadingVariants = VariantProps<typeof headingVariants>;

components/typography/heading/heading.module.css

@layer primitive {
  .root {
    margin: 0;
    color: var(--ink);
    font-family: var(--font-display, var(--font-sans));
    font-weight: var(--heading-weight, var(--weight-bold));
    line-height: var(--leading-tight);
    letter-spacing: var(--tracking-tight);
    overflow-wrap: anywhere;
    text-wrap: balance;
  }
  .sm {
    font-size: var(--text-15);
  }
  .md {
    font-size: var(--text-heading, var(--text-22));
  }
  .lg {
    font-size: var(--text-30);
  }
  .xl {
    font-size: clamp(var(--text-30), 4vw, var(--text-42));
  }
  /* A page's one headline: a hero, a coming-soon page. */
  .display {
    font-size: clamp(var(--text-42), 6vw, var(--text-54));
    letter-spacing: calc(var(--tracking-tight) * 1.5);
  }
}

components/typography/text/doc.ts

/**
 * Text — body copy.
 *
 * ┌───────────────────────────────────────────────────────────────────────────┐
 * │ § CONTRACT — the oracle. Names no library, contains no code.              │
 * └───────────────────────────────────────────────────────────────────────────┘
 *
 * # Shape
 *
 *     as?         "p" | "span" | "div"                            default "p"
 *     size?       "sm" | "md" | "lg"                              default "md"
 *     tone?       "default" | "muted" | "quiet" | "accent" | "crit"
 *     weight?     "regular" | "medium" | "strong"
 *     measure?    boolean — cap the line length at `--measure`
 *     truncate?   boolean — one line, ending in an ellipsis
 *
 * # Behaviour
 *
 * R1  md is `--text-body` (13px where unset), sm `--text-12`, lg `--text-15`,
 *     all at body leading.
 * R2  Tones map to `--ink`, `--ink-2`, `--ink-3`, `--accent`, and `--crit`.
 *     Tone is emphasis, never the only carrier of meaning.
 * R3  `truncate` hides overflow on one line; the full text stays in the DOM
 *     and is read in full by assistive technology.
 */
export {};

components/typography/text/text.tsx

import type { ComponentPropsWithRef } from "react";

import { cn } from "@/lib/utils/cn";
import { textVariants, type TextVariants } from "./text.variants";

export type TextProps = ComponentPropsWithRef<"p"> &
  TextVariants & {
    /** A paragraph by default; a span for text inside a line. */
    as?: "p" | "span" | "div";
  };

export function Text({
  as: Tag = "p",
  size,
  tone,
  weight,
  measure,
  truncate,
  className,
  ...props
}: TextProps) {
  return (
    <Tag
      {...props}
      className={cn(
        textVariants({ size, tone, weight, measure, truncate }),
        className,
      )}
    />
  );
}

components/typography/text/text.variants.ts

import { cva, type VariantProps } from "class-variance-authority";

import styles from "./text.module.css";

export const textVariants = cva(styles.root, {
  variants: {
    size: { sm: styles.sm, md: styles.md, lg: styles.lg },
    tone: {
      default: styles.default,
      muted: styles.muted,
      quiet: styles.quiet,
      accent: styles.accent,
      crit: styles.crit,
    },
    weight: {
      regular: styles.regular,
      medium: styles.medium,
      strong: styles.strong,
    },
    measure: { true: styles.measure },
    truncate: { true: styles.truncate },
  },
  defaultVariants: { size: "md", tone: "default", weight: "regular" },
});

export type TextVariants = VariantProps<typeof textVariants>;

components/typography/text/text.module.css

@layer primitive {
  .root {
    margin: 0;
    line-height: var(--leading-body);
  }
  .sm {
    font-size: var(--text-12);
  }
  .md {
    font-size: var(--text-body, var(--text-13));
  }
  .lg {
    font-size: var(--text-15);
  }
  .default {
    color: var(--ink);
  }
  .muted {
    color: var(--ink-2);
  }
  .quiet {
    color: var(--ink-3);
  }
  .accent {
    color: var(--accent);
  }
  .crit {
    color: var(--crit);
  }
  .regular {
    font-weight: var(--weight-regular);
  }
  .medium {
    font-weight: var(--weight-medium);
  }
  .strong {
    font-weight: var(--weight-strong);
  }
  .measure {
    max-width: var(--measure);
  }
  .truncate {
    display: block;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
}

components/typography/section-label/doc.ts

/**
 * SectionLabel — a small uppercase label above a heading or group.
 *
 * ┌───────────────────────────────────────────────────────────────────────────┐
 * │ § CONTRACT — the oracle. Names no library, contains no code.              │
 * └───────────────────────────────────────────────────────────────────────────┘
 *
 * # Shape
 *
 *     as?     "p" | "span"                default "p"
 *     tone?   "accent" | "quiet"          default "accent"
 *
 * # Behaviour
 *
 * R1  `--text-11`, bold, uppercase, `--tracking-label`.
 * R2  It is not a heading and does not enter the outline. Screen readers read
 *     it as plain text before the heading it sits above.
 */
export {};

components/typography/section-label/section-label.tsx

import type { ComponentPropsWithRef } from "react";

import { cn } from "@/lib/utils/cn";
import {
  sectionLabelVariants,
  type SectionLabelVariants,
} from "./section-label.variants";

export type SectionLabelProps = ComponentPropsWithRef<"p"> &
  SectionLabelVariants & {
    as?: "p" | "span";
  };

/** A small uppercase label above a heading or a group ("an eyebrow"). It is
 *  not a heading: it does not enter the document outline. */
export function SectionLabel({
  as: Tag = "p",
  tone,
  className,
  ...props
}: SectionLabelProps) {
  return (
    <Tag {...props} className={cn(sectionLabelVariants({ tone }), className)} />
  );
}

components/typography/section-label/section-label.variants.ts

import { cva, type VariantProps } from "class-variance-authority";

import styles from "./section-label.module.css";

export const sectionLabelVariants = cva(styles.root, {
  variants: { tone: { accent: styles.accent, quiet: styles.quiet } },
  defaultVariants: { tone: "accent" },
});

export type SectionLabelVariants = VariantProps<typeof sectionLabelVariants>;

components/typography/section-label/section-label.module.css

@layer primitive {
  .root {
    margin: 0;
    font-size: var(--text-11);
    font-weight: var(--weight-bold);
    line-height: var(--leading-snug);
    letter-spacing: var(--tracking-label);
    text-transform: uppercase;
  }
  .accent {
    color: var(--accent);
  }
  .quiet {
    color: var(--ink-3);
  }
}

components/typography/code/doc.ts

/**
 * Code — inline code.
 *
 * ┌───────────────────────────────────────────────────────────────────────────┐
 * │ § CONTRACT — the oracle. Names no library, contains no code.              │
 * └───────────────────────────────────────────────────────────────────────────┘
 *
 * # Behaviour
 *
 * R1  Monospace at 0.9em of the surrounding text, on `--surface-sunk` with a
 *     `--line` border, so it fits any line it sits in.
 * R2  Long identifiers break anywhere rather than overflow.
 * R3  Inline only. A block of code is a different component.
 */
export {};

components/typography/code/code.tsx

import type { ComponentPropsWithRef } from "react";

import { cn } from "@/lib/utils/cn";
import styles from "./code.module.css";

export type CodeProps = ComponentPropsWithRef<"code">;

/** Inline code: an identifier, a key, a command. Sized relative to the text
 *  around it, so it fits any line it sits in. */
export function Code({ className, ...props }: CodeProps) {
  return <code {...props} className={cn(styles.root, className)} />;
}

components/typography/code/code.module.css

@layer primitive {
  .root {
    padding: 0.1em 0.35em;
    border: 1px solid var(--line);
    border-radius: var(--radius-1);
    background: var(--surface-sunk);
    color: var(--ink);
    font-family: var(--font-mono);
    font-size: 0.9em;
    overflow-wrap: anywhere;
  }
}

components/typography/kbd/doc.ts

/**
 * Kbd — keys to press.
 *
 * ┌───────────────────────────────────────────────────────────────────────────┐
 * │ § CONTRACT — the oracle. Names no library, contains no code.              │
 * └───────────────────────────────────────────────────────────────────────────┘
 *
 * # Shape
 *
 *     keys   one key, or a combination: ["⌘", "K"]
 *
 * # Behaviour
 *
 * R1  A combination is one kbd element holding a kbd per key, as HTML nests
 *     them; each key is read out.
 * R2  It scales with the text around it.
 */
export {};

components/typography/kbd/kbd.tsx

import { cn } from "@/lib/utils/cn";
import styles from "./kbd.module.css";

export type KbdProps = {
  /** One key, or a combination pressed together: ["⌘", "K"]. */
  keys: string | readonly string[];
  className?: string;
};

/** Keys to press. A combination is one <kbd> of <kbd>s, as HTML nests
 *  them, and is read out key by key. */
export function Kbd({ keys, className }: KbdProps) {
  const list = typeof keys === "string" ? [keys] : keys;
  return (
    <kbd className={cn(styles.root, className)}>
      {list.map((key, index) => (
        <kbd key={`${index}-${key}`} className={styles.key}>
          {key}
        </kbd>
      ))}
    </kbd>
  );
}

components/typography/kbd/kbd.module.css

@layer primitive {
  .root {
    display: inline-flex;
    align-items: center;
    gap: 2px;
    font-family: var(--font-sans);
    white-space: nowrap;
  }
  .key {
    display: inline-grid;
    min-width: 1.6em;
    height: 1.6em;
    place-items: center;
    padding: 0 0.35em;
    border: 1px solid var(--line-strong);
    border-bottom-width: 2px;
    border-radius: var(--radius-1);
    background: var(--surface-sunk);
    color: var(--ink-2);
    font: inherit;
    font-size: 0.8em;
    line-height: 1;
  }
}