[Bug]: Large text is impossible in T3 Code #32790

Problem

It is impossible to get large text in T3 Code.

1. Chat messages don't render at the set size

Both user and assistant messages are rendered by ChatMarkdown with text-sm (0.875rem, apps/web/src/components/ChatMarkdown.tsx). The main text in the app is always 87.5% of the size you set:

2. The maximum is 20px and there's no workaround

All font size settings top out at 20px (18px for Code). In the desktop app, Cmd + does nothing. In the web app, the browser's zoom enlarges the page, but it scales the whole UI too.

3. Interface font size scales the whole UI, not the text

The setting sets the root font size (apps/web/src/appearanceFonts.ts). Spacing (--spacing: 0.25rem) and corner rounding (--radius: 0.5rem) are in rem, so padding, margins, gaps, widths and rounded corners all grow with it.

This defeats the point of a font size setting:

• Bigger text needs more room, and the scaled spacing takes it away. Wider sidebars, padding and gaps leave less space for content, so less fits on screen just when the text needs more space.
• It's the same as zooming. If a font size setting scales everything, it does nothing that zooming doesn't already do. A font size setting exists to make text bigger while the layout stays the same.
• Text and spacing need different sizes. Someone who needs 24px text doesn't need 24px-scale padding. Spacing should stay fixed so the extra room goes to the text.

Recommendation: define Tailwind's spacing unit in pixels so spacing no longer follows the root font size:

@theme {
  --spacing: 4px;
}

Expected

• Chat messages render at the configured size: 16px means 16px.
• Font sizes can go above 20px. Maybe to 32px or without a limit.
• Font size settings change the size of text, not spacing or layout.

Prior requests

• [Bug/Feature]: Composer text stays tiny at max font size; allow 20px+ input text #19882 asked for "20px+ input text". It was closed after the reply that the setting "goes up to 20px".
• [Feature]: Chat text size setting, separate from Interface font size #16862 said "It would also help if it went above 20px". It was closed as a duplicate of [Feature]: Independently configurable font size for AI responses #10769.