╭─ FFT ─╮
│ ▲ ● ▼ │
╰───────╯

Here we go — two more forms for your little field‑marker.

Dark‑mode “inverse” version#

Conceptually, dark‑mode here just means: designed to sit on a dark background and feel like a lit glyph.

You can treat this as the intended dark‑mode version:

╭────────╮
│  FFT   │
│  ▲ ● ▼ │
╰────────╯

Usage notes:

• On dark backgrounds, render the box + text in light gray or white.
• On light backgrounds, you can drop the fill and keep it as line art.

If you ever move this into SVG, you’d literally invert: dark fill, light strokes.

Monospace‑tightened version#

This one is ASCII‑only, terminal‑safe, and compact:

+--FFT--+
| ^ o v |
+-------+

Or even tighter:

+ FFT +
|^ o v|
+-----+

• ^ o v keeps the triadic up/mid/down motion.
• All characters are plain ASCII, so it survives logs, terminals, and code comments.