Metering
Analogue VU and PPM needles, LED bargraphs, arc loudness meters, vacuum-fluorescent displays and an EQ with RTA and spectrogram overlay. Every meter is driven by --value / --peak; the gentle movement here is CSS keyframes (.is-demo-live) and stops under reduced motion.
Analogue VU .vu
Labelled arc scale from list markup, red zone from 0 VU, peak LED, a needle with 300 ms VU ballistics. Cream paper face in light themes, the theme's own face in dark ones.
.is-pair.is-backlit.is-themed.is-vfd.is-amber.is-ppmLED bargraph .ledbar
Dual column with a centre scale, a red reference band, ghosted unlit segments, peak hold and an overs cap.
Horizontal bargraph .is-horizontal
The same contract laid across, with a shared scale under it. Right has tripped its overs cap.
Arc loudness meters .ledarc
Segmented arcs with dB above and % modulation below. The keys are radios: meter mode redraws both meters, Reset clears the peak and the overs, all with :has().
VFD panel .vfd
A receiver window: phosphor level bars, a frequency readout over its ghosted 8-segments, a nine-band spectrum, and dim annunciators.
EQ with RTA and spectrogram .eq-graph
Spectrogram at the back (from the pre or post signal), then the pre and post 31-band RTA at 75% with peak-hold caps, then the EQ curve, its bands and numbered handles, always on top. Pick the RTA source, range, decay and detector, and the spectrogram's colour scale; every control is a radio or checkbox.