The activity declares no `screenOrientation` and handles `orientation` and
`screenSize` itself, so turning the phone over is a resize and nothing else —
the audio thread, the stack and the screen's scroll all survive it, and the
layout is the only thing that has to answer. Two media queries do that. The
player sheet is the one surface whose portrait shape cannot survive a wide
viewport: its artwork is a square sized by WIDTH, so at 915×411 the cover came
out 879px tall and the title, the lane, the transport and the face buttons sat
below the bottom of a sheet that does not scroll — a corner of the cover and no
way to pause. Sideways it is two columns: the head across the top, the cover
down the left sized by HEIGHT, and the track, the scrubber, the transport and
the faces stacked on the right. With lyrics or the queue up, the face takes the
cover's column and the thumbnail goes — the record is already the ground behind
the whole sheet. That is an aspect problem rather than a height one, so the rule
keys off `orientation: landscape` alone and a tablet gets the same two columns.

The rest is a phone-sized query (`max-height: 560px`). The nav comes down to
Android's own 48dp minimum and the mini bar to a 60dp row over the same lane
strip, which gives the page back 22 of a 411-pixel screen — the chrome was 46%
of the height, it is 40%. The artist hero stops being a 300px portrait, which
covered its own Play button with the mini bar, and becomes a 190px banner: what
the desktop's hero has always been. The record head puts the cover beside the
title rather than above it, again the desktop's own shape, so Play is in view
without a scroll. A half sheet may take all but 36px of the height instead of
76% of it. Everything else — the grids, the rails, the artwork viewer, the
tap-to-sync room, the chat composer — already answered to width and was left
alone. `viewport-fit=cover` means the cutout and the gesture pill come in from
the SIDES in landscape, so the shell reads `--inset-left` / `--inset-right`
beside the top and bottom ones now. Those rules are appended at the end of
`shell.css` on purpose: they have to come after `.gbar`'s padding, `.mini`'s
and `.toast`'s left/right to win at equal specificity.