.musicBarQueue never actually had a position set on desktop despite its
own comment saying it should float above the bar - toggling it visible
just pushed the real controls out of the way instead, growing the
fixed bottom bar upward. Mobile had position: relative with a high
z-index to at least show above the full-screen now-playing panel, but
that left it sized/placed by normal flow, overlapping the very toggle
button used to open it with no other way to close it.
Now: musicBar gets position: relative, desktop musicBarQueue floats
via position: absolute; bottom: 100% without touching the bar's own
layout, and mobile gets a proper position: fixed; inset: 0 overlay.
Also added a dedicated close button plus a click-outside-closes
listener, so closing it never again depends on where the toggle button
happens to render underneath.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>