/* Full-viewport fixed backdrop. Sits behind the detail content (.mix-detail-foreground is z-index:1)
   and never intercepts pointer events — except the zoom slider, which re-enables them on itself.

   Footer clip (Phase 10 W1, spec §2c): the backdrop must stop cleanly ABOVE the audio player bar so
   no lava/waveform pixel paints over or under it. `overflow: hidden` clips the canvas to this box, and
   `bottom` is inset by `--player-height`, which AudioPlayerBar publishes on :root via its ResizeObserver
   (Interop/layout/spacer.ts). The observer now points at whichever element is live:
     expanded  → the full player dock (tracks breakpoint reflow + error-banner growth)
     minimized → the minimized-dock FAB container (~56–60 px)
   so --player-height is always non-zero while the player is mounted and the clip line follows the bar in
   BOTH states (fix §1 / p10-reframe-w1-fix). The 0px fallback keeps the backdrop full-height on any
   page that does not host the player. */
.mix-waveform-bg {
    position: fixed;
    inset: 0;
    bottom: var(--player-height, 0px);
    z-index: 0;
    pointer-events: none;
    overflow: hidden;
}

/* Fill / container-sizing mode (Phase 12 §6c, mode C). The contained hosts (the NowPlaying card)
   set Fill="true": the canvas fills its nearest positioned ancestor instead of the viewport, and the
   footer clip drops (there is no player bar to clear — the bounding box IS the clip). The host is
   responsible for giving this layer a positioned, sized parent. `inset: 0` over `position: absolute`
   makes the box exactly that parent's content box; `overflow: hidden` still clips the canvas to it.
   The canvas backing-store sizing in WaveformVisualizer.ts is unchanged — it already measures the
   canvas's own box, so this purely re-parents the box from the viewport to the container. */
.mix-waveform-bg--fill {
    position: absolute;
    inset: 0;
    z-index: 0;
}

/* The canvas fills the viewport. All ribbon shading (luminous depth, soft edges) is drawn inside the
   canvas by the WebGL2 fragment shader. NO CSS backdrop-filter: it was a confirmed per-frame perf killer
   on the Canvas predecessor and is exactly the cost the GPU move exists to eliminate (spec §2, §5.2);
   the glass treatment returns in-shader in Wave 3. */
.mix-waveform-canvas {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    display: block;
}