The card-deck tape stops underlapping the next card on mobile

On mobile the Card deck options tape slid under the cards below it.

.pstocks hangs at top:100%, i.e. below its own card and over the next one.
Every .card is position:relative with NO z-index, so they all sit at the
same stacking level and later cards paint over earlier ones in document
order. The tape's own z-index:2 only orders it WITHIN its card, which is
why it looked correct on the last card of a row and vanished under the
next card everywhere else. On a phone the grid is one column, so the very
next card is directly beneath -- hence "really bad on mobile" rather than
merely wrong.

Raising the CARD while one of its tapes is open lifts the whole stacking
context above its siblings. z-index 5 sits above any card and below the
sticky section header at 6, so a revealed tape never covers the header the
reader scrolls with -- a menu that hides its own navigation would be a
worse bug than this one. The tape also gains a stronger shadow so it reads
as sitting ON the card below rather than tangled with it; without an
opaque, shadowed surface the next card's text shows through, which is the
other half of what "underlapping" looks like.

Covers both tapes -- the card sizes and the new packet variants -- since
they share the disclosure.

library/components/poster/PosterWall.vue

@@ -794,6 +794,15 @@ useShadowStyles(
   'display:flex;flex-wrap:wrap;gap:3px;justify-content:center;' +
   'box-shadow:0 1px 4px rgba(0,0,0,.10);cursor:default}' +
   '.is-dark .pstocks{background:#132019;border-color:rgba(110,231,183,.24)}' +
+  // ★ The open card outranks its siblings. 5 sits above any card (all of which are z-index:auto)
+  // and below the sticky section header at 6, so a revealed tape never covers the header the
+  // reader uses to scroll — a menu that hides its own navigation is a worse bug than the one
+  // being fixed here.
+  '.card.has-tape-open{z-index:5}' +
+  // The tape is OPAQUE and casts a shadow so it reads as sitting ON the card below rather than
+  // being tangled with it. Without a solid background the next card's text shows through, which is
+  // the other half of what "underlapping" looks like on a phone.
+  '.pstocks{box-shadow:0 2px 10px rgba(0,0,0,.18)}' +
   '.pfs > legend{margin:0 auto;padding:0 5px;font-size:8px;text-transform:uppercase;' +
   'letter-spacing:.6px;font-weight:700;color:#8a93a0}' +
   '.is-dark .pfs > legend{color:#7f9c8c}' +
@@ -1048,8 +1057,19 @@ useShadowStyles(
         </select>
       </div>
       <div v-show="!isCollapsed(sec.name)" class="grid" :style="gridStyle">
+        <!-- ★ 'has-tape-open' RAISES THE WHOLE CARD while one of its tapes is revealed. Driver
+             2026-09-28 on mobile: the Card deck options tape "is underlapping everything … really
+             bad on mobile". Cause: .pstocks hangs at top:100%, i.e. BELOW its own card and over the
+             next one, but every .card is position:relative with NO z-index — so they all sit at the
+             same stacking level and LATER cards paint over earlier ones in document order. The
+             tape's own z-index:2 only orders it WITHIN its card, which is why it looked fine on the
+             last card of a row and disappeared under the next one everywhere else. It is worse on a
+             phone because the grid is one column, so the very next card is directly beneath.
+             Raising the CARD lifts its whole stacking context above its siblings. -->
         <div v-for="item in sec.items" :key="item.id" class="card"
-          :class="{ 'is-last': lastShown === item.id }" :data-list-id="item.id">
+          :class="{ 'is-last': lastShown === item.id,
+                    'has-tape-open': deckOpenFor === deckKey(item.id, 'deck') || deckOpenFor === deckKey(item.id, 'packet') }"
+          :data-list-id="item.id">
 
           <!-- A TOGGLE (showOnMap clears the selection on a second press), so it says whether it is on:
                without aria-pressed a second press sounded identical to the first to a screen reader. -->