/* ===========================================================================
   amd-challenge.css — sending a list to a friend, and the reveal
   (v2/shared/amd-challenge.js)

   Tokens only. Three surfaces, and each one is a decision already made
   somewhere else on this site rather than a new one:

     THE INVITATION   the sealed card a friend lands on. A navy band: --navy on
                      a cream page, --navy-lift on a dark one, because a dark
                      interface signals a band by LIFTING (amd-rules.css).
     THE REVEAL       a full-screen dark room, the same room Compare is on the
                      Big Board: --dk fading to --dk0, cream type, gold for
                      structure, orange only for the one action.
     THE SHEET        the send choice. Page surfaces (--panel, --ink), because
                      it sits over the page the sender is working on.

   Gold carries the match. It is structural on navy everywhere else on the
   site ("this is the record"), and a shared answer is the record two people
   now have in common.
   ========================================================================= */

/* ── THE INVITATION ────────────────────────────────────────────────────── */
.chx-invite{--chx-band:var(--navy);position:relative;overflow:hidden;
  margin:0 0 var(--s5);padding:var(--s5);border-radius:var(--r-lg);
  background:radial-gradient(520px 260px at 92% -20%,color-mix(in srgb,var(--navy-lift) 80%,transparent),transparent 70%),var(--chx-band);
  color:var(--on-dk)}
body.dark .chx-invite,html.amd-dark body .chx-invite,html[data-amd-surface="dark"] body .chx-invite{--chx-band:var(--navy-lift)}
.chx-eyebrow{font-size:var(--t-tiny);font-weight:var(--w-bold);letter-spacing:var(--track-caps);text-transform:uppercase;color:var(--gold-lt)}
.chx-invite-h{margin:var(--s2) 0 0;font-family:var(--font-display);font-weight:var(--w-bold);font-size:var(--t-h2);
  line-height:1.02;letter-spacing:var(--track-display);color:var(--on-dk);text-wrap:balance}
/* N places, face down, five to a row — a Top 10 is two even rows that fill
   the card's width at 390px instead of three ragged ones. */
.chx-seals{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:var(--s2);margin:var(--s4) 0 0;padding:0;list-style:none}
.chx-seals.chx-c1{grid-template-columns:minmax(0,1fr)}
.chx-seals.chx-c2{grid-template-columns:repeat(2,minmax(0,1fr))}
.chx-seals.chx-c3{grid-template-columns:repeat(3,minmax(0,1fr))}
.chx-seals.chx-c4{grid-template-columns:repeat(4,minmax(0,1fr))}
.chx-seal{display:flex;align-items:center;justify-content:space-between;gap:var(--s1);height:calc(var(--s6) + var(--s1));padding:0 var(--s3);
  border-radius:var(--r-sm);background:color-mix(in srgb,var(--dk) 55%,transparent);
  border:1px solid color-mix(in srgb,var(--gold-lt) 34%,transparent)}
.chx-seal b{font-family:var(--font-display);font-size:var(--t-base);line-height:1;color:var(--gold-lt);font-variant-numeric:tabular-nums}
.chx-seal svg{flex:none;width:12px;height:12px;fill:var(--on-dk-soft);stroke:var(--on-dk-soft);stroke-width:1.6}
.chx-shown{margin:var(--s4) 0 0;padding:0;list-style:none;display:grid;gap:var(--s1);counter-reset:chx}
.chx-shown li{display:flex;align-items:baseline;gap:var(--s3);font-size:var(--t-base);color:var(--on-dk)}
.chx-shown li b{font-family:var(--font-display);color:var(--gold-lt);min-width:2ch;text-align:right;font-variant-numeric:tabular-nums}
.chx-invite-meta{margin-top:var(--s4);font-size:var(--t-tiny);color:var(--on-dk-soft);letter-spacing:var(--track-caps);text-transform:uppercase}

/* After the reveal the invitation becomes the record of it. */
.chx-done{display:flex;flex-wrap:wrap;align-items:flex-end;gap:var(--s3) var(--s5);margin-top:var(--s4)}
.chx-done-n{font-family:var(--font-display);font-size:var(--t-h1);line-height:.9;color:var(--gold-lt);font-variant-numeric:tabular-nums}
.chx-done-n small{font-size:var(--t-h3);color:var(--on-dk-soft)}
.chx-done-t{font-size:var(--t-small);line-height:1.5;color:var(--on-dk-soft);padding-bottom:var(--s1)}
.chx-acts{display:flex;flex-wrap:wrap;gap:var(--s2);margin-top:var(--s4)}

/* ── BUTTONS, ON NAVY ──────────────────────────────────────────────────────
   One orange button per screen (the rulebook), so the quiet one is an
   outline in the room's own cream. */
.chx-btn{display:inline-flex;align-items:center;justify-content:center;gap:var(--s2);min-height:var(--tap);
  padding:0 var(--s5);border-radius:var(--r-sm);border:1px solid transparent;font:inherit;
  font-size:var(--t-small);font-weight:var(--w-bold);cursor:pointer;text-decoration:none}
/* [hidden] does its work through the user-agent sheet, and display:inline-flex
   above beats it — the CLAUDE.md "hidden is the weakest thing in CSS" entry.
   The send sheet hides Cancel once a link exists, so it has to mean it. */
.chx-btn[hidden]{display:none}
.chx-btn svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.chx-btn-go{background:var(--accent-cta);color:var(--on-cta);box-shadow:var(--lift-cta)}
.chx-btn-quiet{background:none;color:var(--on-dk);border-color:color-mix(in srgb,var(--on-dk) 28%,transparent)}
.chx-btn:focus-visible{outline:2px solid var(--gold-lt);outline-offset:2px}
@media (hover:hover) and (pointer:fine){
  .chx-btn-quiet:hover{border-color:var(--gold-lt);color:var(--gold-lt)}
}

/* ── THE REVEAL ────────────────────────────────────────────────────────── */
.chx-room{position:fixed;inset:0;z-index:400;display:flex;flex-direction:column;color:var(--on-dk);
  background:radial-gradient(900px 520px at 78% -12%,color-mix(in srgb,var(--navy-lift) 70%,transparent),transparent 65%),
             linear-gradient(180deg,var(--dk),var(--dk0));
  opacity:0;transition:opacity var(--dur-slow) var(--ease);font-family:var(--font-text)}
.chx-room.is-in{opacity:1}
.chx-room-in{flex:1;min-height:0;width:100%;max-width:640px;margin:0 auto;display:flex;flex-direction:column;
  padding:var(--s4) var(--s4) 0;box-sizing:border-box}
.chx-body{flex:1;min-height:0;display:flex;flex-direction:column}
.chx-main{flex:1;min-height:0;display:flex;flex-direction:column}

.chx-top{display:flex;align-items:center;gap:var(--s3)}
.chx-top .chx-eyebrow{flex:1;min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chx-x{flex:none;display:grid;place-items:center;width:var(--tap);height:var(--tap);margin-right:calc(-1 * var(--s2));
  border:none;border-radius:var(--r-pill);background:none;color:var(--on-dk-soft);cursor:pointer}
.chx-x svg{width:20px;height:20px;stroke:currentColor;stroke-width:1.8;fill:none;stroke-linecap:round}
.chx-x:focus-visible{outline:2px solid var(--gold-lt);outline-offset:0}

.chx-score{display:flex;align-items:flex-end;gap:var(--s3);margin-top:var(--s2)}
.chx-n{font-family:var(--font-display);font-weight:var(--w-bold);font-size:var(--t-h1);line-height:.86;
  color:var(--gold-lt);font-variant-numeric:tabular-nums;letter-spacing:var(--track-display)}
.chx-n small{font-size:var(--t-h3);color:var(--on-dk-soft);letter-spacing:0}
.chx-n b{display:inline-block;transition:transform var(--dur-base) var(--ease)}
.chx-n b.is-bump{transform:translateY(calc(-1 * var(--s1)))}
.chx-score-l{padding-bottom:var(--s1);font-size:var(--t-small);line-height:1.35;color:var(--on-dk-soft)}
.chx-score-l b{display:block;font-family:var(--font-display);font-size:var(--t-lead);color:var(--on-dk)}
.chx-status{min-height:1.5em;margin-top:var(--s2);font-size:var(--t-tiny);letter-spacing:var(--track-caps);text-transform:uppercase;color:var(--on-dk-soft)}

.chx-heads,.chx-row{display:grid;grid-template-columns:minmax(0,1fr) var(--s8) minmax(0,1fr);align-items:center;gap:var(--s2)}
.chx-heads{margin-top:var(--s3);padding:0 0 var(--s2);border-bottom:1px solid color-mix(in srgb,var(--on-dk) 14%,transparent);
  font-size:var(--t-tiny);font-weight:var(--w-bold);letter-spacing:var(--track-caps);text-transform:uppercase;color:var(--on-dk-soft)}
.chx-heads span{min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chx-heads span:last-child{text-align:left}
.chx-rows{flex:1;min-height:0;overflow-y:auto;margin:0;padding:var(--s2) 0 var(--s4);list-style:none;
  display:flex;flex-direction:column;gap:var(--s2);overscroll-behavior:contain}
.chx-row{min-height:calc(var(--tap) + var(--s2))}
.chx-rk{text-align:center;font-family:var(--font-display);font-size:var(--t-lead);color:var(--on-dk-soft);font-variant-numeric:tabular-nums;
  transition:color var(--dur-base) var(--ease)}
.chx-cell{min-width:0;height:100%;perspective:600px}
.chx-face{box-sizing:border-box;height:100%;min-height:calc(var(--tap) + var(--s2));display:flex;flex-direction:column;justify-content:center;
  gap:2px;padding:var(--s2) var(--s3);border-radius:var(--r-md);border:1px solid color-mix(in srgb,var(--on-dk) 12%,transparent);
  background:color-mix(in srgb,var(--dk2) 92%,transparent);transition:border-color var(--dur-base) var(--ease),background-color var(--dur-base) var(--ease)}
.chx-nm{font-size:var(--t-small);font-weight:var(--w-bold);color:var(--on-dk);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chx-cap{font-size:var(--t-tiny);color:var(--on-dk-soft);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chx-empty .chx-nm{font-weight:var(--w-normal);color:var(--on-dk-soft)}

/* Their side is a split-flap: the sealed back faces you, and turning over is
   the reveal. Both faces share one grid cell so the row never changes size. */
.chx-flip{display:grid;height:100%;transform-style:preserve-3d;transition:transform var(--dur-slow) var(--ease-sheet)}
.chx-flip>.chx-face{grid-area:1/1;backface-visibility:hidden;-webkit-backface-visibility:hidden}
.chx-face.chx-back{flex-direction:row;align-items:center;gap:var(--s3);
  border-color:color-mix(in srgb,var(--gold-lt) 30%,transparent)}
.chx-back i{flex:1;height:var(--s2);border-radius:var(--r-pill);background:color-mix(in srgb,var(--on-dk) 12%,transparent)}
.chx-back svg{flex:none;width:12px;height:12px;fill:var(--on-dk-soft);stroke:var(--on-dk-soft);stroke-width:1.6}
.chx-front{transform:rotateX(180deg)}
.chx-row.is-open .chx-flip{transform:rotateX(-180deg)}
.chx-row.is-same .chx-face{border-color:var(--gold-lt);background:color-mix(in srgb,var(--gold-lt) 10%,var(--dk2))}
.chx-row.is-same .chx-rk{color:var(--gold-lt)}

.chx-end{padding:var(--s4) 0 calc(var(--s4) + env(safe-area-inset-bottom));border-top:1px solid color-mix(in srgb,var(--on-dk) 14%,transparent);
  opacity:0;transform:translateY(var(--s2));transition:opacity var(--dur-slow) var(--ease),transform var(--dur-slow) var(--ease)}
.chx-end.is-in{opacity:1;transform:none}
.chx-end[hidden]{display:none}
.chx-facts{margin:0;padding:0;list-style:none;display:grid;gap:var(--s1);font-size:var(--t-small);line-height:1.45;color:var(--on-dk-soft)}
.chx-facts b{color:var(--on-dk);font-weight:var(--w-bold)}
.chx-skipbar{display:flex;justify-content:center;padding:var(--s3) 0 calc(var(--s3) + env(safe-area-inset-bottom))}
.chx-skipbar[hidden]{display:none}

/* ── THE SHEET ─────────────────────────────────────────────────────────── */
.chx-scrim{position:fixed;inset:0;z-index:390;display:flex;align-items:flex-end;justify-content:center;
  background:color-mix(in srgb,var(--dk0) 55%,transparent);opacity:0;transition:opacity var(--dur-base) var(--ease)}
.chx-scrim.is-in{opacity:1}
.chx-sheet{width:100%;max-width:520px;box-sizing:border-box;padding:var(--s5) var(--s5) calc(var(--s5) + env(safe-area-inset-bottom));
  background:var(--panel);color:var(--ink);border-radius:var(--r-lg) var(--r-lg) 0 0;box-shadow:var(--shadow-xl);
  transform:translateY(var(--s6));transition:transform var(--dur-slow) var(--ease-sheet)}
.chx-scrim.is-in .chx-sheet{transform:none}
@media (min-width:721px){.chx-scrim{align-items:center}.chx-sheet{border-radius:var(--r-lg)}}
.chx-sheet-k{font-size:var(--t-tiny);font-weight:var(--w-bold);letter-spacing:var(--track-caps);text-transform:uppercase;color:var(--muted)}
.chx-sheet-h{margin:var(--s1) 0 var(--s4);font-family:var(--font-display);font-weight:var(--w-bold);font-size:var(--t-h3);line-height:1.15;color:var(--ink)}
.chx-opts{display:grid;gap:var(--s2)}
.chx-opt{display:grid;grid-template-columns:1fr auto;align-items:center;gap:var(--s1) var(--s3);width:100%;padding:var(--s3) var(--s4);
  border:1px solid var(--line);border-radius:var(--r-md);background:var(--panel);font:inherit;text-align:left;color:var(--ink);cursor:pointer}
.chx-opt b{font-size:var(--t-base);font-weight:var(--w-bold)}
.chx-opt span{grid-column:1;font-size:var(--t-small);line-height:1.45;color:var(--soft)}
.chx-opt i{grid-column:2;grid-row:1/3;width:20px;height:20px;border-radius:50%;border:1px solid var(--line);box-sizing:border-box}
.chx-opt[aria-checked="true"]{border-color:var(--ink);background:var(--panel2)}
.chx-opt[aria-checked="true"] i{border:6px solid var(--ink)}
.chx-opt:focus-visible{outline:2px solid var(--ring-focus);outline-offset:2px}
.chx-sheet-note{margin:var(--s4) 0 0;font-size:var(--t-small);line-height:1.5;color:var(--soft)}
.chx-sheet-acts{display:flex;flex-wrap:wrap;gap:var(--s2);margin-top:var(--s4)}
.chx-sheet-acts .chx-btn-go{flex:1 1 auto}
.chx-btn-plain{background:none;color:var(--ink);border-color:var(--line)}
.chx-btn-plain:focus-visible{outline-color:var(--ring-focus)}
.chx-link{display:flex;gap:var(--s2);margin-top:var(--s4)}
.chx-link[hidden]{display:none}
.chx-link input{flex:1;min-width:0;min-height:var(--tap);padding:0 var(--s3);border:1px solid var(--line);border-radius:var(--r-sm);
  background:var(--tint);color:var(--ink);font:inherit;font-size:var(--t-small)}
.chx-sheet-msg{margin:var(--s3) 0 0;font-size:var(--t-small);color:var(--good-ink)}
.chx-sheet-msg[hidden]{display:none}
.chx-sheet-msg.is-bad{color:var(--bad-ink)}

/* ── ANSWERS, FOR THE PERSON WHO SENT IT ───────────────────────────────── */
.chx-answers{margin:0 0 var(--s5);border:1px solid var(--line);border-radius:var(--r-lg);background:var(--panel);overflow:hidden}
.chx-answers-h{display:flex;align-items:baseline;gap:var(--s2);padding:var(--s3) var(--s4);border-bottom:1px solid var(--line);
  font-size:var(--t-tiny);font-weight:var(--w-bold);letter-spacing:var(--track-caps);text-transform:uppercase;color:var(--muted)}
.chx-answers-h b{color:var(--ink);font-family:var(--font-display);font-size:var(--t-small);font-variant-numeric:tabular-nums}
.chx-answers ul{margin:0;padding:0;list-style:none}
.chx-ans{display:grid;grid-template-columns:minmax(0,1fr) auto auto;align-items:center;gap:var(--s3);width:100%;min-height:calc(var(--tap) + var(--s2));
  padding:var(--s2) var(--s4);border:none;border-top:1px solid var(--line);background:none;font:inherit;color:var(--ink);text-align:left;cursor:pointer}
.chx-answers li:first-child .chx-ans{border-top:none}
.chx-ans-who{min-width:0;display:flex;flex-direction:column;gap:2px}
.chx-ans-who b{font-size:var(--t-base);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chx-ans-who>span{font-size:var(--t-tiny);color:var(--muted)}
.chx-ans-n{font-family:var(--font-display);font-size:var(--t-lead);font-variant-numeric:tabular-nums;color:var(--ink)}
.chx-ans-n small{font-family:var(--font-text);font-size:var(--t-tiny);color:var(--muted)}
.chx-ans svg{width:16px;height:16px;fill:none;stroke:var(--muted);stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.chx-new{display:inline-block;margin-left:var(--s2);padding:0 var(--s2);border-radius:var(--r-pill);background:var(--accent-wash);
  font-size:var(--t-micro);font-weight:var(--w-bold);letter-spacing:var(--track-caps);text-transform:uppercase;color:var(--accent-ink);vertical-align:middle}
.chx-ans:focus-visible{outline:2px solid var(--ring-focus);outline-offset:-2px}
@media (hover:hover) and (pointer:fine){.chx-ans:hover{background:var(--tint)}}
.chx-pill{display:inline-block;padding:0 var(--s2);border-radius:var(--r-pill);background:var(--accent-wash);
  font-size:var(--t-micro);font-weight:var(--w-bold);letter-spacing:var(--track-caps);text-transform:uppercase;color:var(--accent-ink);white-space:nowrap}

/* ── WIDE SCREENS ─────────────────────────────────────────────────────────
   Last, so it can override the base rules above it: a media query carries no
   extra specificity, and an override placed above its target loses. */
/* A wide screen puts the score and the end BESIDE the rows. Stacked at 1440
   the tenth row fell under the fold the moment the facts arrived, on a
   screen with a thousand pixels of navy either side of it. */
@media (min-width:900px){
  .chx-room-in{max-width:1040px;padding:var(--s6) var(--s6) 0}
  .chx-body{display:grid;grid-template-columns:minmax(0,1fr) 320px;grid-template-rows:auto 1fr;
    grid-template-areas:"main a" "main b";column-gap:var(--s8);padding-bottom:var(--s6)}
  .chx-side-a{grid-area:a;padding-top:var(--s3)}
  .chx-side-b{grid-area:b;align-self:start}
  .chx-main{grid-area:main}
  .chx-end{border-top:none;padding-top:var(--s5)}
  .chx-skipbar{justify-content:flex-start}
  .chx-n{font-size:calc(var(--t-h1) * 1.5)}
  .chx-score{flex-direction:column;align-items:flex-start;gap:var(--s1)}
}

/* ── REDUCED MOTION ────────────────────────────────────────────────────────
   The movement goes; the acknowledgement stays (the rulebook's rule for the
   feel layer). The JS also skips the countdown and opens every row at once,
   so a reader who asked for less motion gets the answer, not a slideshow. */
@media (prefers-reduced-motion:reduce){
  .chx-room,.chx-end,.chx-scrim,.chx-sheet,.chx-flip,.chx-n b{transition:none}
  .chx-flip>.chx-face{backface-visibility:visible;-webkit-backface-visibility:visible}
  .chx-front{transform:none}
  .chx-row .chx-front{visibility:hidden}
  .chx-row.is-open .chx-flip{transform:none}
  .chx-row.is-open .chx-back{visibility:hidden}
  .chx-row.is-open .chx-front{visibility:visible}
}

/* Read aloud, never drawn: the result, said once when the room finishes. */
.chx-sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}

/* The score, then the facts under it, on the invitation once it is done. */
.chx-done-facts{margin-top:var(--s3)}