/* The examples (/examples/): the gallery, and each example's lab: the stage (a face, a scene) on the left with its
   subtitles and pop-ups, and a panel on the right with tabs (Talk, Look, Code). One column on a phone. */

/* --- the gallery ------------------------------------------------------------------------------------------------ */
.ex-hero { position: relative; padding: 64px 0 28px; overflow: hidden; }
.ex-hero::before { content: ""; position: absolute; inset: -40% -10% auto; height: 520px; pointer-events: none;
  background: radial-gradient(50% 60% at 30% 40%, rgba(34, 211, 238, .14), transparent 70%),
    radial-gradient(40% 50% at 75% 30%, rgba(167, 139, 250, .14), transparent 70%); }
.ex-hero .wrap { position: relative; }
.ex-hero h1 { max-width: 16ch; }
.ex-hero .lede { max-width: 62ch; }
.ex-stats { display: flex; flex-wrap: wrap; gap: 10px 26px; margin: 1.6rem 0 0; padding: 0; list-style: none; color: var(--muted); font-size: 0.95rem; }
.ex-stats b { display: block; font: 600 1.5rem/1.1 var(--display); color: var(--text); }

.ex-filters { display: flex; flex-wrap: wrap; gap: 8px; margin: 30px 0 18px; }
.ex-filters button { border: 1px solid var(--line-2); background: rgba(13, 22, 48, .55); color: var(--muted); border-radius: 999px;
  padding: 8px 16px; font: 500 0.9rem var(--body); cursor: pointer; }
.ex-filters button:hover { color: var(--text); border-color: rgba(34, 211, 238, .5); }
.ex-filters button[aria-pressed="true"] { color: #050914; background: var(--grad); border-color: transparent; }

.ex-section { padding: 10px 0 64px; }
.ex-section h2 { margin: 0 0 0.4rem; font-size: clamp(1.5rem, 2.6vw, 2rem); max-width: none; }
.ex-section > .wrap > .lede.small { margin-bottom: 1.4rem; max-width: 70ch; }
.ex-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); gap: 18px; }
.ex-card { position: relative; display: grid; grid-template-rows: auto 1fr; border-radius: 18px; overflow: hidden; text-decoration: none;
  border: 1px solid var(--line); background: rgba(13, 22, 48, .6); transition: transform .2s ease, border-color .2s ease, box-shadow .2s ease; }
.ex-card:hover { transform: translateY(-3px); border-color: rgba(34, 211, 238, .45); box-shadow: 0 24px 50px -30px rgba(34, 211, 238, .55); }
.ex-card[hidden] { display: none; }
.ex-shot { position: relative; aspect-ratio: 16 / 10; overflow: hidden; background: var(--night-2); }
.ex-shot img { display: block; width: 100%; height: 100%; object-fit: cover; transition: transform .5s ease; }
.ex-card:hover .ex-shot img { transform: scale(1.04); }
.ex-shot .ex-kind { position: absolute; top: 10px; left: 10px; }
.ex-kind { display: inline-block; padding: 4px 8px; border-radius: 7px; font: 500 0.68rem/1 var(--mono); letter-spacing: .12em;
  text-transform: uppercase; color: var(--cyan); background: rgba(6, 11, 24, .82); border: 1px solid rgba(34, 211, 238, .35); }
.ex-kind.k2d { color: #f0b89a; border-color: rgba(240, 184, 154, .4); }
.ex-kind.three { color: #c4b5fd; border-color: rgba(196, 181, 253, .4); }
.ex-kind.use { color: #86efac; border-color: rgba(134, 239, 172, .4); }
.ex-body { display: grid; align-content: start; gap: 8px; padding: 16px 18px 18px; }
.ex-body h3 { margin: 0; font-size: 1.12rem; }
.ex-body p { color: var(--muted); font-size: 0.93rem; line-height: 1.5; }
.ex-tags { display: flex; flex-wrap: wrap; gap: 6px; margin: 4px 0 0; padding: 0; list-style: none; }
.ex-tags li { padding: 3px 9px; border-radius: 999px; font-size: 0.76rem; color: var(--muted); border: 1px solid var(--line-2); }
.ex-tags li.voice { color: #fde68a; border-color: rgba(253, 230, 138, .35); }
.ex-tags li.voice::before { content: ""; display: inline-block; width: 6px; height: 6px; margin-right: 6px; border-radius: 50%;
  background: #fde68a; vertical-align: 1px; box-shadow: 0 0 6px #fde68a; }
.ex-card.more .ex-shot { aspect-ratio: 16 / 7; }
.ex-cta { margin-top: 10px; }

/* --- an example ------------------------------------------------------------------------------------------------- */
.ex { padding: 30px 0 70px; }
.ex-crumbs { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 0 0 14px; color: var(--dim); font-size: 0.9rem; }
.ex-crumbs a { color: var(--muted); text-decoration: none; }
.ex-crumbs a:hover { color: var(--text); }
.ex-head { display: flex; flex-wrap: wrap; align-items: end; justify-content: space-between; gap: 12px 30px; margin-bottom: 22px; }
.ex-head h1 { font-size: clamp(2rem, 4vw, 3rem); }
.ex-head .lede.small { margin-top: 0.7rem; max-width: 66ch; }
.ex-head .ex-tags { margin: 0; }

.ex-lab { display: grid; grid-template-columns: minmax(0, 1.45fr) minmax(320px, 1fr); gap: 24px; align-items: start; }
.ex-stage { position: relative; height: min(76vh, 700px); min-height: 380px; border-radius: 22px; overflow: hidden;
  border: 1px solid var(--line); background: radial-gradient(70% 60% at 50% 42%, rgba(99, 102, 241, .16), transparent 70%), var(--night-2);
  position: sticky; top: 84px; }
.ex-stage > canvas, .ex-stage .ex-canvas { display: block; width: 100%; height: 100%; touch-action: none; }
.ex-stage.square { aspect-ratio: auto; }
.ex-loading { position: absolute; inset: 0; display: grid; place-items: center; color: var(--muted); font: 500 0.9rem var(--mono);
  letter-spacing: .08em; pointer-events: none; transition: opacity .4s; }
.ex-loading.done { opacity: 0; }
.ex-sub { position: absolute; left: 50%; bottom: 16px; transform: translateX(-50%); width: max-content; max-width: calc(100% - 32px);
  margin: 0; padding: 9px 14px; border-radius: 12px; background: rgba(10, 18, 38, .86); border: 1px solid var(--line-2);
  color: var(--text); font-size: 0.98rem; line-height: 1.45; text-align: center; pointer-events: none;
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); box-shadow: 0 14px 34px -18px rgba(0, 0, 0, .9); }
.ex-sub[hidden] { display: none; }
.ex-tip { position: absolute; top: 14px; right: 14px; margin: 0; padding: 6px 10px; border-radius: 10px; font-size: 0.8rem;
  color: var(--muted); background: rgba(10, 18, 38, .7); border: 1px solid var(--line); pointer-events: none; }
.ex-badge { position: absolute; top: 14px; left: 14px; display: flex; align-items: center; gap: 10px; margin: 0; padding: 7px 12px;
  border-radius: 12px; background: rgba(10, 18, 38, .78); border: 1px solid var(--line-2); font-size: 0.88rem; color: var(--text); }
.ex-badge img { width: 28px; height: 28px; border-radius: 50%; object-fit: cover; }
/* a card the character shows (a kiosk's info, a flashcard, a recipe) */
.ex-pop { position: absolute; top: 16px; right: 16px; width: min(300px, calc(100% - 32px)); margin: 0; padding: 14px 16px;
  border-radius: 16px; border: 1px solid rgba(34, 211, 238, .45); background: rgba(8, 14, 32, .9); color: var(--text);
  box-shadow: 0 24px 50px -24px rgba(34, 211, 238, .55); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
  transform-origin: top right; animation: ex-pop .35s cubic-bezier(.2, .9, .3, 1.3); }
.ex-pop[hidden] { display: none; }
.ex-pop h4 { margin: 0 0 6px; font: 600 1.05rem/1.25 var(--display); }
.ex-pop p { margin: 0; color: var(--muted); font-size: 0.92rem; line-height: 1.5; }
.ex-pop .big { font: 600 1.5rem/1.2 var(--display); color: var(--text); margin-bottom: 6px; }
.ex-pop .say { margin-top: 8px; font: 500 0.82rem var(--mono); color: var(--cyan); }
@keyframes ex-pop { from { opacity: 0; transform: scale(.85) translateY(-6px); } }
@media (prefers-reduced-motion: reduce) { .ex-pop { animation: none; } }

/* the panel */
.ex-panel { min-width: 0; }
.ex-tabs { display: flex; gap: 4px; margin: 0 0 16px; border-bottom: 1px solid var(--line); }
.ex-tabs [role=tab] { border: 0; background: none; color: var(--muted); font: 600 0.95rem var(--display); padding: 10px 14px;
  border-bottom: 2px solid transparent; margin-bottom: -1px; cursor: pointer; }
.ex-tabs [role=tab]:hover { color: var(--text); }
.ex-tabs [role=tab][aria-selected="true"] { color: var(--text); border-bottom-color: var(--cyan); }
.ex-pane[hidden] { display: none; }
.ex-h { margin: 20px 0 10px; font: 500 0.76rem/1.3 var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--dim); }
.ex-pane > .ex-h:first-child, .ex-pane > :first-child > .ex-h:first-child { margin-top: 2px; }
.ex-note, .ex-fine { margin: 8px 0 0; color: var(--dim); font-size: 0.86rem; line-height: 1.5; }
.ex-fine a, .ex-note a { color: var(--muted); }
.ex-label { margin: 14px 0 8px; color: var(--muted); font-size: 0.9rem; }
.ex-group:first-child .ex-label { margin-top: 0; }

.ex-slider { display: grid; grid-template-columns: 7.4rem minmax(0, 1fr) 3rem; align-items: center; gap: 12px; margin: 7px 0;
  color: var(--muted); font-size: 0.92rem; }
.ex-slider input { width: 100%; accent-color: var(--cyan); }
.ex-slider output { font: 500 0.8rem var(--mono); color: var(--text); text-align: right; }
.ex-row-ctl { display: grid; grid-template-columns: 7.4rem minmax(0, 1fr); align-items: center; gap: 12px; margin: 10px 0;
  color: var(--muted); font-size: 0.92rem; }
.ex-row-ctl select, .ex-row-ctl input[type="file"] { width: 100%; min-width: 0; padding: 8px 10px; border-radius: 10px;
  border: 1px solid var(--line-2); background: #070d1f; color: var(--text); font: 400 0.9rem var(--body); }
.ex-row-ctl input[type="color"] { width: 54px; height: 34px; padding: 2px; border-radius: 9px; border: 1px solid var(--line-2); background: #070d1f; }
.ex-toggle { display: inline-flex; align-items: center; gap: 10px; margin: 6px 18px 6px 0; color: var(--muted); font-size: 0.92rem; cursor: pointer; }
.ex-toggle input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.ex-switch { position: relative; width: 36px; height: 20px; border-radius: 999px; background: #1a2340; border: 1px solid var(--line-2); transition: background .2s; }
.ex-switch::after { content: ""; position: absolute; top: 2px; left: 2px; width: 14px; height: 14px; border-radius: 50%;
  background: var(--muted); transition: transform .2s, background .2s; }
.ex-toggle input:checked + .ex-switch { background: rgba(34, 211, 238, .25); border-color: rgba(34, 211, 238, .6); }
.ex-toggle input:checked + .ex-switch::after { transform: translateX(16px); background: var(--cyan); }
.ex-toggle input:focus-visible + .ex-switch { outline: 2px solid var(--cyan); outline-offset: 2px; }
.ex-chips, .ex-suggest { display: flex; flex-wrap: wrap; gap: 6px; }
.ex-chip { border: 1px solid var(--line-2); background: rgba(13, 22, 48, .55); color: var(--muted); border-radius: 999px;
  padding: 6px 12px; font: 500 0.84rem var(--body); cursor: pointer; text-align: left; }
.ex-chip:hover { color: var(--text); border-color: rgba(34, 211, 238, .5); }
.ex-chip[aria-pressed="true"] { color: var(--text); border-color: rgba(34, 211, 238, .8); background: rgba(34, 211, 238, .12); }
.ex-chip:disabled { opacity: .45; cursor: default; }
.ex-swatches { display: flex; flex-wrap: wrap; gap: 10px; }
.ex-swatch { width: 34px; height: 34px; border-radius: 50%; cursor: pointer; border: 2px solid transparent;
  background: linear-gradient(135deg, var(--a) 50%, var(--b) 50%); box-shadow: inset 0 0 0 1px rgba(255, 255, 255, .15); }
.ex-swatch[aria-pressed="true"] { border-color: #fff; box-shadow: 0 0 16px -4px var(--a); }

/* characters to pick */
.ex-people { display: grid; grid-template-columns: repeat(auto-fill, minmax(62px, 1fr)); gap: 6px; }
.ex-people.wide { grid-template-columns: repeat(auto-fill, minmax(96px, 1fr)); }
.ex-who { display: grid; gap: 3px; justify-items: center; align-content: start; padding: 5px 3px 6px; border-radius: 12px;
  border: 1px solid var(--line); background: rgba(13, 22, 48, .55); color: var(--muted); font: 500 0.8rem var(--body); cursor: pointer; }
.ex-who:hover { border-color: rgba(34, 211, 238, .45); color: var(--text); }
.ex-who[aria-pressed="true"] { border-color: rgba(34, 211, 238, .85); color: var(--text); box-shadow: 0 0 22px -8px rgba(34, 211, 238, .8); }
.ex-who img { width: 100%; max-width: 48px; aspect-ratio: 1; height: auto; border-radius: 50%; object-fit: cover; background: #0a1226; }
.ex-people:not(.wide) .ex-who-note { display: none; }
.ex-who-dot { width: 44px; height: 44px; margin: 6px 0 2px; border-radius: 50%; background: radial-gradient(circle at 35% 35%, #fff8, transparent 40%), var(--c);
  box-shadow: 0 0 18px -4px var(--c); }
.ex-who-name { line-height: 1.2; text-align: center; }
.ex-who-note { color: var(--dim); font-size: 0.72rem; line-height: 1.25; text-align: center; }

/* talking */
.ex-talk { display: grid; gap: 10px; }
.ex-talk-top { display: flex; align-items: center; gap: 10px; min-height: 34px; }
.ex-live { display: flex; align-items: center; gap: 9px; margin: 0; min-width: 0; color: var(--muted); font-size: 0.92rem; }
.ex-live-text { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.ex-dot { flex: none; width: 9px; height: 9px; border-radius: 50%; background: var(--dim); }
.ex-live[data-state="connecting"] .ex-dot { background: #fbbf24; animation: ex-pulse 1s ease-in-out infinite; }
.ex-live[data-state="ready"] .ex-dot { background: #34d399; box-shadow: 0 0 10px #34d399; }
.ex-live[data-state="thinking"] .ex-dot { background: var(--violet); animation: ex-pulse .8s ease-in-out infinite; }
.ex-live[data-state="speaking"] .ex-dot { background: var(--cyan); box-shadow: 0 0 12px var(--cyan); animation: ex-pulse .5s ease-in-out infinite; }
.ex-live[data-state="error"] { color: #fca5a5; }
.ex-live[data-state="error"] .ex-dot { background: #f87171; }
.ex-live[data-state="ready"], .ex-live[data-state="speaking"], .ex-live[data-state="thinking"] { color: var(--text); }
@keyframes ex-pulse { 50% { opacity: .35; } }
@media (prefers-reduced-motion: reduce) { .ex-dot { animation: none !important; } }
.ex-left { margin-left: auto; font: 500 0.8rem var(--mono); color: var(--dim); font-variant-numeric: tabular-nums; }
.ex-left:empty + .btn { margin-left: auto; }
.ex-talk-top .btn[hidden] { display: none; }
.ex-log { display: grid; align-content: start; gap: 8px; height: 220px; overflow-y: auto; padding: 12px; border-radius: 16px;
  border: 1px solid var(--line); background: rgba(5, 9, 22, .6); scrollbar-width: thin; overscroll-behavior: contain; }
.ex-log-empty { margin: auto 0; color: var(--dim); font-size: 0.9rem; text-align: center; padding: 0 10px; }
.ex-msg { margin: 0; max-width: 92%; padding: 8px 12px; border-radius: 14px; font-size: 0.93rem; line-height: 1.45; }
.ex-msg.you { justify-self: end; background: rgba(99, 102, 241, .18); border: 1px solid rgba(99, 102, 241, .3); border-bottom-right-radius: 4px; }
.ex-msg.face { justify-self: start; background: rgba(13, 22, 48, .9); border: 1px solid var(--line-2); border-bottom-left-radius: 4px; }
.ex-who-tag { display: block; margin-bottom: 2px; font: 500 0.66rem/1.2 var(--mono); letter-spacing: .12em; text-transform: uppercase; }
.ex-who-tag.you { color: #fde68a; }
.ex-who-tag.face { color: var(--cyan); }
.ex-form { display: flex; gap: 8px; }
.ex-say { flex: 1; min-width: 0; height: 44px; padding: 0 14px; border-radius: 12px; border: 1px solid var(--line-2);
  background: #070d1f; color: var(--text); font: 400 0.98rem var(--body); }
.ex-say::placeholder { color: var(--dim); }
.ex-say:focus-visible { outline: 2px solid var(--cyan); outline-offset: 1px; }
.ex-icon { flex: none; display: grid; place-items: center; width: 44px; height: 44px; border-radius: 12px; cursor: pointer;
  border: 1px solid var(--line-2); background: rgba(13, 22, 48, .7); color: var(--muted); }
.ex-icon svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.ex-icon:hover { color: var(--text); border-color: rgba(34, 211, 238, .5); }
.ex-icon.send { background: var(--grad); border: 0; color: #050914; }
.ex-icon.mic[aria-pressed="true"] { color: #f87171; border-color: rgba(248, 113, 113, .7); background: rgba(248, 113, 113, .1);
  box-shadow: 0 0 16px -6px rgba(248, 113, 113, .9); }
.ex-icon.mic[aria-pressed="true"] .off { display: none; }
.ex-voice { margin: 2px 0 0; }

/* the code tab */
.ex-pane .code { margin-top: 4px; }
.ex-pane .code pre { font-size: 0.78rem; padding: 14px 16px; }
.ex-links { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }

/* under the lab: where next */
.ex-next { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 14px; margin-top: 46px; }
.ex-next a { display: grid; gap: 4px; padding: 16px 18px; border-radius: 16px; border: 1px solid var(--line); text-decoration: none;
  background: rgba(13, 22, 48, .55); color: var(--muted); font-size: 0.9rem; }
.ex-next a:hover { border-color: rgba(34, 211, 238, .45); color: var(--text); }
.ex-next b { color: var(--text); font: 600 1.02rem var(--display); }
.ex-next .dir { font: 500 0.7rem var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--dim); }

/* a game's purse and a shelf of things to buy */
.ex-hud { position: absolute; top: 14px; left: 14px; display: grid; gap: 8px; margin: 0; padding: 10px 14px; border-radius: 14px;
  background: rgba(10, 18, 38, .82); border: 1px solid rgba(251, 191, 36, .4); color: var(--text); font-size: 0.9rem; }
.ex-gold { font: 600 1.2rem var(--display); color: #fbbf24; }
.ex-gold.bump { animation: ex-bump .6s ease; }
@keyframes ex-bump { 30% { transform: scale(1.25); color: #fde68a; } }
.ex-bag { display: flex; flex-wrap: wrap; gap: 6px; }
.ex-bag span { padding: 2px 8px; border-radius: 999px; border: 1px solid rgba(251, 191, 36, .35); color: #fde68a; font-size: 0.78rem; }
.ex-wares { display: grid; gap: 8px; }
.ex-ware { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: 12px; padding: 10px 12px;
  border-radius: 14px; border: 1px solid var(--line); background: rgba(13, 22, 48, .55); color: var(--muted); font-size: 0.9rem; }
.ex-ware b { display: block; color: var(--text); font-weight: 600; }
.ex-ware .icon { font-size: 1.5rem; width: 36px; height: 36px; display: grid; place-items: center; border-radius: 10px; background: #0a1226; }
.ex-ware .price { font: 600 0.95rem var(--mono); color: #fbbf24; }
.ex-ware.sold { opacity: .5; }
.ex-ware.sold .price { text-decoration: line-through; }

/* several faces at once (the museum): a wall of frames */
.ex-wall { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; padding: 22px; height: 100%; align-content: center;
  background: radial-gradient(80% 60% at 50% 0%, rgba(253, 230, 138, .08), transparent 70%), linear-gradient(180deg, #1a1420, #0d0a14); }
.ex-frame { position: relative; aspect-ratio: 4 / 5; max-height: calc((min(76vh, 700px) - 80px) / 2); justify-self: center; width: 100%;
  padding: 10px; border-radius: 6px; cursor: pointer; border: 0; display: block;
  background: linear-gradient(135deg, #8a6a2c, #e3c26b 30%, #7a5a20 60%, #d8b45a); box-shadow: 0 18px 40px -18px #000, inset 0 0 0 2px rgba(0, 0, 0, .3); }
.ex-frame canvas { display: block; width: 100%; height: 100%; border-radius: 2px; background: #000; }
.ex-frame .plate { position: absolute; left: 50%; bottom: -12px; transform: translateX(-50%); padding: 2px 10px; border-radius: 3px;
  font: 600 0.72rem var(--display); color: #2a1f0a; background: linear-gradient(180deg, #f3dd99, #c9a44a); white-space: nowrap; }
.ex-frame[aria-pressed="true"] { box-shadow: 0 0 0 3px var(--cyan), 0 0 40px -6px rgba(34, 211, 238, .8); }
.ex-frame:focus-visible { outline: 3px solid var(--cyan); outline-offset: 4px; }

@media (max-width: 960px) {
  .ex-lab { grid-template-columns: minmax(0, 1fr); }
  .ex-stage { position: relative; top: 0; height: min(64vh, 560px); }
  .ex-frame { max-height: calc((min(64vh, 560px) - 80px) / 2); }
  .ex { padding-top: 22px; }
}
@media (max-width: 520px) {
  .ex-slider { grid-template-columns: 6rem minmax(0, 1fr) 2.6rem; gap: 8px; }
  .ex-row-ctl { grid-template-columns: 6rem minmax(0, 1fr); gap: 8px; }
  .ex-stage { min-height: 320px; }
  .ex-wall { gap: 12px; padding: 14px; }
  .ex-pop { top: auto; bottom: 70px; right: 12px; }
}

/* a sound level meter on the stage (--v: 0..1, set by the page) */
.ex-meter { position: absolute; left: 16px; bottom: 16px; width: 8px; height: 120px; border-radius: 999px; background: rgba(148, 163, 184, .14); overflow: hidden; }
.ex-meter span { --v: 0; position: absolute; left: 0; right: 0; bottom: 0; height: calc(var(--v) * 100%); border-radius: inherit;
  background: linear-gradient(0deg, var(--cyan), var(--violet)); box-shadow: 0 0 12px var(--cyan); transition: height .06s linear; }
/* a photo dragged over the stage */
.ex-drop { position: absolute; inset: 12px; display: grid; place-items: center; border-radius: 16px; pointer-events: none;
  border: 2px dashed rgba(34, 211, 238, .7); background: rgba(6, 11, 24, .72); }
.ex-drop[hidden] { display: none; }
.ex-drop span { font: 600 1.1rem var(--display); color: var(--text); }
/* a call to action over the stage (the robot's "Give it a face") */
.ex-cta { position: absolute; left: 50%; bottom: 7%; transform: translateX(-50%); width: min(420px, calc(100% - 32px)); display: grid; gap: 10px;
  justify-items: center; text-align: center; padding: 18px 20px; border-radius: 16px; background: rgba(7, 10, 20, .8); border: 1px solid var(--line-2);
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px); transition: opacity .6s, transform .6s; }
.ex-cta p { margin: 0; color: var(--muted); font-size: 0.88rem; }
.ex-cta.gone { opacity: 0; transform: translate(-50%, 16px); pointer-events: none; }
/* the museum's torch: a pool of light that follows the pointer over the wall (--x, --y set by the page) */
.ex-torch { --x: 50%; --y: 40%; position: absolute; inset: 0; pointer-events: none; transition: opacity .5s;
  background: radial-gradient(circle 260px at var(--x) var(--y), transparent 0, rgba(3, 4, 10, .25) 45%, rgba(3, 4, 10, .78) 100%); }
.ex-torch.off { opacity: 0; }
/* a deck of flashcards collected in a lesson */
.ex-deck { display: grid; gap: 8px; }
.ex-flash { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 4px 12px; align-items: center; padding: 10px 14px; border-radius: 14px;
  border: 1px solid var(--line); background: rgba(13, 22, 48, .55); }
.ex-flash b { font: 600 1.02rem var(--display); color: var(--text); }
.ex-flash span { grid-column: 1; color: var(--muted); font-size: 0.88rem; }
.ex-flash button { grid-row: 1 / span 2; grid-column: 2; }
.ex-row-ctl input[type="file"]::file-selector-button { margin-right: 10px; padding: 5px 12px; border-radius: 999px; cursor: pointer;
  border: 1px solid var(--line-2); background: rgba(13, 22, 48, .7); color: var(--text); font: 500 0.84rem var(--body); }