/* =============================================================================
   SheetHead — Rules: tutorial demos, explorer, tabs
============================================================================= */
.rules-tabs { display: flex; flex-direction: column; align-items: center; gap: 10px; margin: 0 0 26px; text-align: center; }
.rules-tabs p { margin: 0; color: rgba(243,234,216,.66); font-size: 14.5px; }
.tabs-dark { border-color: var(--line-2); }
.tabs-dark .tab { color: var(--paper); border-right-color: var(--line-2); height: 46px; padding: 0 22px; font-size: 13px; }
.tabs-dark .tab:hover { background: rgba(243,234,216,.08); }
.tabs-dark .tab.on { background: var(--brass); color: var(--brass-ink); }

.ch-lead { font: 400 clamp(19px, 2vw, 23px)/1.3 var(--f-display); color: var(--felt) !important; margin: -2px 0 14px !important; }
.ch-sub { font: 700 12px/1 var(--f-ui); letter-spacing: .26em; text-transform: uppercase; color: var(--felt); margin: 26px 0 4px; }
.ch h2 + .ch-lead { margin-top: -6px; }
.ch > .demo:first-of-type { margin-top: 10px; }
.tip { margin: 16px 0 4px; padding: 12px 16px; border-left: 3px solid var(--brass-2); background: rgba(227,183,90,.18); border-radius: 0 8px 8px 0; }
.tip b { font: 700 10.5px var(--f-ui); letter-spacing: .24em; text-transform: uppercase; color: var(--felt); }
.tip p { margin: 4px 0 0 !important; font-size: 14.5px !important; }
.cta-row.left { justify-content: flex-start; margin-top: 18px; }
.power .card { --cw: 46px; flex: none; }
.power { align-items: flex-start; }

/* ---------- a demo: dark screen inset into the paper page ---------- */
.demo { margin: 20px 0 14px; border-radius: 12px; overflow: hidden; background: var(--ink-1); color: var(--paper); box-shadow: 0 0 0 1.5px var(--paper-ink), 0 12px 24px -12px rgba(0,0,0,.55); }
.demo-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; padding: 12px 14px 12px 16px; border-bottom: 1px solid var(--line); }
.demo-head .kicker { font-size: 10px; margin-bottom: 4px; }
.demo-head b { font: 400 20px/1.1 var(--f-display); color: var(--paper); }
.demo-ctl { display: flex; gap: 6px; flex: none; }
.demo-ctl button { width: 38px; height: 38px; border-radius: 8px; border: 1px solid var(--line-2); background: transparent; color: var(--paper); font-size: 15px; line-height: 1; cursor: pointer; transition: background .15s, border-color .15s; }
.demo-ctl button:hover:not(:disabled) { background: rgba(243,234,216,.1); border-color: var(--brass); }
.demo-ctl button:disabled { opacity: .3; cursor: default; }
.demo-stage { position: relative; container-type: inline-size; aspect-ratio: 16 / 10; overflow: hidden;
  background: radial-gradient(70% 60% at 50% 0%, rgba(227,183,90,.14), transparent 70%), linear-gradient(180deg, #170f10, #0c090b); }
.ds-table { position: absolute; left: 13%; right: 13%; top: 14%; height: 56%; border-radius: 50% / 48%; border: 6px solid #1b1412;
  background: radial-gradient(70% 60% at 50% 40%, #d8232f, #a71625 58%, #5c0a15); box-shadow: 0 0 0 2px var(--brass-2), inset 0 0 30px rgba(0,0,0,.5), 0 18px 30px -10px rgba(0,0,0,.7); }
.ds-scene { position: absolute; inset: 0; --dcw: clamp(38px, 9.4cqw, 68px); }
.ds-zone { position: absolute; transform: translate(-50%, -50%); width: var(--dcw); aspect-ratio: 5 / 7; border-radius: 8px; border: 1.5px dashed rgba(255,255,255,.28); }
.ds-zone.dash span { position: absolute; left: 0; right: 0; bottom: -18px; text-align: center; font: 700 9px var(--f-ui); letter-spacing: .22em; text-transform: uppercase; color: rgba(255,255,255,.5); }
.ds-dir { position: absolute; right: 14%; bottom: 33%; font: 700 9.5px var(--f-ui); letter-spacing: .2em; text-transform: uppercase; color: rgba(255,255,255,.45); }
.dc { position: absolute; transition: left .8s var(--ease-out), top .8s var(--ease-out), transform .8s var(--ease-out), opacity .45s ease; will-change: transform, left, top; pointer-events: none; }
.dc .card { --cw: var(--dcw); }
.demo.snap .dc, .demo.snap .ds-seat, .demo.reduced .dc { transition: none; }
.ds-seat { position: absolute; transform: translate(-50%, -50%); display: flex; flex-direction: column; align-items: center; gap: 3px; z-index: 30; transition: opacity .3s; }
.ds-plate { width: clamp(26px, 5.4cqw, 36px); aspect-ratio: 1; border-radius: 8px; display: grid; place-items: center; background: var(--paper); color: var(--paper-ink); border: 2px solid var(--paper-ink); box-shadow: 0 3px 0 var(--paper-3); font: 400 clamp(13px, 2.6cqw, 18px)/1 var(--f-display); transition: box-shadow .3s; }
.ds-name { font: 700 clamp(8px, 1.5cqw, 10px)/1 var(--f-ui); letter-spacing: .1em; text-transform: uppercase; color: rgba(243,234,216,.75); }
.ds-mark { font: 800 clamp(7.5px, 1.4cqw, 9px)/1 var(--f-ui); letter-spacing: .18em; text-transform: uppercase; padding: 3px 6px; border-radius: 4px; background: var(--brass); color: var(--brass-ink); animation: tagIn .35s var(--ease-out) both; }
.ds-mark.go { background: var(--mint); color: #04231c; } .ds-mark.no { background: #e2404d; color: #fff; }
.ds-seat.on .ds-plate { box-shadow: 0 0 0 3px var(--mint), 0 0 18px rgba(25,227,193,.75); }
.ds-seat.extra .ds-plate { box-shadow: 0 0 0 3px var(--brass), 0 0 20px rgba(227,183,90,.85); }
.ds-seat.extra .ds-mark { background: var(--brass); color: var(--brass-ink); }
.ds-seat.skip .ds-plate { opacity: .55; border-style: dashed; box-shadow: none; }
.dtag { position: absolute; transform: translate(-50%, -50%); z-index: 40; white-space: nowrap; padding: 6px 12px; border-radius: 6px; background: var(--brass); color: var(--brass-ink);
  font: 800 clamp(9px, 1.7cqw, 12px)/1 var(--f-ui); letter-spacing: .14em; text-transform: uppercase; box-shadow: 0 4px 12px rgba(0,0,0,.5); animation: tagIn .4s var(--ease-out) both; }
.dtag.no { background: #e2404d; color: #fff; }
.dtag.burn { background: linear-gradient(180deg, #ffb35a, #ff6a1a); color: #2a0e00; }
.dchips { position: absolute; transform: translate(-50%, -50%); z-index: 40; display: flex; gap: 4px; padding: 6px 8px; border-radius: 8px; background: rgba(12,9,11,.9); border: 1px solid var(--line-2); animation: tagIn .4s var(--ease-out) both; max-width: 86%; flex-wrap: wrap; justify-content: center; }
.dchips i { font-style: normal; min-width: clamp(18px, 3.4cqw, 26px); height: clamp(20px, 3.8cqw, 28px); padding: 0 4px; display: grid; place-items: center; border-radius: 4px; background: var(--paper); color: var(--paper-ink); font: 400 clamp(11px, 2.1cqw, 15px)/1 var(--f-display); transition: transform .3s, background .3s; }
.dchips i.hi { background: var(--brass); transform: scale(1.3); box-shadow: 0 0 0 2px var(--brass-ink), 0 0 14px rgba(255,213,74,.8); }
.dflame { position: absolute; z-index: 35; width: 30%; aspect-ratio: 1; transform: translate(-50%, -50%); pointer-events: none; border-radius: 50%;
  background: radial-gradient(circle, rgba(255,214,120,.95), rgba(255,110,40,.6) 40%, rgba(255,60,20,0) 70%); mix-blend-mode: screen; animation: flame 1.5s ease-out both; }
@keyframes flame { 0% { opacity: 0; transform: translate(-50%, -50%) scale(.3); } 25% { opacity: 1; } 100% { opacity: 0; transform: translate(-50%, -62%) scale(1.5); } }
@keyframes tagIn { from { opacity: 0; transform: translate(-50%, calc(-50% + 8px)) scale(.92); } to { opacity: 1; transform: translate(-50%, -50%) scale(1); } }
.ds-mark { animation-name: markIn; } @keyframes markIn { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: none; } }
.demo-cap { display: flex; gap: 14px; align-items: flex-start; padding: 14px 16px 6px; min-height: 5.6em; background: var(--ink-2); border-top: 1px solid var(--line); }
.step-n { flex: none; padding-top: 3px; font: 700 11px/1 var(--f-ui); letter-spacing: .22em; text-transform: uppercase; color: var(--brass); white-space: nowrap; }
.step-n em { font-style: normal; color: rgba(243,234,216,.45); }
.demo-cap p { margin: 0; font: 500 16px/1.5 var(--f-body); color: var(--paper); animation: capIn .4s var(--ease-out) both; }
@keyframes capIn { from { opacity: 0; transform: translateY(5px); } to { opacity: 1; transform: none; } }
.demo-dots { display: flex; gap: 4px; padding: 0 12px 6px; background: var(--ink-2); }
.demo-dots button { flex: 1; height: 26px; border: 0; background: none; cursor: pointer; position: relative; padding: 0; }
.demo-dots button::after { content: ''; position: absolute; left: 2px; right: 2px; top: 11px; height: 4px; border-radius: 2px; background: rgba(243,234,216,.2); transition: background .25s; }
.demo-dots button.done::after { background: rgba(227,183,90,.55); } .demo-dots button.on::after { background: var(--brass); }

/* ---------- explorer ---------- */
.explorer { margin: 18px 0 6px; padding: 16px; border-radius: 12px; background: var(--ink-1); color: var(--paper); box-shadow: 0 0 0 1.5px var(--paper-ink), 0 12px 24px -12px rgba(0,0,0,.55); }
.ex-top { display: flex; gap: 18px; align-items: center; flex-wrap: wrap; }
.ex-pile { display: flex; flex-direction: column; align-items: center; gap: 6px; }
.ex-pile > span { font: 700 9.5px var(--f-ui); letter-spacing: .22em; text-transform: uppercase; color: rgba(243,234,216,.6); }
.ex-empty { width: 58px; aspect-ratio: 5 / 7; border-radius: 8px; border: 1.5px dashed rgba(243,234,216,.4); display: grid; place-items: center; font: 700 10px var(--f-ui); letter-spacing: .14em; text-transform: uppercase; color: rgba(243,234,216,.6); }
.ex-pick { flex: 1; min-width: 240px; }
.ex-label { display: block; font: 700 11px var(--f-ui); letter-spacing: .22em; text-transform: uppercase; color: var(--brass); margin-bottom: 8px; }
.ex-tops { display: flex; flex-wrap: wrap; gap: 6px; }
.ex-tops button { min-width: 42px; height: 42px; padding: 0 10px; border-radius: 6px; border: 1.5px solid var(--line-2); background: transparent; color: var(--paper); font: 400 18px/1 var(--f-display); cursor: pointer; transition: background .15s, border-color .15s, transform .15s; }
.ex-tops button:first-child { font: 700 11px var(--f-ui); letter-spacing: .12em; text-transform: uppercase; }
.ex-tops button:hover { border-color: var(--brass); transform: translateY(-2px); }
.ex-tops button.on { background: var(--brass); color: var(--brass-ink); border-color: var(--brass-ink); }
.ex-hand { --exw: clamp(40px, 6.2vw, 54px); display: flex; flex-wrap: wrap; gap: 9px; justify-content: center; margin: 20px 0 10px; }
.ex-sum { margin: 8px 0 0 !important; color: var(--paper) !important; font-size: 15px !important; }
.ex-sum b { color: var(--brass-3) !important; }
.ex-note { margin: 4px 0 0 !important; color: rgba(243,234,216,.72) !important; font-size: 14px !important; }

@media (max-width: 640px) {
  .demo-head b { font-size: 17px; }
  .demo-stage { aspect-ratio: 5 / 4.6; }
  .ds-scene { --dcw: clamp(36px, 12.4cqw, 52px); }
  .ds-table { left: 15%; right: 15%; top: 15%; height: 52%; }
  .demo-cap { flex-direction: column; gap: 6px; }
  .demo-cap p { font-size: 15px; }
  .ex-hand { --exw: 40px; gap: 7px; }
}
@media (prefers-reduced-motion: reduce) { .dc { transition: none; } .dflame, .dtag, .dchips, .ds-mark, .demo-cap p { animation: none; } }
@media (max-width: 640px) {
  .book { padding: 22px 14px; }
  .demo-head { padding: 10px 10px 10px 14px; }
  .demo-head b { font-size: 16px; }
  .demo-ctl button { width: 34px; height: 34px; }
  .demo { margin-left: -2px; margin-right: -2px; }
}