:root{--ink:#14201b;--paper:#f5f3ed;--panel:#fffdf8;--lime:#c9fa37;--muted:#617068;--line:#d9ded7}*{box-sizing:border-box}html,body{min-height:100%;margin:0}body{background:var(--paper);color:var(--ink);font:16px/1.5 Arial,sans-serif;overflow-x:hidden}.deck{min-height:100svh;display:grid;grid-template-rows:auto 1fr auto}.deck-header{background:#14201b;color:#fff;padding:1rem max(1rem,calc((100vw - 1280px)/2));display:flex;justify-content:space-between;align-items:center;gap:1rem}.back{color:#fff;font-size:.88rem;text-decoration:none;min-height:44px;display:inline-flex;align-items:center}.eyebrow{color:var(--lime);font-size:.7rem;font-weight:700;letter-spacing:.13em;text-transform:uppercase}.count{font:700 .78rem/1 ui-monospace,monospace;color:#d7ddd8}.stage{width:min(1280px,100%);margin:auto;padding:clamp(1.25rem,3vw,2.75rem) max(1rem,calc((100vw - 1180px)/2)) calc(5.8rem + env(safe-area-inset-bottom));display:grid;place-items:center}.slide{display:none;width:100%;max-width:1120px;animation:enter .28s ease-out}.slide.is-active{display:grid;gap:1.25rem}.intro{min-height:62vh;align-content:center;max-width:850px}.intro h1{font-size:clamp(2.7rem,8vw,7rem);line-height:.88;letter-spacing:-.07em;margin:.4rem 0 1.3rem}.intro p{max-width:650px;font-size:clamp(1rem,2.1vw,1.22rem);color:var(--muted)}.notice{border-left:4px solid var(--lime);padding:1rem 1.1rem;background:#e9ece2;max-width:680px;font-size:.93rem}.screen{background:var(--panel);border:1px solid var(--line);border-radius:16px;overflow:hidden;box-shadow:0 16px 40px #17221a18}.screen img{display:block;width:100%;height:auto}.explain{display:grid;grid-template-columns:minmax(0,1fr) minmax(240px,.62fr);gap:1.25rem;align-items:start}.explain h2{font-size:clamp(1.65rem,3vw,2.5rem);line-height:1;margin:0}.explain p{margin:.55rem 0 0;color:var(--muted);max-width:600px}.slide-number{font:700 .72rem/1 ui-monospace,monospace;letter-spacing:.08em;color:#617068;text-transform:uppercase}.deck-footer,.controls{position:fixed;z-index:20;left:0;right:0;bottom:0;border-top:1px solid var(--line);background:#fffdf8f2;padding:.8rem max(1rem,calc((100vw - 1280px)/2));display:grid;grid-template-columns:44px 1fr 44px;gap:.7rem;align-items:center;backdrop-filter:blur(8px)}.nav,.controls button{width:44px;height:44px;border:1px solid #b9c1ba;background:#fff;color:var(--ink);border-radius:50%;font-size:1.25rem;cursor:pointer}.nav:disabled,.controls button:disabled{opacity:.35;cursor:not-allowed}.controls{display:flex;justify-content:space-between}.progress{height:4px;background:#dce2d9;border-radius:4px;overflow:hidden}.progress>span{height:100%;background:#14201b;display:block;transition:width .2s}.hint{text-align:center;font:.7rem/1.2 ui-monospace,monospace;color:#617068}@keyframes enter{from{opacity:.45;transform:translateY(8px)}to{opacity:1;transform:none}}@media(max-width:700px){.deck-header{padding:.75rem 1rem}.stage{align-items:start}.intro{min-height:calc(100svh - 150px)}.screen{border-radius:10px}.explain{grid-template-columns:1fr;gap:.45rem}.deck-footer{position:fixed;bottom:0;padding:.7rem 1rem;background:#fffdf8ef;backdrop-filter:blur(8px)}.hint{display:none}}@media(prefers-reduced-motion:reduce){.slide{animation:none}.progress>span{transition:none}}