:root{
  --bg:#f5f4f0; --surface:#fbfbf9; --panel:#ffffff; --panel-soft:#f7f6f2;
  --ink:#1c1c1a; --ink-hover:#3a3935; --ink-2:#55534d; --sub:#7a776f; --muted:#8a877f;
  --line:#e3e1db; --line-2:#dcdad3; --line-3:#efeee9; --hover:#efeee9; --soft:#f3f2ee; --track:#ebe9e3;
  --accent:#1c1c1a;
  --font:"IBM Plex Sans KR",sans-serif; --mono:"JetBrains Mono",monospace;
}
*{box-sizing:border-box}
[hidden]{display:none !important}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--font);-webkit-font-smoothing:antialiased}
button{font:inherit;color:inherit}
.mono-label{font-family:var(--mono);font-size:11px;letter-spacing:.12em;color:var(--muted)}
.app{min-height:calc(100vh - 48px);display:flex;flex-direction:column}
.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:16px 28px;border-bottom:1px solid var(--line);background:var(--surface);flex-wrap:wrap}
.brand{display:flex;align-items:baseline;gap:14px;min-width:0;flex-wrap:wrap}
.home{font-size:13px;color:var(--ink-2);text-decoration:none}
.home:hover{color:var(--ink)}
.brand-title{font-size:17px;font-weight:700;letter-spacing:-.01em}
.btn{height:36px;padding:0 14px;background:transparent;border:1px solid var(--line-2);border-radius:999px;font-size:13px;cursor:pointer}
.btn:hover{background:var(--hover)}
.btn:disabled{opacity:.4;cursor:default}
.btn:disabled:hover{background:transparent}
.btn--solid{background:var(--ink);color:#fff;border:none;font-weight:500}
.btn--solid:hover{background:var(--ink-hover)}
.text-input{height:40px;padding:0 12px;background:var(--surface);border:1px solid var(--line-2);border-radius:8px;font:inherit;font-size:14px;color:var(--ink)}
@media (max-width:640px){ .topbar{padding:14px 16px} }

/* ---------- 게임 공통 셸 ---------- */
.actions{display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.btn--accent{background:var(--accent);color:#fff;border:none;font-weight:500}
.btn--accent:hover{background:var(--accent);filter:brightness(1.08)}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.game{flex:1;display:flex;flex-wrap:wrap;align-items:stretch;min-height:0}
.stage{flex:999 1 420px;min-width:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:20px;padding:40px 28px}
.side{flex:1 1 300px;min-width:0;max-width:100%;border-left:1px solid var(--line);background:var(--panel);padding:28px 24px 40px;display:flex;flex-direction:column;gap:28px}
.group{display:flex;flex-direction:column;gap:12px}
.group + .group{border-top:1px solid var(--line-3);padding-top:24px}
.rules{margin:0;padding:0;list-style:none;display:flex;flex-direction:column;gap:8px;font-size:13px;color:var(--ink-2);line-height:1.6;counter-reset:rule}
.rules li{display:flex;gap:10px}
.rules li::before{counter-increment:rule;content:counter(rule,decimal-leading-zero);font-family:var(--mono);font-size:11px;color:var(--accent);padding-top:3px;flex-shrink:0}
.keys{display:flex;flex-direction:column;gap:8px;font-size:12px;color:var(--ink-2)}
.keys div{display:flex;justify-content:space-between;align-items:center;gap:12px}
.kbd{display:inline-block;font-family:var(--mono);font-size:11px;line-height:1.4;padding:1px 6px;border:1px solid var(--line-2);border-bottom-width:2px;border-radius:5px;background:var(--surface);color:var(--ink)}
.best-card{display:flex;align-items:baseline;justify-content:space-between;gap:12px;padding:16px;border-radius:12px;background:var(--panel-soft)}
.best-val{font-family:var(--mono);font-size:28px;font-weight:500;letter-spacing:-.02em}
.seg{display:flex;background:var(--soft);border-radius:999px;padding:3px;gap:2px}
.seg-btn{flex:1;height:30px;padding:0 10px;background:transparent;color:var(--sub);border:none;border-radius:999px;font-size:12px;cursor:pointer;white-space:nowrap}
.seg-btn.is-active{background:#fff;color:var(--ink);box-shadow:0 1px 3px rgba(0,0,0,.12)}
.link-btn{padding:0;background:none;border:none;font-size:12px;color:var(--muted);text-decoration:underline;text-underline-offset:3px;cursor:pointer}
@media (max-width:640px){
  .stage{padding:24px 16px}
  .side{border-left:none;border-top:1px solid var(--line);padding:24px 16px 40px}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms !important;animation-iteration-count:1 !important;transition-duration:.01ms !important}
}


/* ---------- 슬라이드 퍼즐 (청록 트레이 + 크림 조각) ---------- */
:root{--accent:#0f9d84;--tray:#0e3b37;--tray-2:#154c47;--tile:#fff9ee;--tile-edge:#e6dcc6}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.stage{gap:16px;background:radial-gradient(90% 60% at 50% 30%,#e3f2ee 0%,var(--bg) 70%)}
.controls{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;width:min(100%,460px)}
.controls .seg{flex:1 1 180px}
.photo-bar{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:8px 14px;width:min(100%,460px);padding:12px 14px;border-radius:14px;background:var(--panel);border:1px dashed var(--line-2)}
.upload{display:inline-flex;align-items:center;background:var(--accent);color:#fff;border:none;font-weight:500}
.upload:hover{background:var(--accent);filter:brightness(1.08)}
#fileInput:focus-visible + .check,.photo-bar:focus-within .upload{outline:2px solid var(--accent);outline-offset:2px}
.check{display:flex;align-items:center;gap:6px;font-size:13px;color:var(--ink-2);cursor:pointer}
.check input{width:16px;height:16px;accent-color:var(--accent)}
.photo-note{flex-basis:100%;text-align:center;font-size:11.5px;color:var(--muted)}

.stats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px;width:min(100%,460px)}
.stat{display:flex;flex-direction:column;align-items:center;gap:2px;padding:10px 8px;border-radius:12px;background:var(--panel);border:1px solid var(--line)}
.stat b{font-family:var(--mono);font-size:22px;font-weight:700;font-variant-numeric:tabular-nums;line-height:1.15}
.stat--best{background:var(--tray);border-color:var(--tray)}
.stat--best .mono-label{color:#7fb7ad}
.stat--best b{color:#fff}

.tray{position:relative;width:min(100%,460px);aspect-ratio:1;padding:10px;border-radius:24px;background:linear-gradient(150deg,var(--tray-2),var(--tray));box-shadow:inset 0 2px 0 rgba(255,255,255,.08),0 2px 0 #08221f,0 30px 56px -26px rgba(15,157,132,.55)}
.board{position:relative;width:100%;height:100%;border-radius:14px;background:rgba(0,0,0,.18);touch-action:none;user-select:none;-webkit-user-select:none;outline:none}
.board:focus-visible{box-shadow:0 0 0 3px #ffd36b}
.tile{--x:0;--y:0;position:absolute;left:0;top:0;width:calc(100% / var(--n));height:calc(100% / var(--n));padding:3px;border:none;background:transparent;cursor:pointer;transform:translate(calc(var(--x) * 100%),calc(var(--y) * 100%));transition:transform .13s cubic-bezier(.3,.7,.4,1);-webkit-tap-highlight-color:transparent;font:inherit}
.tile::before{content:"";position:absolute;inset:3px;border-radius:10px;background:var(--tile);box-shadow:inset 0 -4px 0 var(--tile-edge),0 2px 0 rgba(0,0,0,.25)}
.tile-num{position:relative;display:flex;align-items:center;justify-content:center;width:100%;height:100%;padding-bottom:3px;font-family:var(--mono);font-weight:800;font-size:calc(min(100vw,460px) / var(--n) * .36);color:#2a3532;letter-spacing:-.04em}
.tile.is-home .tile-num{color:var(--accent)}
.tile.is-home::after{content:"";position:absolute;right:10px;top:10px;width:6px;height:6px;border-radius:50%;background:var(--accent)}
.tile:hover::before{background:#fffdf7}
.board[data-n="5"] .tile::before{border-radius:8px}
/* 사진 모드 */
.board.is-photo .tile{background-size:calc(var(--n) * 100%) calc(var(--n) * 100%);background-position:var(--bx) var(--by);background-origin:content-box;background-clip:content-box;background-repeat:no-repeat}
.board.is-photo .tile{border-radius:10px}
.board.is-photo .tile::before{display:none}
.board.is-photo .tile{box-shadow:none}
.board.is-photo .tile-num{display:none}
.board.is-photo.show-num .tile-num{display:flex;align-items:flex-start;justify-content:flex-start;padding:6px 8px;font-size:12px;color:#fff;text-shadow:0 1px 2px rgba(0,0,0,.8)}
.board.is-photo .tile.is-home::after{background:#fff;box-shadow:0 0 0 2px var(--accent)}

.peek{position:absolute;inset:10px;border-radius:14px;z-index:3;display:grid;grid-template-columns:repeat(var(--n),1fr);gap:6px;padding:6px;background:var(--tray);animation:fade .15s}
.peek span{display:flex;align-items:center;justify-content:center;border-radius:8px;background:rgba(255,255,255,.12);color:#fff;font-family:var(--mono);font-weight:800;font-size:clamp(12px,3.4vw,20px)}
.peek .peek-blank{background:transparent;border:2px dashed rgba(255,255,255,.2)}
.peek.is-photo{display:block;padding:0;background-size:cover;background-position:center}
.cover{position:absolute;inset:10px;z-index:4;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:10px;padding:20px;border-radius:14px;text-align:center;background:rgba(14,59,55,.9);color:#fff;backdrop-filter:blur(6px)}
.cover .mono-label{color:#7fe3cf;font-weight:700}
.cover strong{font-size:clamp(22px,6vw,30px);letter-spacing:-.02em}
.cover p{margin:0;font-size:13px;color:#cfe7e2;word-break:keep-all}
.cover--win{background:rgba(14,59,55,.82);animation:fade .3s}
.cover--win strong{font-family:var(--mono)}
@keyframes fade{from{opacity:0}}

.under{display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:8px 14px;width:min(100%,460px)}
#peekBtn{touch-action:none;user-select:none;-webkit-user-select:none}
#peekBtn.is-on{background:var(--tray);color:#fff;border-color:var(--tray)}
.hint-text{font-size:12px;color:var(--muted);text-align:center;word-break:keep-all}

.records{display:flex;flex-direction:column;gap:8px}
.rec{display:grid;grid-template-columns:44px 1fr 1fr auto;align-items:baseline;gap:8px;padding:10px 12px;border-radius:10px;background:var(--panel-soft);font-size:12px;color:var(--ink-2)}
.rec.is-cur{background:#e3f2ee}
.rec-size{font-family:var(--mono);font-weight:700;color:var(--ink)}
.rec b{font-family:var(--mono);font-size:15px;font-weight:700;color:var(--ink);margin-right:2px}
.rec-cnt{color:var(--muted);font-size:11px}
.rec-empty{grid-column:2 / -1;color:var(--muted)}
.app[data-state="won"] .tile{cursor:default}
@media (max-width:640px){
  .stage{padding:16px 16px 24px}
  .tray{padding:7px;border-radius:18px}
  .peek,.cover{inset:7px}
  .tile{padding:2px}
  .tile::before{inset:2px;border-radius:8px}
}

/* 다크 모드 (인쇄는 라이트 그대로): 트레이는 원래 어두우니 테두리만, 크림 조각은 눈부시지 않게 한 톤 낮춤 */
@media screen{
  :root[data-theme="dark"]{
    color-scheme:dark;
    --bg:#111615; --surface:#161c1b; --panel:#1a2120; --panel-soft:#1f2726;
    --ink:#e7eeec; --ink-hover:#ffffff; --ink-2:#c3cdca; --sub:#99a6a2; --muted:#84918d;
    --line:#283130; --line-2:#323c3a; --line-3:#212928; --hover:#232c2a; --soft:#212928; --track:#2f3937;
    --accent:#3cc6a9; --tile:#cfc5b0; --tile-edge:#a79c84;
  }
  :root[data-theme="dark"] .btn--solid{color:var(--bg)}
  :root[data-theme="dark"] .seg-btn.is-active{background:var(--track);box-shadow:0 1px 3px rgba(0,0,0,.4)}
  :root[data-theme="dark"] .upload{background:#0f9d84}
  :root[data-theme="dark"] .stage{background:radial-gradient(90% 60% at 50% 30%,#16302b 0%,var(--bg) 70%)}
  :root[data-theme="dark"] .stat--best{border-color:#1d5650}
  :root[data-theme="dark"] .tray{box-shadow:0 0 0 1px #1d5650,inset 0 2px 0 rgba(255,255,255,.08),0 2px 0 #08221f,0 30px 56px -26px rgba(15,157,132,.35)}
  :root[data-theme="dark"] .tile.is-home .tile-num{color:#0b7a66}
  :root[data-theme="dark"] .tile.is-home::after{background:#0b7a66}
  :root[data-theme="dark"] .board.is-photo .tile.is-home::after{background:#fff}
  :root[data-theme="dark"] .tile:hover::before{background:#dbd2bf}
  :root[data-theme="dark"] #peekBtn.is-on{border-color:#1d5650}
  :root[data-theme="dark"] .rec.is-cur{background:#173a35}
}