:root{--primary: #4361ee;--primary-dark: #3451d1;--primary-pale: #eef0fd;--accent: #7048e8;--bg: #f0f3fb;--surface: #ffffff;--surface-2: #f7f8fc;--text: #0f172a;--text-2: #475569;--text-muted: #94a3b8;--board-outer: #2c3e8c;--board-box-gap: #4361ee;--board-cell-gap:#cbd5f5;--cell-bg: #ffffff;--cell-given: #0f172a;--cell-user: #4361ee;--cell-error: #dc2626;--cell-note: #6366f1;--hl-related: #eef0fd;--hl-selected: #c5cff8;--hl-same-num: #b4c0f6;--hl-error-bg: #fef2f2;--success: #059669;--danger: #dc2626;--danger-dark: #b91c1c;--warn: #d97706;--sh-xs: 0 1px 3px rgba(0,0,0,.07), 0 1px 2px rgba(0,0,0,.05);--sh-sm: 0 2px 8px rgba(0,0,0,.08), 0 1px 4px rgba(0,0,0,.05);--sh-md: 0 4px 20px rgba(0,0,0,.1), 0 2px 6px rgba(0,0,0,.06);--sh-lg: 0 12px 40px rgba(0,0,0,.14), 0 4px 12px rgba(0,0,0,.08);--r-sm: 6px;--r: 12px;--r-lg: 18px;--board-size: min(92vw, 96svh - 340px, 486px)}@media (prefers-color-scheme: dark){:root{--primary: #7b93f5;--primary-dark: #6175e8;--primary-pale: #1a213a;--accent: #a78bfa;--bg: #0d1117;--surface: #161b27;--surface-2: #1d2236;--text: #e8ecf8;--text-2: #94a3b8;--text-muted: #4a5568;--board-outer: #3a4f99;--board-box-gap: #3a4f99;--board-cell-gap:#222d4a;--cell-bg: #161b27;--cell-given: #e8ecf8;--cell-user: #7b93f5;--cell-error: #f87171;--cell-note: #a5b4fc;--hl-related: #1a213a;--hl-selected: #1e2f6b;--hl-same-num: #253780;--hl-error-bg: #3b1111;--success: #34d399;--danger: #f87171;--danger-dark: #ef4444}}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{-webkit-text-size-adjust:100%}body{background:var(--bg);color:var(--text);font-family:Pretendard,-apple-system,BlinkMacSystemFont,Segoe UI,Noto Sans KR,Apple SD Gothic Neo,sans-serif;font-size:16px;line-height:1.5;-webkit-font-smoothing:antialiased;min-height:100svh}button{cursor:pointer;border:none;font-family:inherit;background:none;transition:background .14s,color .14s,transform .08s,box-shadow .14s,opacity .14s}button:active:not(:disabled){transform:scale(.95)}button:disabled{cursor:not-allowed}select{font-family:inherit;cursor:pointer;-moz-appearance:none;appearance:none;-webkit-appearance:none}#app{max-width:520px;margin:0 auto;padding:12px 14px 24px;display:flex;flex-direction:column;gap:12px}.app-header{display:flex;align-items:center;justify-content:space-between;gap:10px;background:var(--surface);border-radius:var(--r);padding:10px 14px;box-shadow:var(--sh-sm)}.app-logo{display:flex;align-items:center;gap:8px;font-size:1.15rem;font-weight:800;color:var(--primary);letter-spacing:-.02em;flex-shrink:0}.logo-icon{display:grid;grid-template-columns:repeat(3,5px);grid-template-rows:repeat(3,5px);gap:2px}.logo-dot{border-radius:1px;background:var(--primary)}.logo-dot:nth-child(5){background:var(--accent)}.app-header-nav{display:flex;align-items:center;gap:6px;flex-wrap:wrap;justify-content:flex-end}.diff-select{background:var(--surface-2);color:var(--text);border:1.5px solid var(--board-cell-gap);border-radius:var(--r-sm);padding:5px 26px 5px 10px;font-size:.82rem;font-weight:600;outline:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%2394a3b8' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 8px center;transition:border-color .15s}.diff-select:focus{border-color:var(--primary)}.diff-select:hover{border-color:var(--primary)}.btn-primary{background:var(--primary);color:#fff;font-size:.82rem;font-weight:700;padding:6px 14px;border-radius:var(--r-sm);letter-spacing:.02em;box-shadow:0 2px 8px #4361ee4d}.btn-primary:hover{background:var(--primary-dark);box-shadow:0 3px 12px #4361ee66}.btn-ghost{background:transparent;color:var(--text-2);font-size:.82rem;font-weight:600;padding:6px 10px;border-radius:var(--r-sm);border:1.5px solid var(--board-cell-gap)}.btn-ghost:hover{border-color:var(--danger);color:var(--danger);background:var(--hl-error-bg)}.app-stats{display:flex;align-items:center;gap:8px;background:var(--surface);border-radius:var(--r);padding:10px 16px;box-shadow:var(--sh-xs)}.stat-pill{display:flex;align-items:center;gap:5px;flex:1;justify-content:center}.stat-pill-icon{font-size:.95rem;line-height:1}.stat-pill-body{display:flex;flex-direction:column;line-height:1.2}.stat-pill-label{font-size:.6rem;font-weight:600;text-transform:uppercase;letter-spacing:.07em;color:var(--text-muted)}.stat-pill-value{font-size:.95rem;font-weight:800;color:var(--text);font-variant-numeric:tabular-nums}.stat-divider{width:1px;height:28px;background:var(--board-cell-gap);flex-shrink:0}.stat-pill.timer-pill .stat-pill-value{color:var(--primary)}.stat-pill.diff-pill .stat-pill-value{font-size:.8rem}.app-board-wrap{position:relative;display:flex;justify-content:center;align-items:center}.board{width:var(--board-size);height:var(--board-size);display:grid;grid-template-columns:repeat(3,1fr);grid-template-rows:repeat(3,1fr);gap:3px;background:var(--board-box-gap);border:3px solid var(--board-outer);border-radius:8px;overflow:hidden;box-shadow:var(--sh-md),0 0 0 1px var(--board-outer)}.box{display:grid;grid-template-columns:repeat(3,1fr);grid-template-rows:repeat(3,1fr);gap:1px;background:var(--board-cell-gap)}.cell{background:var(--cell-bg);display:flex;align-items:center;justify-content:center;font-size:clamp(13px,3vmin,26px);font-weight:600;cursor:pointer;position:relative;outline:none;color:var(--cell-user);-webkit-user-select:none;user-select:none;transition:background .1s;-webkit-tap-highlight-color:transparent}.cell:hover:not(.given):not(.selected){background:var(--hl-related)}.cell:focus-visible{outline:2px solid var(--primary);outline-offset:-2px;z-index:2}.cell.given{color:var(--cell-given);font-weight:800;cursor:default}.cell.selected{background:var(--hl-selected)!important}.cell.highlight{background:var(--hl-related)}.cell.same-num{background:var(--hl-same-num)}.cell.error{color:var(--cell-error);background:var(--hl-error-bg)!important}.cell-num{display:block;line-height:1}.notes-grid{display:grid;grid-template-columns:repeat(3,1fr);grid-template-rows:repeat(3,1fr);width:100%;height:100%;padding:1px}.note-cell{display:flex;align-items:center;justify-content:center;font-size:clamp(6px,1.15vmin,9px);color:var(--cell-note);font-weight:700;line-height:1}@keyframes cell-pop{0%{transform:scale(1)}45%{transform:scale(1.22)}to{transform:scale(1)}}@keyframes cell-shake{0%,to{transform:translate(0)}18%{transform:translate(-5px)}36%{transform:translate(5px)}54%{transform:translate(-4px)}72%{transform:translate(4px)}86%{transform:translate(-2px)}}@keyframes board-pulse{0%{box-shadow:var(--sh-md),0 0 0 1px var(--board-outer)}50%{box-shadow:var(--sh-md),0 0 0 4px var(--success),0 0 24px #0596694d}to{box-shadow:var(--sh-md),0 0 0 1px var(--board-outer)}}.cell.anim-pop{animation:cell-pop .18s cubic-bezier(.34,1.56,.64,1)}.cell.anim-shake{animation:cell-shake .3s ease-out}.board.completed{animation:board-pulse .6s ease-out 2}.pause-overlay{position:absolute;top:0;right:0;bottom:0;left:0;border-radius:6px;background:color-mix(in srgb,var(--bg) 88%,transparent);backdrop-filter:blur(8px) saturate(.8);-webkit-backdrop-filter:blur(8px) saturate(.8);display:flex;align-items:center;justify-content:center;z-index:10;cursor:pointer;transition:opacity .2s}.pause-overlay.hidden{display:none}.pause-content{text-align:center;display:flex;flex-direction:column;align-items:center;gap:6px}.pause-icon-lg{font-size:2.8rem;line-height:1;filter:drop-shadow(0 2px 4px rgba(0,0,0,.15))}.pause-label{font-size:1.4rem;font-weight:800;color:var(--text)}.pause-hint{font-size:.82rem;color:var(--text-muted)}.app-toolbar{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.tool-btn{display:flex;flex-direction:column;align-items:center;gap:3px;padding:9px 6px 7px;border-radius:var(--r);background:var(--surface);box-shadow:var(--sh-xs);color:var(--text-2);font-size:.7rem;font-weight:700;letter-spacing:.02em;transition:background .12s,color .12s,box-shadow .12s,transform .08s}.tool-btn:hover{background:var(--primary-pale);color:var(--primary);box-shadow:var(--sh-sm)}.tool-btn .tool-icon{font-size:1.35rem;line-height:1}.tool-btn.active{background:var(--primary);color:#fff;box-shadow:0 3px 12px #4361ee59}.app-numpad-wrap{background:var(--surface);border-radius:var(--r);padding:14px;box-shadow:var(--sh-sm)}.numpad-grid{display:grid;grid-template-columns:repeat(9,1fr);gap:6px}.num-btn{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:2px;aspect-ratio:1;border-radius:10px;background:var(--primary-pale);color:var(--primary);transition:background .12s,color .12s,box-shadow .12s,transform .08s,opacity .15s}.num-btn:hover:not(:disabled){background:var(--hl-selected);box-shadow:var(--sh-sm);transform:translateY(-1px) scale(1.04)}.num-btn:active:not(:disabled){transform:scale(.93)}.num-digit{font-size:clamp(1rem,3.5vw,1.5rem);font-weight:800;line-height:1}.num-count{font-size:.58rem;font-weight:700;opacity:.55;line-height:1;min-height:.7em}.num-btn.exhausted{opacity:.25;pointer-events:none}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#0000008c;backdrop-filter:blur(4px);-webkit-backdrop-filter:blur(4px);display:flex;align-items:center;justify-content:center;z-index:200;padding:16px}.modal-overlay.hidden{display:none}@keyframes modal-in{0%{opacity:0;transform:scale(.9) translateY(8px)}to{opacity:1;transform:scale(1) translateY(0)}}.modal-box{background:var(--surface);border-radius:var(--r-lg);padding:32px 28px 28px;width:100%;max-width:360px;box-shadow:var(--sh-lg);text-align:center;animation:modal-in .22s cubic-bezier(.34,1.2,.64,1)}@keyframes trophy-bounce{0%,to{transform:translateY(0) rotate(-3deg)}50%{transform:translateY(-8px) rotate(3deg)}}.completed-modal .modal-trophy{font-size:3.5rem;margin-bottom:10px;display:inline-block;animation:trophy-bounce 1s ease-in-out infinite}.completed-modal h2{font-size:1.7rem;font-weight:900;color:var(--success);margin-bottom:4px}.completed-subtitle{color:var(--text-muted);font-size:.88rem;margin-bottom:20px}.completed-stats{background:var(--surface-2);border-radius:var(--r);overflow:hidden;margin-bottom:20px;border:1px solid var(--board-cell-gap)}.stat-row{display:flex;justify-content:space-between;align-items:center;padding:9px 16px;font-size:.88rem;color:var(--text-2)}.stat-row:not(:last-child){border-bottom:1px solid var(--board-cell-gap)}.stat-row strong{font-weight:800;color:var(--text);font-size:.95rem}.btn-play-again{width:100%;padding:13px;background:var(--primary);color:#fff;font-size:1rem;font-weight:800;border-radius:var(--r);letter-spacing:.02em;box-shadow:0 4px 16px #4361ee59}.btn-play-again:hover{background:var(--primary-dark)}.confirm-modal p{color:var(--text-2);margin-bottom:20px;font-size:.9rem;line-height:1.6}.modal-btn-row{display:flex;gap:8px}.modal-btn-row>*{flex:1;padding:10px;border-radius:var(--r-sm);font-weight:700;font-size:.88rem}.modal-btn-danger{background:var(--danger);color:#fff}.modal-btn-danger:hover{background:var(--danger-dark)}.modal-btn-cancel{background:var(--surface-2);color:var(--text);border:1.5px solid var(--board-cell-gap)}.modal-btn-cancel:hover{border-color:var(--primary);color:var(--primary)}@keyframes spin{to{transform:rotate(360deg)}}.generating-wrap{display:flex;flex-direction:column;align-items:center;gap:14px;padding:8px}.generating-spinner{width:36px;height:36px;border:3px solid var(--board-cell-gap);border-top-color:var(--primary);border-radius:50%;animation:spin .7s linear infinite}.generating-text{font-size:.9rem;color:var(--text-muted);font-weight:600}@media (max-width: 400px){:root{--board-size: min(94vw, 400px)}#app{padding:8px 10px 20px;gap:10px}.app-header{padding:8px 12px}.app-logo{font-size:1rem}.numpad-grid{gap:4px}.app-toolbar{gap:6px}.tool-btn{padding:7px 4px 6px;font-size:.65rem}.tool-btn .tool-icon{font-size:1.15rem}}@media (max-height: 600px){:root{--board-size: min(88vw, 56vh)}#app{gap:8px;padding-top:8px;padding-bottom:12px}}