@layer properties{@supports (((-webkit-hyphens:none)) and (not (margin-trim:inline))) or ((-moz-orient:inline) and (not (color:rgb(from red r g b)))){*,:before,:after,::backdrop{--tw-blur:initial;--tw-brightness:initial;--tw-contrast:initial;--tw-grayscale:initial;--tw-hue-rotate:initial;--tw-invert:initial;--tw-opacity:initial;--tw-saturate:initial;--tw-sepia:initial;--tw-drop-shadow:initial;--tw-drop-shadow-color:initial;--tw-drop-shadow-alpha:100%;--tw-drop-shadow-size:initial}}}@layer theme{:root,:host{--font-sans:ui-sans-serif, system-ui, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";--font-mono:ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;--default-font-family:var(--font-sans);--default-mono-font-family:var(--font-mono)}}@layer base{*,:after,:before,::backdrop{box-sizing:border-box;border:0 solid;margin:0;padding:0}::file-selector-button{box-sizing:border-box;border:0 solid;margin:0;padding:0}html,:host{-webkit-text-size-adjust:100%;tab-size:4;line-height:1.5;font-family:var(--default-font-family,ui-sans-serif, system-ui, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji");font-feature-settings:var(--default-font-feature-settings,normal);font-variation-settings:var(--default-font-variation-settings,normal);-webkit-tap-highlight-color:transparent}hr{height:0;color:inherit;border-top-width:1px}abbr:where([title]){-webkit-text-decoration:underline dotted;text-decoration:underline dotted}h1,h2,h3,h4,h5,h6{font-size:inherit;font-weight:inherit}a{color:inherit;-webkit-text-decoration:inherit;text-decoration:inherit}b,strong{font-weight:bolder}code,kbd,samp,pre{font-family:var(--default-mono-font-family,ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace);font-feature-settings:var(--default-mono-font-feature-settings,normal);font-variation-settings:var(--default-mono-font-variation-settings,normal);font-size:1em}small{font-size:80%}sub,sup{vertical-align:baseline;font-size:75%;line-height:0;position:relative}sub{bottom:-.25em}sup{top:-.5em}table{text-indent:0;border-color:inherit;border-collapse:collapse}:-moz-focusring{outline:auto}progress{vertical-align:baseline}summary{display:list-item}ol,ul,menu{list-style:none}img,svg,video,canvas,audio,iframe,embed,object{vertical-align:middle;display:block}img,video{max-width:100%;height:auto}button,input,select,optgroup,textarea{font:inherit;font-feature-settings:inherit;font-variation-settings:inherit;letter-spacing:inherit;color:inherit;opacity:1;background-color:#0000;border-radius:0}::file-selector-button{font:inherit;font-feature-settings:inherit;font-variation-settings:inherit;letter-spacing:inherit;color:inherit;opacity:1;background-color:#0000;border-radius:0}:where(select:is([multiple],[size])) optgroup{font-weight:bolder}:where(select:is([multiple],[size])) optgroup option{padding-inline-start:20px}::file-selector-button{margin-inline-end:4px}::placeholder{opacity:1}@supports (not ((-webkit-appearance:-apple-pay-button))) or (contain-intrinsic-size:1px){::placeholder{color:currentColor}@supports (color:color-mix(in lab,red,red)){::placeholder{color:color-mix(in oklab,currentcolor 50%,transparent)}}}textarea{resize:vertical}::-webkit-search-decoration{-webkit-appearance:none}::-webkit-date-and-time-value{min-height:1lh;text-align:inherit}::-webkit-datetime-edit{display:inline-flex}::-webkit-datetime-edit-fields-wrapper{padding:0}::-webkit-datetime-edit{padding-block:0}::-webkit-datetime-edit-year-field{padding-block:0}::-webkit-datetime-edit-month-field{padding-block:0}::-webkit-datetime-edit-day-field{padding-block:0}::-webkit-datetime-edit-hour-field{padding-block:0}::-webkit-datetime-edit-minute-field{padding-block:0}::-webkit-datetime-edit-second-field{padding-block:0}::-webkit-datetime-edit-millisecond-field{padding-block:0}::-webkit-datetime-edit-meridiem-field{padding-block:0}::-webkit-calendar-picker-indicator{line-height:1}:-moz-ui-invalid{box-shadow:none}button,input:where([type=button],[type=reset],[type=submit]){appearance:button}::file-selector-button{appearance:button}::-webkit-inner-spin-button{height:auto}::-webkit-outer-spin-button{height:auto}[hidden]:where(:not([hidden=until-found])){display:none!important}}@layer components;@layer utilities{.invisible{visibility:hidden}.visible{visibility:visible}.container{width:100%}@media(min-width:40rem){.container{max-width:40rem}}@media(min-width:48rem){.container{max-width:48rem}}@media(min-width:64rem){.container{max-width:64rem}}@media(min-width:80rem){.container{max-width:80rem}}@media(min-width:96rem){.container{max-width:96rem}}.grid{display:grid}.hidden{display:none}.inline{display:inline}.italic{font-style:italic}.filter{filter:var(--tw-blur,) var(--tw-brightness,) var(--tw-contrast,) var(--tw-grayscale,) var(--tw-hue-rotate,) var(--tw-invert,) var(--tw-saturate,) var(--tw-sepia,) var(--tw-drop-shadow,)}}:root{--board-max:560px;--bg:#f5f7fa;--bg-soft:#eef1f6;--surface:#fff;--ink:#2a2f38;--ink-soft:#6b7280;--accent:#3b6ea5;--accent-ink:#fff;--ring:#2a2f381f;--shadow:0 1px 2px #2a2f3814, 0 8px 24px #2a2f380f;--board-line:#2a2f38;--grid-line:#2a2f382e;--cell-bg:#fff;--cell-given-ink:#2a2f38;--cell-entry-ink:#2c5c8f;--cell-conflict-bg:#f7d7d7;--cell-conflict-ink:#c0392b;--cell-selected-bg:#cfe0f3;--cell-peer-bg:#eaf0f7;--cell-same-bg:#d3e4f5;--note-ink:#6b7280}[data-theme=dark]{--bg:#14171c;--bg-soft:#1a1e25;--surface:#1e232b;--ink:#e8ebf0;--ink-soft:#9aa3b0;--accent:#6ea3dd;--accent-ink:#14171c;--ring:#e8ebf01f;--shadow:0 1px 2px #0006, 0 10px 30px #0000004d;--board-line:#e8ebf0;--grid-line:#e8ebf02e;--cell-bg:#1e232b;--cell-given-ink:#e8ebf0;--cell-entry-ink:#a3c8f2;--cell-conflict-bg:#4a2326;--cell-conflict-ink:#f0a0a0;--cell-selected-bg:#2e4258;--cell-peer-bg:#242c36;--cell-same-bg:#34506e;--note-ink:#9aa3b0}*{box-sizing:border-box}html{background:var(--bg)}body{min-height:100dvh;font-family:var(--font-ui);color:var(--ink);background:radial-gradient(120% 80% at 50% -10%,var(--bg-soft),transparent 60%),var(--bg);-webkit-font-smoothing:antialiased;text-rendering:optimizelegibility;flex-direction:column;margin:0;display:flex}a{color:inherit}:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.site-header{justify-content:space-between;align-items:center;gap:1rem;width:100%;max-width:1100px;margin:0 auto;padding:1rem clamp(1rem,4vw,2rem);display:flex}.brand{font-family:var(--font-brand);letter-spacing:-.02em;color:var(--ink);font-size:1.4rem;font-weight:600;text-decoration:none}.brand span{color:var(--accent)}.header-actions{align-items:center;gap:.5rem;display:flex}.icon-btn{border:1px solid var(--ring);background:var(--surface);width:2.4rem;height:2.4rem;color:var(--ink);cursor:pointer;box-shadow:var(--shadow);border-radius:.8rem;place-items:center;transition:transform .12s,background .2s;display:inline-grid}.icon-btn:hover{transform:translateY(-1px)}.icon-btn:active{transform:translateY(0)}.icon-btn .sun{display:none}[data-theme=dark] .icon-btn .sun{display:block}[data-theme=dark] .icon-btn .moon{display:none}.lang-switch{border:1px solid var(--ring);background:var(--surface);box-shadow:var(--shadow);border-radius:.8rem;align-items:center;gap:.15rem;padding:.2rem;display:inline-flex}.lang-link{letter-spacing:.02em;min-width:2.4rem;min-height:2.4rem;color:var(--ink-soft);border-radius:.6rem;place-items:center;padding:0 .6rem;font-size:.85rem;font-weight:600;text-decoration:none;transition:background .15s,color .15s;display:inline-grid}.lang-link:hover{color:var(--ink)}.lang-link[aria-current=true]{background:var(--accent);color:var(--accent-ink)}main{flex:1;width:100%;max-width:1100px;margin:0 auto;padding:.5rem clamp(1rem,4vw,2rem) 3rem}.page-title{text-align:center;font-family:var(--font-brand);color:var(--ink-soft);letter-spacing:-.01em;margin:.25rem 0 .9rem;font-size:1.15rem;font-weight:600}.btn{font-family:var(--font-ui);cursor:pointer;background:var(--accent);color:var(--accent-ink);box-shadow:var(--shadow);white-space:nowrap;border:none;border-radius:.9rem;padding:.7rem 1.1rem;font-weight:600;transition:transform .12s,filter .2s}.btn:hover{filter:brightness(1.04);transform:translateY(-1px)}.btn:active{transform:translateY(0)}.btn.ghost{background:var(--surface);color:var(--ink);border:1px solid var(--ring)}.ad-slot{border-radius:.8rem;display:block;overflow:hidden}.ad-slot--below{max-width:480px;min-height:90px;margin:1.5rem auto}.site-footer{border-top:1px solid var(--ring);text-align:center;width:100%;max-width:1100px;color:var(--ink-soft);flex-direction:column;align-items:center;gap:.75rem;margin:0 auto;padding:1.5rem clamp(1rem,4vw,2rem);font-size:.85rem;display:flex}.site-footer a{text-decoration:none}.site-footer a:hover{color:var(--accent)}.footer-links{flex-wrap:wrap;justify-content:center;gap:.5rem 1.25rem;display:flex}.footer-links a{color:var(--ink);text-underline-offset:.2em;text-decoration:underline;-webkit-text-decoration-color:var(--ring);text-decoration-color:var(--ring)}.footer-links a:hover{-webkit-text-decoration-color:var(--accent);text-decoration-color:var(--accent)}.footer-crosspromo{flex-wrap:wrap;justify-content:center;align-items:center;gap:.2rem .5rem;display:flex}.crosspromo-heading{color:var(--ink-soft)}.crosspromo-link{color:var(--accent);text-underline-offset:.2em;text-decoration:underline;-webkit-text-decoration-color:var(--accent);text-decoration-color:var(--accent);padding:.35rem .5rem;font-weight:600;text-decoration-thickness:1px}.crosspromo-link:hover{text-decoration-thickness:2px}.content{max-width:46rem}.breadcrumb{color:var(--ink-soft);flex-wrap:wrap;align-items:center;gap:.4rem;margin:.25rem 0 1rem;font-size:.85rem;display:flex}.breadcrumb a{color:var(--accent);text-decoration:none}.breadcrumb a:hover{text-decoration:underline}.breadcrumb .sep{color:var(--ring)}.prose{color:var(--ink);line-height:1.65}.prose h1{font-family:var(--font-brand);letter-spacing:-.02em;margin:0 0 1rem;font-size:clamp(1.6rem,5vw,2.1rem);font-weight:600}.prose h2{font-family:var(--font-brand);margin:1.8rem 0 .6rem;font-size:1.25rem;font-weight:600}.prose p{margin:0 0 1rem}.prose ul{margin:0 0 1rem;padding-left:1.4rem;list-style:outside}.prose li{margin:.3rem 0}.prose li::marker{color:var(--accent)}.prose a{color:var(--accent);text-underline-offset:.2em;text-decoration:underline}.prose strong{font-weight:600}.prose code{background:var(--surface);border:1px solid var(--ring);border-radius:.4rem;padding:.05em .35em;font-size:.9em}.content-updated{color:var(--ink-soft);margin-top:2rem;font-size:.85rem}.sudoku{width:100%;max-width:var(--board-max);flex-direction:column;gap:1rem;margin:0 auto;display:flex}.difficulty{gap:.4rem;display:flex}.diff-tab{font-family:var(--font-ui);border:1px solid var(--ring);background:var(--surface);color:var(--ink-soft);cursor:pointer;border-radius:.7rem;flex:1;padding:.55rem .3rem;font-size:.9rem;font-weight:600;transition:background .18s,color .18s;position:relative}.diff-tab[data-active]{background:var(--accent);color:var(--accent-ink);border-color:var(--accent)}.diff-badge{opacity:.9;font-size:.72rem;font-weight:600;display:block}.game-bar{gap:.6rem;display:flex}.stat{background:var(--surface);border:1px solid var(--ring);text-align:center;border-radius:.8rem;flex:1;padding:.45rem .6rem}.stat-label{color:var(--ink-soft);font-size:.7rem;display:block}.stat-value{font-variant-numeric:tabular-nums;font-size:1.05rem;font-weight:600}.board{--chrome:21rem;width:min(100%,max(calc(100svh - var(--chrome)),17rem));aspect-ratio:1;background:var(--cell-bg);border:2px solid var(--board-line);border-radius:.4rem;margin:0 auto;position:relative;overflow:hidden;container-type:inline-size}.cells{grid-template-columns:repeat(9,1fr);width:100%;height:100%;display:grid}.cell{aspect-ratio:1;border:.5px solid var(--grid-line);background:var(--cell-bg);color:var(--cell-entry-ink);font-family:var(--font-ui);cursor:pointer;place-items:center;padding:0;font-size:max(1.1rem,6cqi);font-weight:500;transition:background .12s;display:grid;position:relative}.cell.region-right{border-right:2px solid var(--board-line)}.cell.region-bottom{border-bottom:2px solid var(--board-line)}.cell[data-given]{color:var(--cell-given-ink);cursor:default;font-weight:700}.cell[data-peer]{background:var(--cell-peer-bg)}.cell[data-same]{background:var(--cell-same-bg)}.cell[data-selected]{background:var(--cell-selected-bg);outline:2px solid var(--accent);outline-offset:-2px;z-index:1}.cell[data-conflict]{background:var(--cell-conflict-bg);color:var(--cell-conflict-ink)}.cell-value{line-height:1}.cell-notes{pointer-events:none;grid-template-rows:repeat(3,1fr);grid-template-columns:repeat(3,1fr);display:grid;position:absolute;inset:6%}.cell-notes [data-note]{color:var(--note-ink);place-items:center;font-size:max(.5rem,2.4cqi);font-weight:500;line-height:1;display:grid}.confetti-layer{pointer-events:none;z-index:2;position:absolute;inset:0;overflow:hidden}.confetti{bottom:0;left:var(--x0);opacity:0;width:.55rem;height:.8rem;animation:confetti-burst var(--life) ease-out var(--delay) forwards;border-radius:1px;position:absolute}@keyframes confetti-burst{0%{opacity:1;transform:translate(0)rotate(0)}to{transform:translate(var(--dx),calc(var(--peak) * -1 + 110cqi)) rotate(var(--rot));opacity:0}}@media(prefers-reduced-motion:reduce){.confetti{bottom:auto;top:var(--x0);animation:confetti-fade 1.2s ease-out var(--delay) forwards}@keyframes confetti-fade{0%{opacity:.9}to{opacity:0}}}.controls{flex-direction:column;gap:.7rem;display:flex}.pad{grid-template-columns:repeat(9,1fr);gap:.35rem;display:grid}.pad-btn{min-height:2.9rem;font-family:var(--font-ui);border:1px solid var(--ring);background:var(--surface);color:var(--ink);cursor:pointer;font-variant-numeric:tabular-nums;border-radius:.6rem;font-size:1.2rem;font-weight:600;transition:background .12s,transform .1s}.pad-btn:hover{background:var(--bg-soft)}.pad-btn:active{transform:translateY(1px)}@media(max-width:420px){.pad{grid-template-columns:repeat(9,1fr);gap:.2rem}.pad-btn{min-height:2.6rem;font-size:1rem}}.actions{flex-wrap:wrap;justify-content:center;gap:.5rem;display:flex}.actions .btn{min-height:2.6rem}.notes-btn[aria-pressed=true]{background:var(--accent);color:var(--accent-ink);border-color:var(--accent)}.overlay{background:var(--bg);place-items:center;display:grid;position:absolute;inset:0}@supports (color:color-mix(in lab,red,red)){.overlay{background:color-mix(in srgb,var(--bg) 80%,transparent)}}.overlay{-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px);opacity:0;pointer-events:none;transition:opacity .25s}.overlay[data-open=true]{opacity:1;pointer-events:auto}.overlay-card{text-align:center;background:var(--surface);border:1px solid var(--ring);box-shadow:var(--shadow);border-radius:1rem;max-width:80%;padding:1.5rem}.overlay-card h2{font-family:var(--font-brand);margin:0 0 .5rem;font-size:1.8rem}.overlay-card p{color:var(--ink-soft);margin:0 0 1rem}@media(max-height:820px){main{padding-top:.25rem}.page-title{margin:.1rem 0 .5rem}.sudoku{gap:.55rem}.controls{gap:.5rem}.board{--chrome:24rem}}@media(prefers-reduced-motion:reduce){*{transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}@property --tw-blur{syntax:"*";inherits:false}@property --tw-brightness{syntax:"*";inherits:false}@property --tw-contrast{syntax:"*";inherits:false}@property --tw-grayscale{syntax:"*";inherits:false}@property --tw-hue-rotate{syntax:"*";inherits:false}@property --tw-invert{syntax:"*";inherits:false}@property --tw-opacity{syntax:"*";inherits:false}@property --tw-saturate{syntax:"*";inherits:false}@property --tw-sepia{syntax:"*";inherits:false}@property --tw-drop-shadow{syntax:"*";inherits:false}@property --tw-drop-shadow-color{syntax:"*";inherits:false}@property --tw-drop-shadow-alpha{syntax:"<percentage>";inherits:false;initial-value:100%}@property --tw-drop-shadow-size{syntax:"*";inherits:false}