:root{font-family:ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;font-size:16px;color:#233c35;background:#f3f2eb;color-scheme:light;--paper:#f3f2eb;--ink:#233c35;--muted:#637269;--forest:#254c41;--line:#24463928;--accent:#ad643e;--serif:"Iowan Old Style","Palatino Linotype",Palatino,Georgia,serif;font-synthesis:none}*{box-sizing:border-box}body{margin:0;min-width:280px;background:linear-gradient(112deg,#faf9f280,#f3f2eb)}button,select{font:inherit}button{cursor:pointer;touch-action:manipulation}button:disabled{cursor:default;opacity:.35}a{color:inherit;text-underline-offset:5px}button,a,select{-webkit-tap-highlight-color:transparent}button:focus-visible,a:focus-visible,select:focus-visible,[tabindex]:focus-visible{outline:3px solid #bc7249;outline-offset:5px}button:focus:not(:focus-visible){outline:none}[hidden]{display:none!important}.sr-only{position:absolute;width:1px;height:1px;padding:0;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}::selection{background:#dce7d4}.skip-link{position:fixed;left:14px;top:10px;padding:10px 15px;background:var(--forest);color:white;z-index:10;transform:translateY(-160%)}.skip-link:focus{transform:none}.site-header{max-width:1180px;margin:auto;padding:30px 52px 0;display:flex;justify-content:space-between;align-items:center;gap:20px}.brand{font-weight:750;font-size:25px;letter-spacing:-1.15px;text-decoration:none;display:flex;align-items:center;gap:10px}.brand-mark{width:23px;height:23px;display:grid;grid-template-columns:repeat(2,1fr);gap:3px;rotate:-5deg}.brand-mark i{background:var(--forest);border-radius:2px}.site-header>a:last-child{font-size:12px;text-decoration:none}.site-header>a:last-child span{margin-left:7px}main{max-width:822px;margin:0 auto;padding:51px 32px 0;outline:none!important}.game-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:28px;margin-bottom:25px}h1{font-size:43px;font-weight:600;line-height:1.1;letter-spacing:-2px;margin:0 0 11px}.game-heading p{font-size:13px;line-height:1.75;color:var(--muted);margin:0}.mobile-break{display:none}.size-picker{display:flex;flex-direction:column;gap:9px;font-size:10px;color:var(--muted);min-width:168px}.size-picker select{appearance:auto;background:transparent;color:var(--ink);font-size:12px;border:0;border-bottom:1px solid var(--line);border-radius:0;padding:8px 17px 8px 0;cursor:pointer;width:100%}.workspace{display:grid;grid-template-columns:minmax(0,1fr) 168px;gap:41px;align-items:start}.puzzle-column{min-width:0}.board-toolbar{display:flex;justify-content:space-between;align-items:center;margin-bottom:16px;gap:12px}.mode-switch{display:flex;gap:21px}.mode-switch button{border:0;border-bottom:2px solid transparent;padding:10px 0;background:transparent;font-size:12px;color:var(--muted)}.mode-switch button.selected{border-bottom-color:var(--forest);color:var(--ink);font-weight:600}.mode-switch button:hover{color:var(--ink)}#puzzle-date{font-size:10px;color:var(--muted);text-align:right;line-height:1.5}.board-frame{padding:17px;background:var(--forest);border:1px solid #23483d;border-radius:9px;box-shadow:0 10px 0 -5px #1e3f35,0 22px 30px -14px #173b3430,inset 0 1px 1px #799c845e}.board{position:relative;aspect-ratio:1;--size:3;outline-offset:9px!important}.tile,.gap{position:absolute;border-radius:6px}.tile{padding:0;border:1px solid #fdfaf0;background:linear-gradient(145deg,#f8f4e8,#eae6d9);color:var(--forest);font-family:var(--serif);font-size:clamp(36px,4.5vw,58px);font-weight:400;line-height:1;box-shadow:0 4px 0 #c7cbbd,0 5px 5px #142d2636,inset 0 1px 2px #fffefa;transition:left .17s cubic-bezier(.2,.7,.4,1),top .17s cubic-bezier(.2,.7,.4,1),background .15s,box-shadow .15s;z-index:1;opacity:1!important;cursor:default}.tile.is-movable{cursor:pointer;background:linear-gradient(145deg,#fffaf0,#f0eada)}.tile.is-movable:hover{background:#fffdf6;box-shadow:0 4px 0 #d7cdb9,0 7px 8px #142d264d}.tile.is-movable:active{box-shadow:0 2px 0 #c7cbbd,0 3px 5px #142d2636}.tile.is-hint{outline:3px solid #e8b16f;outline-offset:-7px}.tile.is-hint:after{content:"";position:absolute;width:6px;height:6px;border-radius:50%;background:var(--accent);bottom:13%;left:calc(50% - 3px)}.gap{border:1px dashed #93ad9866;background:#1c3d3324;transition:left .17s,top .17s;display:grid;place-items:center;color:#a5b8a882;font-family:var(--serif);font-size:24px}.gap:after{content:"·"}.board[data-size="4"] .tile{font-size:clamp(27px,3.5vw,44px)}.board-help{font-size:11px;text-align:center;line-height:1.75;color:var(--muted);margin:22px 0 0}.board-help br{display:none}.board-help br:after{content:" "}.board-help{white-space:normal}.game-rail{padding-top:57px}.moves{display:flex;flex-direction:column;gap:8px;border-bottom:1px solid var(--line);padding-bottom:25px}.moves span{font-size:12px;color:var(--muted)}.moves strong{font-size:50px;font-family:var(--serif);font-weight:400;line-height:1;font-variant-numeric:tabular-nums}.tools{display:flex;flex-direction:column;gap:4px;margin:16px 0 13px}.tools button{border:0;background:transparent;text-align:left;color:var(--ink);font-size:13px;min-height:39px;padding:7px 0}.tools button span{display:inline-block;min-width:28px;font-size:24px;line-height:1;vertical-align:-2px}.tools button:hover:not(:disabled){color:var(--accent)}.goal-example{border-top:1px solid var(--line);padding-top:14px;margin-top:5px}.goal-example summary{font-size:11px;color:var(--muted);cursor:pointer;padding:4px 0}.goal-board{display:grid;gap:3px;margin-top:13px;max-width:135px}.goal-board span{aspect-ratio:1;background:#e4e6da;display:grid;place-items:center;font-family:var(--serif);font-size:17px;border-radius:2px;color:#486552}.goal-board .empty{background:transparent;border:1px dashed #bec7b9}.goal-example p{font-size:10px;line-height:1.6;color:var(--muted);margin:10px 0 0}.text-button{font-size:11px;border:0;background:transparent;color:var(--accent);text-align:left;padding:15px 0 3px;line-height:1.6}.text-button span{margin-left:5px}.game-messages{margin-top:21px}.feedback{font-size:12px;line-height:1.7;color:var(--muted);margin:0;min-height:21px;max-width:640px}.feedback.hint-message{color:#8f5637}.victory{display:flex;align-items:center;justify-content:space-between;gap:30px;padding:21px 0 0;margin-top:18px;border-top:1px solid var(--line);animation:arrive .3s ease-out}.victory h2{font-family:var(--serif);font-size:28px;line-height:1.2;font-weight:400;letter-spacing:-.7px;margin:0 0 9px}.victory p{font-size:12px;line-height:1.7;color:var(--muted);margin:0}.primary-button{background:var(--forest);color:#faf9ef;font-size:12px;border:1px solid var(--forest);border-radius:5px;padding:13px 17px;line-height:1.5;white-space:nowrap}.primary-button:hover{background:#39614f}.primary-button span{margin-left:9px}.notice{border:1px solid #bca88283;border-radius:4px;background:#f7ecd9;padding:12px 15px;margin-top:15px;font-size:12px;line-height:1.7}.notice p{margin:0}.notice button{background:transparent;border:0;padding:7px 0 0;font-size:12px;color:#8f5637;text-decoration:underline;text-underline-offset:4px}.about{display:grid;grid-template-columns:.95fr 1.2fr;gap:35px;border-top:1px solid var(--line);margin-top:42px;padding:30px 0 34px}.about h2{font-family:var(--serif);font-weight:400;font-size:31px;line-height:1.25;letter-spacing:-.8px;margin:0;max-width:280px}.about p{font-size:12px;line-height:1.85;color:var(--muted);margin:0 0 13px}.about a{font-size:11px;text-decoration:none}.about a span{margin-left:8px}.site-footer{max-width:1076px;margin:0 auto;padding:25px 0 32px;border-top:1px solid var(--line);display:flex;justify-content:space-between;gap:25px;font-size:10px;color:var(--muted)}.site-footer>a{font-size:17px;font-weight:650;letter-spacing:-.7px;text-decoration:none;color:var(--ink)}.site-footer nav{display:flex;gap:25px}.site-footer nav a{text-decoration:none}dialog{background:var(--paper);color:var(--ink);border:1px solid #bac4b6;border-radius:8px;box-shadow:0 20px 90px #1b302942;padding:28px;width:calc(100% - 36px);max-width:430px}dialog::backdrop{background:#182b248c;backdrop-filter:blur(3px)}dialog h2{font-family:var(--serif);font-size:30px;line-height:1.2;font-weight:400;margin:0 0 16px;letter-spacing:-.5px}dialog p{font-size:13px;line-height:1.8;color:var(--muted);margin:0 0 25px}.dialog-actions{display:flex;justify-content:flex-end;gap:10px;flex-wrap:wrap}.dialog-actions button:not(.primary-button){background:transparent;border:1px solid #aebcad;color:var(--ink);border-radius:5px;padding:11px 15px;font-size:12px}@keyframes arrive{from{opacity:0;translate:0 5px}to{opacity:1;translate:0 0}}
.guide{max-width:800px;padding-top:58px}.guide-header{border-bottom:1px solid var(--line);padding-bottom:30px;margin-bottom:32px}.guide-header h1{font-size:43px;letter-spacing:-1.6px;max-width:600px;line-height:1.15}.guide-header>p{font-size:16px;line-height:1.8;color:var(--muted);max-width:590px;margin:18px 0 0}.guide section{max-width:650px;margin-bottom:35px}.guide h2{font-size:28px;font-family:var(--serif);font-weight:400;letter-spacing:-.5px;margin:0 0 15px}.guide p,.guide li{font-size:14px;line-height:1.9;color:var(--muted)}.guide strong{color:var(--ink);font-weight:550}.guide ol,.guide ul{padding-left:22px}.guide li{padding-left:5px;margin-bottom:9px}.guide .primary-button{display:inline-block;text-decoration:none;margin:8px 0 20px}.example-pair{display:flex;gap:25px;align-items:center;margin:23px 0}.example-board{display:grid;grid-template-columns:repeat(3,1fr);gap:4px;width:140px;background:var(--forest);padding:7px;border-radius:5px}.example-board span{aspect-ratio:1;display:grid;place-items:center;background:#f4efdf;color:var(--forest);border-radius:2px;font-family:var(--serif);font-size:23px}.example-board .empty{background:#1c3d3324;border:1px dashed #93ad9866}.example-board .marked{outline:2px solid #c9874b;outline-offset:-4px}.example-arrow{font-size:23px;color:var(--accent)}.example-caption{font-size:12px!important}.key{font-size:11px;line-height:1.5;background:#fff8;border:1px solid #b8c2b4;border-radius:3px;padding:2px 5px;color:var(--ink)}
@media(max-width:1180px){.site-footer{margin-left:52px;margin-right:52px}}@media(max-width:690px){.site-header{padding:24px 24px 0}.brand{font-size:23px}.site-header>a:last-child{font-size:11px}main{padding:33px 24px 0;max-width:520px}.game-heading{align-items:center;gap:14px;margin-bottom:15px}h1{font-size:35px;letter-spacing:-1.5px}.game-heading p{font-size:11px;line-height:1.65}.mobile-break{display:block}.size-picker{min-width:117px;font-size:12px;gap:5px}.size-picker select{font-size:13px;padding-right:0}.workspace{grid-template-columns:1fr;gap:20px}.board-toolbar{margin-bottom:13px}.mode-switch{gap:20px}.mode-switch button{font-size:12px}#puzzle-date{font-size:10px}.board-frame{padding:14px}.tile{font-size:55px}.board[data-size="4"] .tile{font-size:37px}.board-help{font-size:10px;margin-top:19px}.board-help br{display:block}.game-rail{padding-top:0;display:grid;grid-template-columns:75px 1fr;column-gap:15px;row-gap:9px;align-items:center}.moves{padding:0 15px 0 0;border:0;border-right:1px solid var(--line);gap:5px}.moves span{font-size:10px}.moves strong{font-size:35px}.tools{flex-direction:row;flex-wrap:wrap;justify-content:flex-start;gap:5px;margin:0}.tools button{font-size:13px;padding:7px 2px;min-height:40px}.tools button span{font-size:21px;min-width:21px}.goal-example{grid-column:1/-1;margin-top:6px;padding-top:10px}.goal-example summary{font-size:10px}.goal-board{max-width:120px}.text-button{grid-column:1/-1;text-align:center;padding:4px 0;font-size:11px}.game-messages{margin-top:17px}.feedback{font-size:11px;line-height:1.75}.victory{display:block;padding-top:18px;margin-top:14px}.victory h2{font-size:27px}.victory p{font-size:11px;margin-bottom:17px}.primary-button{font-size:11px}.about{grid-template-columns:1fr;gap:18px;margin-top:28px;padding:25px 0 30px}.about h2{font-size:29px;max-width:none}.about p{font-size:11px}.site-footer{margin-left:24px;margin-right:24px;padding:22px 0 27px}.site-footer nav{gap:20px}.guide{max-width:680px;padding-top:38px}.guide-header h1{font-size:36px}.guide-header>p{font-size:14px}.guide p,.guide li{font-size:13px}.guide h2{font-size:26px}.example-pair{gap:17px}.example-board{width:130px}}@media(max-width:350px){.site-header{padding-left:17px;padding-right:17px}main{padding-left:17px;padding-right:17px}h1{font-size:31px}.size-picker{min-width:111px}.board-frame{padding:11px}.tile{font-size:46px}.board[data-size="4"] .tile{font-size:31px}.tools button{font-size:13px}.tools button span{min-width:18px;font-size:20px}.game-rail{grid-template-columns:60px 1fr;gap:12px}.moves strong{font-size:32px}.example-board{width:118px}.example-pair{gap:12px}}@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}

.tools button,.mode-switch button,.size-picker select,.goal-example summary,.text-button,.primary-button,.notice button{min-height:44px;min-width:44px}.goal-example summary{display:flex;align-items:center}.site-header>a,.site-footer a,.about a{min-height:44px;display:inline-flex;align-items:center}.victory{margin-top:0;padding-top:18px}.victory h2{margin-bottom:14px}