:root{color-scheme:light;--page:#edf3f4;--ink:#2d4654;--muted:#58707b;--line:#c9d7d9;--paper:#fff9eb;--paper-edge:#dccdae;--purple:#ded9ed;--purple-ink:#50435f;--purple-edge:#b5a9d0;--action:#51425d;--teal:#315e64;--green:#b0dfbf;--green-ink:#24563e;--green-edge:#619576;--blue:#c3e5fa;--blue-edge:#649ab9;--yellow:#ffe180;--yellow-ink:#624c06;--red:#efada1;--red-ink:#702a23;--radius:18px;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;font-synthesis:none;scroll-behavior:smooth}
*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--page);font-size:16px;line-height:1.6}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;color:inherit;cursor:pointer;touch-action:manipulation}button:disabled{cursor:default;opacity:.42}button:focus-visible,a:focus-visible,summary:focus-visible,[tabindex]:focus-visible{outline:3px solid var(--teal);outline-offset:5px}a{color:inherit;text-underline-offset:4px}button,a,summary{touch-action:manipulation}button,[role=tab],summary{min-height:44px}h1,h2,h3,p{margin:0}h1,h2,h3{font-weight:750;line-height:1.15}h2{font-size:clamp(29px,3.1vw,39px);letter-spacing:-.045em}h3{font-size:20px;letter-spacing:-.025em}p{color:var(--muted)}[hidden]{display:none!important}section[id]{scroll-margin-top:24px}.page-shell{width:min(1120px,calc(100% - 80px));margin:auto}.skip-link{position:fixed;left:16px;top:-100px;background:var(--paper);padding:12px 18px;z-index:20}.skip-link:focus{top:12px}.site-header{min-height:100px;border-bottom:1px solid var(--line);display:flex;align-items:center;gap:28px}.brand{display:block;line-height:0}.brand img{width:200px;height:67px;object-fit:contain}.header-nav{display:flex;gap:28px;margin-left:auto;font-size:14px;font-weight:650}.header-nav a{text-decoration:none;padding:12px 0}.header-nav a:hover{text-decoration:underline}.language-toggle{border:1px solid var(--line);background:transparent;padding:8px 12px;border-radius:9px;font-size:12px;font-weight:600}.language-toggle span{margin-left:6px}.eyebrow{font-size:10px;letter-spacing:.14em;font-weight:800;color:var(--teal);display:flex;align-items:center;gap:8px;line-height:1.5}.eyebrow-dot{width:7px;height:7px;border-radius:50%;background:#719287}.intro{display:grid;grid-template-columns:1.07fr 1fr;align-items:center;gap:42px;padding:66px 0 60px;min-height:442px}.intro 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38px;background:var(--paper);border:1px solid var(--paper-edge);border-radius:12px;transform:rotate(-5deg);width:310px;box-shadow:0 5px 0 #dccdae70}.paper-clue p{font-size:23px;line-height:1.22;letter-spacing:-.025em;color:var(--ink);font-weight:650;margin-top:10px;white-space:pre-line}.mini-label{font-size:9px;letter-spacing:.13em;font-weight:800;color:var(--purple-ink)}.paper-corner{position:absolute;right:16px;top:16px;color:#bc8e4d;font-size:22px}.hero-letters{position:absolute;display:flex;gap:9px;left:34px;top:145px}.hero-cube{width:77px;height:79px;display:grid;place-items:center;border:1px solid var(--paper-edge);border-radius:15px;background:#fff3d8;box-shadow:0 6px 0 #c2b79e;font-size:44px;font-weight:800;position:relative;line-height:1}.hero-cube small{position:absolute;left:8px;top:8px;font-size:9px;font-weight:700;color:#81745f}.cube-r{transform:rotate(-8deg) translateY(9px)}.cube-o{transform:rotate(3deg) translateY(-5px);background:var(--blue);border-color:var(--blue-edge);box-shadow:0 6px 0 var(--blue-edge)}.cube-l1{transform:rotate(-4deg) translateY(3px)}.cube-l2{transform:rotate(9deg) translateY(-8px);background:var(--green);border-color:var(--green-edge);box-shadow:0 6px 0 var(--green-edge)}.illustration-track{position:absolute;display:flex;gap:10px;left:22px;top:159px;transform:rotate(-4deg);z-index:-1}.illustration-track span{width:70px;height:75px;border:1px solid #d0d6d1;border-radius:15px;background:#e3e8e3}.pencil-arrow{position:absolute;top:210px;left:38px;font-size:44px;color:#b78f56;transform:rotate(-22deg)}.illustration-caption{position:absolute;left:117px;top:258px;font-size:13px;font-style:italic;color:var(--muted);transform:rotate(-3deg)}.chapter-nav{display:grid;grid-template-columns:repeat(4,1fr);border-block:1px solid var(--line);padding:13px 0;gap:12px}.chapter-nav 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var(--line);font-size:11px;font-weight:700}.step-art{height:102px;display:flex;align-items:center;justify-content:center;margin-bottom:22px}.clue-art{flex-direction:column;font-size:16px;font-weight:750;gap:4px;letter-spacing:.04em}.clue-art small{font-size:16px}.clue-art b{display:inline-block;min-width:28px;text-align:center;color:var(--purple-ink);border-bottom:2px solid var(--purple-edge)}.rolling-art{gap:21px}.little-tile{width:56px;height:56px;background:var(--paper);border:1px solid var(--paper-edge);box-shadow:0 4px 0 #c6b89c;border-radius:11px;display:grid;place-items:center;font-size:28px;font-weight:750}.little-tile.selected{background:var(--blue);border-color:var(--blue-edge);box-shadow:0 4px 0 var(--blue-edge);transform:rotate(8deg)}.rolling-art b{font-size:30px;font-weight:400;color:var(--muted)}.answer-art{gap:5px;position:relative}.answer-art>span{width:40px;height:42px;background:var(--green);border:1px solid var(--green-edge);box-shadow:0 3px 0 var(--green-edge);border-radius:7px;display:grid;place-items:center;font-size:22px;font-weight:750;color:var(--green-ink)}.answer-art>small{font-size:16px;color:var(--green-ink);margin-left:4px}.basics-grid h3{margin-bottom:10px}.basics-grid p{font-size:14px;line-height:1.7;max-width:302px}.practice-section{display:grid;grid-template-columns:.86fr 1.14fr;gap:55px;padding:50px;background:#e2ebe9;border:1px solid #d0ddda;border-radius:24px;align-items:start}.practice-copy h2{margin:15px 0 20px;font-size:36px;white-space:pre-line}.practice-copy>p:not(.eyebrow){font-size:14px;line-height:1.75}.practice-steps{padding:0;margin:26px 0;list-style:none;display:grid;gap:17px}.practice-steps li{display:flex;gap:12px;align-items:flex-start}.practice-steps li>span{flex:0 0 23px;height:23px;border:1px solid #9fb6b0;border-radius:50%;display:grid;place-items:center;font-size:10px;font-weight:750}.practice-steps p{font-size:13px;line-height:1.65;color:var(--ink)}.practice-note{border-top:1px solid #c5d5cf;padding-top:16px;display:flex;gap:12px;color:var(--muted);font-size:12px;line-height:1.6}.practice-note>span:first-child{font-size:24px;color:#7b958c}.practice-lab{border:1px solid #c6d6d1;border-radius:18px;background:#f7faf7;box-shadow:0 5px 0 #bfceca;min-width:0;padding:22px}.lab-header{display:flex;justify-content:space-between;align-items:center;gap:12px;border-bottom:1px solid #d9e3de;padding-bottom:15px}.lab-label{display:flex;align-items:center;gap:7px;font-size:9px;letter-spacing:.08em;font-weight:800}.status-dot{width:6px;height:6px;background:#729587;border-radius:50%}.roll-count{display:flex;align-items:center;gap:10px;font-size:9px;letter-spacing:.08em;font-weight:700}.roll-count strong{font-size:23px;line-height:1;font-variant-numeric:tabular-nums;color:var(--teal)}.lab-topline{display:flex;align-items:center;gap:22px;padding:20px 0 21px;justify-content:center}.face-net{display:grid;grid-template-columns:repeat(4,25px);grid-template-rows:repeat(3,25px);gap:3px}.face-net span{display:grid;place-items:center;border:1px solid #d4dddc;background:#eef3f3;border-radius:5px;font-size:15px;line-height:1;font-weight:700}.face-net [data-face=north]{grid-area:1/2}.face-net [data-face=west]{grid-area:2/1}.face-net [data-face=top]{grid-area:2/2;background:var(--blue);border-color:var(--blue-edge)}.face-net [data-face=east]{grid-area:2/3}.face-net [data-face=bottom]{grid-area:2/4}.face-net [data-face=south]{grid-area:3/2}.net-caption{display:grid;gap:3px;font-size:11px;max-width:144px;line-height:1.5}.net-caption span{color:var(--muted)}.net-caption 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var(--blue-edge);border-radius:10px;display:grid;place-items:center;outline:2px solid var(--purple-ink);outline-offset:2px;pointer-events:none}.lesson-cube>strong{font-size:29px;line-height:1}.lesson-cube>small{position:absolute;top:3px;left:5px;font-size:8px;font-weight:750;line-height:1}.lesson-cube .lock-mark{display:none;position:absolute;bottom:3px;right:4px;font-size:10px;line-height:1}.lesson-cube.solved{background:var(--green);border-color:var(--green-edge);color:var(--green-ink);box-shadow:0 4px 0 var(--green-edge);outline:none}.lesson-cube.solved .lock-mark{display:block}.lesson-cube.wrong{background:var(--red);border-color:#b3675b;color:var(--red-ink);box-shadow:0 4px 0 #b3675b}.lesson-cube.just-rolled{animation:roll-pop .18s ease-out}.direction-area{display:grid;gap:12px;justify-items:center}.direction-pad{display:grid;grid-template-columns:repeat(3,39px);grid-template-rows:repeat(3,42px);gap:3px}.direction-pad button{background:#edf1eb;border:1px solid #cbd7ce;border-radius:9px;box-shadow:0 2px 0 #c6d2c9;font-size:23px;line-height:1;padding:0;min-height:42px}.direction-pad button:not(:disabled):hover{background:var(--blue)}.direction-pad button:not(:disabled):active{transform:translateY(2px);box-shadow:none}.direction-pad [data-roll=N]{grid-area:1/2}.direction-pad [data-roll=W]{grid-area:2/1}.direction-pad [data-roll=E]{grid-area:2/3}.direction-pad [data-roll=S]{grid-area:3/2}.pad-center{grid-area:2/2;display:grid;place-items:center;font-weight:800;background:var(--paper);border:1px solid var(--paper-edge);border-radius:8px;font-size:20px}.keyboard-note{font-size:9px;color:var(--muted);line-height:1.3;max-width:100px;text-align:center}.lab-message{margin-top:24px;min-height:70px;background:#ebe7f2;border:1px solid #dcd4e6;padding:10px 13px;border-radius:9px;font-size:12px;line-height:1.5;display:grid;align-content:center;gap:2px;color:var(--purple-ink)}.lab-message strong{font-size:13px}.lab-message[data-status=won]{background:#e1efdf;border-color:#abc4ae;color:var(--green-ink)}.lab-actions{display:flex;gap:10px;align-items:center;margin-top:15px;flex-wrap:wrap}.lab-actions .button{min-height:44px;padding:9px 13px;font-size:12px;gap:8px}.button.subtle{background:transparent;border-color:#c8d5cc;box-shadow:0 2px 0 #d3ddd6}.text-button{border:0;background:transparent;padding:10px 0;font-size:11px;text-decoration:underline;text-underline-offset:3px;margin-left:auto}.noscript-note{margin-top:20px;font-size:13px}.feedback-section{border-bottom:1px solid var(--line)}.feedback-heading{display:flex;justify-content:space-between;align-items:baseline;gap:25px;margin-bottom:30px}.feedback-heading h2{font-size:26px;letter-spacing:-.03em}.feedback-heading p{font-size:12px}.feedback-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}.feedback-grid article{display:grid;grid-template-columns:45px 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var(--line);padding-bottom:14px}.clue-tabs button{background:transparent;border:1px solid transparent;padding:9px 17px;border-radius:9px;font-size:13px;font-weight:650;white-space:nowrap}.clue-tabs button[aria-selected=true]{background:var(--purple);border-color:var(--purple-edge);color:var(--purple-ink);box-shadow:0 2px 0 #b5abc8}.clue-tabs button:hover{border-color:var(--purple-edge)}.clue-panel{display:grid;grid-template-columns:1.1fr 1fr;gap:60px;padding-top:9px;align-items:center}.clue-panel+.clue-panel{margin-top:30px}.clue-panel[role=tabpanel]{margin-top:0}.example-paper{position:relative;background:var(--paper);border:1px solid var(--paper-edge);border-radius:15px;padding:28px 30px;box-shadow:0 4px 0 #d8d0bb;min-height:258px}.example-clue{font-size:28px;color:var(--ink);font-weight:750;letter-spacing:-.035em;margin:18px 0 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var(--line);display:grid;grid-template-columns:1fr 1fr;gap:80px}.tools-section h2{margin:13px 0 19px;white-space:pre-line}.tools-section>div>p:not(.eyebrow){font-size:14px;line-height:1.7;max-width:360px}.tools-list{display:grid;gap:22px}.tools-list article{display:flex;gap:20px}.tools-list article>img{opacity:.72;flex-shrink:0;margin-top:2px}.tools-list h3{font-size:17px;margin-bottom:7px}.tools-list p{font-size:13px;line-height:1.7}.tool-symbol{width:26px;flex:0 0 26px;font-size:29px;font-weight:500;line-height:1.1;text-align:center;color:var(--purple-ink)}.weekly-section{padding:46px 48px;display:grid;grid-template-columns:1.1fr 1fr;gap:50px;background:#e5e0ef;border:1px solid #cfc5de;border-radius:24px;align-items:center}.weekly-copy .eyebrow{color:var(--purple-ink)}.weekly-copy h2{font-size:36px;margin:15px 0 20px;color:var(--purple-ink);white-space:pre-line}.weekly-copy>p:not(.eyebrow){font-size:14px;line-height:1.75;color:#5e566b}.weekly-rules{padding-left:18px;margin:22px 0 0;font-size:12px;color:#5e566b;line-height:1.75;display:grid;gap:10px}.weekly-rules li{padding-left:4px}.weekly-rules li::marker{color:#9b89b0}.weekly-illustration{min-width:0}.week-days{display:flex;gap:6px;justify-content:center}.week-days>span{width:37px;height:52px;display:grid;justify-items:center;align-content:center;gap:4px;font-size:10px;font-weight:700;border:1px solid #c6bbd4;border-radius:8px;background:#f0ebf5;color:#887993}.week-days>span:nth-child(-n+3){background:#eef4e9;color:var(--green-ink);border-color:#99b9a2}.week-days small{font-size:13px;line-height:1}.fragment-path{display:flex;justify-content:center;gap:55px;font-size:28px;font-weight:300;color:#ad9cbf;height:45px;align-items:center}.fragment-pool{display:flex;gap:8px;justify-content:center}.fragment-pool span{width:40px;height:41px;display:grid;place-items:center;background:var(--paper);border:1px solid var(--paper-edge);border-radius:8px;box-shadow:0 3px 0 #b4ac9d;font-weight:750;font-size:20px}.fragment-pool span:nth-child(2n){transform:rotate(5deg)}.fragment-pool span:nth-child(2n+1){transform:rotate(-4deg)}.weekly-paper{max-width:280px;margin:27px auto 0;background:#f5f2f8;border:1px solid #c5b9d8;border-radius:14px;padding:20px 22px 24px;box-shadow:0 4px 0 #c2b8cf;transform:rotate(-3deg)}.weekly-paper .mini-label{display:block;margin-bottom:12px;text-align:center}.phrase-row{display:flex;gap:6px;justify-content:center;margin:8px 0}.phrase-row span{width:31px;height:31px;display:grid;place-items:center;background:var(--green);border:1px solid var(--green-edge);border-radius:5px;font-size:16px;line-height:1;font-weight:750;color:var(--green-ink);box-shadow:0 2px 0 var(--green-edge)}.phrase-row.empty span{background:#e6e0ee;border-color:#c3b8d1;box-shadow:0 2px 0 #c3b8d1}.illustration-only{font-size:10px;color:#6d617a;text-align:center;margin:22px auto 0;max-width:275px;line-height:1.6}.faq-section{display:grid;grid-template-columns:.65fr 1.35fr;gap:70px}.faq-section h2{margin-top:14px}.faq-list details{border-bottom:1px solid var(--line)}.faq-list details:first-child{border-top:1px solid var(--line)}.faq-list summary{font-size:14px;font-weight:650;padding:19px 35px 19px 0;cursor:pointer;list-style:none;position:relative;line-height:1.5}.faq-list summary::-webkit-details-marker{display:none}.faq-list summary::after{content:'+';position:absolute;right:2px;top:15px;font-size:24px;font-weight:400;color:#71878d}.faq-list details[open] summary::after{content:'−'}.faq-list details p{font-size:13px;line-height:1.8;padding:0 28px 20px 0}.closing{border-top:1px solid var(--line);padding:37px 0 43px;display:flex;justify-content:space-between;align-items:center;gap:30px}.closing h2{margin-top:12px;font-size:31px;white-space:pre-line}.closing .button{min-width:225px}.site-footer{display:grid;grid-template-columns:auto 1fr auto;gap:24px;border-top:1px solid var(--line);padding:23px 0 28px;align-items:start;font-size:10px;color:var(--muted)}.site-footer>span{font-weight:650}.site-footer>span>span:first-child{margin:0 5px;color:#ba9758}.site-footer p{max-width:290px;justify-self:center;font-size:10px;line-height:1.6}.site-footer a{text-decoration:none;white-space:nowrap}html[lang=zh-CN] h1{font-size:52px;line-height:1.18;letter-spacing:-.025em}html[lang=zh-CN] h2{line-height:1.3;letter-spacing:-.025em}html[lang=zh-CN] .intro-description{line-height:1.85}html[lang=zh-CN] .small-note{max-width:130px}html[lang=zh-CN] .example-clue.smaller{line-height:1.65}
@keyframes roll-pop{0%{transform:translateY(-3px) scale(.97)}100%{transform:translateY(0) scale(1)}}
@media(min-width:1400px){.intro{padding-block:75px}.intro h1{font-size:67px}}
@media(max-width:1050px){.page-shell{width:calc(100% - 56px)}.intro{gap:25px}.intro-illustration{transform:scale(.9);transform-origin:center}.intro-actions{gap:12px}.practice-section{padding:32px;gap:30px;grid-template-columns:.8fr 1.2fr}.practice-copy h2{font-size:30px}.practice-lab{padding:18px}.board-and-controls{gap:16px}.lesson-board{grid-template-columns:repeat(3,48px);grid-template-rows:repeat(3,48px);gap:5px}.direction-pad{grid-template-columns:repeat(3,35px);grid-template-rows:repeat(3,42px)}.header-nav{gap:18px}.clue-panel{gap:40px}.feedback-grid{gap:18px}.feedback-grid article{display:block}.feedback-grid h3{margin:16px 0 6px}.weekly-section{padding:35px;gap:30px}.weekly-copy h2{font-size:32px}.tools-section{gap:50px}}
@media(max-width:800px){.page-shell{width:calc(100% - 40px)}.site-header{min-height:82px;gap:14px}.brand img{width:168px;height:56px}.header-nav{margin-left:auto}.header-nav a{font-size:12px}.header-nav a:last-child{display:none}.language-toggle{font-size:11px;padding-inline:10px}.intro{gap:6px;padding:45px 0;grid-template-columns:1fr .88fr;min-height:375px}.intro h1{font-size:48px}.intro-description{font-size:15px}.intro-illustration{transform:scale(.77);transform-origin:left center;margin-right:-60px}.intro-actions{flex-wrap:wrap}.small-note{max-width:none}.section{padding:45px 0}.section-heading{margin-bottom:26px}.section-heading>p{font-size:11px;max-width:165px}.basics-grid{gap:24px}.basics-grid p{font-size:13px}.basics-grid h3{font-size:18px}.practice-section{grid-template-columns:1fr;gap:27px;padding:32px;max-width:650px;margin:auto}.practice-copy h2 br{display:none}.practice-copy h2{white-space:normal;font-size:32px}.practice-steps{margin:20px 0;gap:12px}.practice-lab{padding:23px;max-width:480px;width:100%;justify-self:center}.lesson-board{grid-template-columns:repeat(3,62px);grid-template-rows:repeat(3,62px);gap:6px}.direction-pad{grid-template-columns:repeat(3,43px);grid-template-rows:repeat(3,44px);gap:3px}.direction-pad button{min-height:44px}.board-and-controls{gap:30px}.lab-actions{justify-content:center}.text-button{margin-left:10px}.lab-message{min-height:66px}.feedback-heading{display:block}.feedback-heading p{margin-top:10px}.clue-tabs button{padding-inline:13px}.example-paper{padding:24px 22px}.example-clue{font-size:23px}.example-clue.smaller{font-size:20px}.clue-panel{gap:30px}.example-explainer h3{font-size:22px}.tools-section{gap:35px}.tools-section h2{font-size:30px}.weekly-section{grid-template-columns:1fr;gap:36px;padding:35px}.weekly-copy h2{font-size:34px}.weekly-illustration{max-width:350px;width:100%;justify-self:center}.faq-section{grid-template-columns:.6fr 1.4fr;gap:30px}.site-footer{grid-template-columns:1fr auto;gap:12px}.site-footer p{grid-row:2;grid-column:1/-1;justify-self:start;max-width:none}.site-footer a{grid-row:1;grid-column:2}html[lang=zh-CN] h1{font-size:40px}}
@media(max-width:600px){.page-shell{width:calc(100% - 36px)}.site-header{min-height:75px}.brand img{width:151px;height:51px}.header-nav{display:none}.language-toggle{margin-left:auto}.intro{display:block;padding:35px 0 25px;min-height:0}.intro-copy{position:relative;z-index:2}.intro h1{font-size:47px;line-height:1.03;margin:17px 0 19px}.intro-description{max-width:390px;font-size:15px;line-height:1.75}.intro-actions{margin-top:22px;gap:14px}.intro-actions .button{min-height:48px;padding-inline:18px;font-size:13px}.small-note{font-size:10px;max-width:125px}.intro-illustration{height:256px;min-height:0;transform:scale(.8);transform-origin:top center;width:400px;max-width:none;left:50%;margin-left:-200px;margin-right:0;margin-top:30px;margin-bottom:-35px}.paper-clue{left:36px;top:0}.hero-letters{left:35px}.illustration-caption{top:252px}.chapter-nav{grid-template-columns:1fr 1fr;gap:0 20px;padding-block:8px}.chapter-nav a{font-size:12px;gap:11px;min-height:44px}.section{padding:38px 0}.section-heading{display:block;margin-bottom:22px}.section-heading .eyebrow{margin-bottom:11px}.section-heading>p{margin-top:13px;max-width:270px;font-size:12px}.section-heading>p br{display:none}h2{font-size:29px;line-height:1.2}.basics-grid{display:block}.basics-grid li{display:grid;grid-template-columns:86px 1fr;gap:8px 15px;position:relative;padding:20px 0;border-bottom:1px solid var(--line)}.basics-grid li:last-child{border-bottom:0;padding-bottom:0}.step-number{top:23px;left:0;width:19px;height:19px;font-size:9px;background:var(--page);z-index:1}.step-art{grid-row:span 2;width:84px;height:70px;margin:15px 0 0;align-self:center}.clue-art{font-size:10px;gap:4px}.clue-art small{font-size:10px}.rolling-art{gap:7px}.little-tile{width:31px;height:33px;font-size:20px;border-radius:7px}.rolling-art b{font-size:17px}.answer-art{gap:3px;flex-wrap:wrap;align-content:center;padding:8px 6px}.answer-art>span{width:28px;height:30px;font-size:16px;border-radius:5px}.answer-art>small{display:none}.basics-grid h3{font-size:18px;align-self:end;margin-bottom:0}.basics-grid p{font-size:13px;line-height:1.65;max-width:none}.practice-section{border-radius:18px;padding:24px 16px 18px;gap:25px;margin-top:0}.practice-copy{padding:0 6px}.practice-copy h2{font-size:30px;margin-top:12px}.practice-copy>p:not(.eyebrow){font-size:13px}.practice-steps p{font-size:12px}.practice-note{font-size:11px}.practice-lab{padding:16px 13px;border-radius:14px}.lab-topline{gap:18px;padding-block:19px}.face-net{grid-template-columns:repeat(4,23px);grid-template-rows:repeat(3,23px)}.net-caption{font-size:10px;max-width:125px}.net-caption strong{font-size:11px}.board-and-controls{flex-direction:column;gap:19px}.lesson-board{grid-template-columns:repeat(3,62px);grid-template-rows:repeat(3,62px);gap:6px}.direction-area{display:flex;gap:16px;align-items:center}.direction-pad{grid-template-columns:repeat(3,44px);grid-template-rows:repeat(3,44px);gap:5px}.keyboard-note{font-size:10px;max-width:68px;text-align:left}.lab-message{margin-top:20px;font-size:11px;min-height:71px;padding-inline:11px}.lab-message strong{font-size:12px}.lab-actions{gap:9px;justify-content:space-between;margin-top:14px}.lab-actions .button{padding:9px 11px;font-size:11px;gap:6px}.text-button{font-size:10px;margin-left:0}.feedback-heading h2{font-size:25px}.feedback-heading p{font-size:11px}.feedback-grid{grid-template-columns:1fr 1fr;gap:25px 23px}.feedback-grid article{display:grid;grid-template-columns:37px 1fr;column-gap:10px;align-items:start}.state-tile{width:35px;height:38px;font-size:21px;grid-row:span 2}.feedback-grid h3{font-size:12px;line-height:1.4;margin:0}.feedback-grid p{font-size:11px;line-height:1.6;grid-column:2;margin-top:3px}.clue-tabs{display:grid;grid-template-columns:1fr 1fr;gap:6px;padding-bottom:15px}.clue-tabs button{font-size:12px;padding:9px 8px;white-space:normal}.clue-panel{display:flex;flex-direction:column;gap:25px;align-items:stretch}.example-paper{padding:22px;min-height:243px}.example-clue{font-size:26px;margin:16px 0 12px}.example-clue.smaller{font-size:22px}.example-explainer{padding:0 4px}.example-explainer h3{font-size:24px;max-width:none;margin:9px 0 12px}.example-explainer p{font-size:13px;max-width:none}.tip{margin-top:15px}.tools-section{grid-template-columns:1fr;gap:29px}.tools-section h2{font-size:30px}.tools-section>div>p:not(.eyebrow){font-size:13px}.tools-list{gap:23px}.tools-list article{gap:16px}.tools-list p{font-size:12px}.weekly-section{padding:28px 23px;border-radius:18px;gap:28px}.weekly-copy h2{font-size:30px;margin:13px 0 17px}.weekly-copy>p:not(.eyebrow){font-size:13px}.weekly-rules{font-size:12px;padding-left:15px;margin-top:18px;gap:11px}.week-days{gap:5px}.week-days>span{width:31px;height:49px}.fragment-pool{gap:6px}.fragment-pool span{width:35px;height:36px;font-size:19px}.weekly-paper{max-width:253px}.illustration-only{font-size:9px;max-width:240px}.faq-section{display:block}.faq-list{margin-top:25px}.faq-list summary{font-size:13px;padding-block:17px}.faq-list details p{font-size:12px}.closing{padding:29px 0 35px;display:block}.closing h2{font-size:29px}.closing .button{margin-top:23px;font-size:13px;min-width:0}.site-footer{font-size:9px;gap:12px 8px;padding-block:19px}.site-footer p{font-size:9px}html[lang=zh-CN] h1{font-size:40px;line-height:1.25}html[lang=zh-CN] .intro-illustration{margin-top:26px}html[lang=zh-CN] .intro-actions{gap:12px}html[lang=zh-CN] .small-note{max-width:115px}}
@media(max-width:360px){.page-shell{width:calc(100% - 28px)}.intro h1{font-size:43px}.intro-illustration{transform:scale(.73);margin-bottom:-57px}.practice-section{padding-inline:12px}.practice-lab{padding-inline:11px}.lesson-board{grid-template-columns:repeat(3,58px);grid-template-rows:repeat(3,58px)}.lab-actions{gap:6px}.lab-actions .button{padding-inline:9px;font-size:10px}.feedback-grid{gap:22px 14px}.feedback-grid article{display:block}.feedback-grid h3{margin-top:13px}.weekly-section{padding-inline:18px}.week-days{gap:4px}.week-days>span{width:29px}.site-footer>span>span:last-child{display:none}html[lang=zh-CN] h1{font-size:36px}}
/* Keep the underlying cells fixed while the independently positioned cube moves. */
.skip-link:not(:focus){clip-path:inset(50%);width:1px;height:1px;padding:0;overflow:hidden;white-space:nowrap}
summary{-webkit-tap-highlight-color:transparent}
.board-cell:nth-child(3n+1){grid-column:1}.board-cell:nth-child(3n+2){grid-column:2}.board-cell:nth-child(3n){grid-column:3}
.board-cell:nth-child(-n+3){grid-row:1}.board-cell:nth-child(n+4):nth-child(-n+6){grid-row:2}.board-cell:nth-child(n+7):nth-child(-n+9){grid-row:3}
.direction-pad{grid-template-columns:repeat(3,44px);grid-template-rows:repeat(3,44px)}.direction-pad button{min-height:44px}
[data-practice-lab][data-status=won] [data-face=top],[data-practice-lab][data-status=won] .pad-center{background:var(--green);border-color:var(--green-edge);color:var(--green-ink)}
[data-practice-lab][data-status=wrong] [data-face=top],[data-practice-lab][data-status=wrong] .pad-center{background:var(--red);border-color:#b3675b;color:var(--red-ink)}
@media(min-width:801px) and (max-width:1050px){.intro-illustration{transform:scale(.78);transform-origin:left center}}
@media(prefers-reduced-motion:reduce){:root{scroll-behavior:auto}*,*::before,*::after{animation:none!important;transition:none!important}}