/* Layer scale: content 0, sticky navigation 20, mobile navigation 21. */
:root{color-scheme:light;--page:#fffcf5;--surface:#fffefa;--ink:#202e50;--muted:#5b6985;--blue:#4266d8;--blue-soft:#edf2ff;--yellow:#ffd449;--yellow-soft:#fff4bf;--line:#dce2eb;--white:#fffefa;--shadow:0 20px 55px #24335c12;--radius:28px;--font:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif}
:root[data-theme=dark]{color-scheme:dark;--page:#171d2c;--surface:#20283a;--ink:#f0f2fb;--muted:#bac4dc;--blue:#a5baff;--blue-soft:#293750;--yellow-soft:#403c28;--line:#3c475e;--white:#20283a;--shadow:0 20px 55px #090e1b44}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:110px}body{margin:0;background:var(--page);color:var(--ink);font-family:var(--font);font-size:16px;line-height:1.7;-webkit-font-smoothing:antialiased}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;color:inherit;cursor:pointer}a{color:inherit;text-decoration:none}button,a,summary{touch-action:manipulation}a:hover{color:var(--blue)}button:focus-visible,a:focus-visible,summary:focus-visible,[tabindex="0"]:focus-visible{outline:3px solid var(--blue);outline-offset:5px}img{max-width:100%;display:block;height:auto}figure,p{margin:0}h1,h2,h3{margin:0;font-weight:700;line-height:1.3;letter-spacing:-.04em}h2{font-size:clamp(30px,3.1vw,44px)}h3{font-size:26px}p{color:var(--muted)}[hidden]{display:none!important}.container{width:min(1200px,calc(100% - 96px));margin-inline:auto}.icon{width:22px;height:22px;display:inline-block;flex:0 0 auto;vertical-align:middle;fill:currentColor}.skip-link{position:fixed;top:10px;left:20px;z-index:30;background:var(--ink);color:var(--page);padding:10px 18px;transform:translateY(-150%)}.skip-link:focus{transform:translateY(0)}
.site-header{height:82px;position:sticky;top:0;z-index:20;background:var(--page);border-bottom:1px solid var(--line)}.nav-shell{height:100%;display:flex;align-items:center;gap:28px}.brand{display:inline-flex;align-items:center;gap:12px;white-space:nowrap}.brand img{width:44px;height:44px}.brand-name{font-size:25px;font-weight:750;letter-spacing:.06em}.brand-en{display:block;font-size:9px;line-height:1;letter-spacing:.22em;color:var(--muted);font-weight:600;margin-top:4px}.navigation{display:flex;align-items:center;gap:30px;margin-left:auto;font-size:14px;font-weight:600}.nav-tools{display:flex;gap:14px;align-items:center}.icon-button{width:40px;height:40px;display:grid;place-items:center;background:none;border:1px solid var(--line);border-radius:50%}.icon-button:hover{background:var(--blue-soft)}[data-theme=dark] .theme-moon,[data-theme=light] .theme-sun{display:none}.menu-button{display:none}.button{display:inline-flex;align-items:center;justify-content:center;gap:15px;min-height:54px;padding:14px 24px;border-radius:14px;white-space:nowrap;font-size:15px;line-height:1.4;font-weight:650;border:1px solid transparent;transition:transform .2s,background-color .2s}.button:hover{transform:translateY(-2px)}.button.primary{background:var(--yellow);color:#202e50}.button.primary:hover{background:#ffdc6a}.button.secondary{background:var(--surface);border-color:var(--line);color:var(--ink)}.button.small{min-height:40px;font-size:13px;padding:10px 19px;border-radius:11px}.text-link{font-size:15px;display:inline-flex;align-items:center;gap:10px;font-weight:650}.text-link .icon{width:18px}.actions{display:flex;gap:28px;align-items:center;margin-top:34px}.eyebrow{font-size:13px;letter-spacing:.15em;color:var(--blue);font-weight:650;margin-bottom:20px}
.hero{display:grid;grid-template-columns:1fr 1fr;align-items:center;min-height:650px;padding-block:48px 36px;gap:30px}.hero-copy{padding-bottom:24px}.hero h1{font-size:clamp(38px,4vw,56px);line-height:1.42;letter-spacing:-.045em}.hero h1 span{color:var(--blue)}.hero-description{font-size:18px;margin-top:24px;line-height:1.9}.hero-visual{position:relative;height:554px;isolation:isolate;display:flex;align-items:center;justify-content:center}.hero-shape{position:absolute;inset:75px -8px 6px 18px;border-radius:48% 48% 35% 35%;background:var(--yellow-soft);z-index:-1}.phone{background:var(--surface);border:6px solid var(--surface);border-radius:30px;overflow:hidden;box-shadow:0 24px 64px #27396226}.phone img{width:100%;height:100%;object-fit:cover;border-radius:23px}.phone-home{position:absolute;width:244px;transform:rotate(-7deg);left:22px;top:10px;aspect-ratio:390/844}.phone-card{position:absolute;width:224px;transform:rotate(7deg);right:14px;bottom:0;aspect-ratio:390/844}.learning-path{display:flex;justify-content:space-between;align-items:center;padding:28px 20px;border-block:1px solid var(--line);gap:18px}.learning-path a{display:flex;align-items:center;justify-content:center;gap:14px;font-size:15px;font-weight:650}.learning-path a>.icon{width:28px;height:28px;color:var(--blue)}.path-arrow{color:var(--muted);opacity:.5}.path-arrow .icon{width:19px}
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.resource-section{padding-top:20px;padding-bottom:80px}.resource-grid{display:grid;grid-template-columns:1.35fr 1fr;gap:22px}.resource-example{border-radius:var(--radius);padding:36px;min-height:310px;overflow:hidden;position:relative}.resource-example h3{font-size:25px;margin:10px 0 16px}.resource-example p{font-size:14px;line-height:1.9}.small-label{font-size:11px;font-weight:600;color:var(--muted)}.math-resource{display:flex;align-items:center;background:var(--yellow-soft)}.math-resource>div{max-width:58%;position:relative;z-index:1}.math-resource img{width:260px;height:260px;object-fit:contain;position:absolute;right:-10px;bottom:10px}.resource-facts{display:block;font-size:11px;color:var(--muted);margin-top:28px}.methods-resource{background:var(--blue-soft)}.methods-resource p{max-width:330px}.word-stack{display:flex;gap:10px;margin-top:24px;transform:rotate(-4deg)}.word-stack span{background:var(--surface);border:1px solid var(--line);padding:10px 22px;border-radius:10px;color:var(--blue);font-size:17px;font-weight:650;box-shadow:0 5px 15px #26365608}.word-stack span:nth-child(2){transform:rotate(7deg) translateY(5px);background:var(--yellow);color:#202e50}.resource-footnote{font-size:12px;display:flex;gap:10px;align-items:center;margin-top:22px}.resource-footnote .icon{width:17px;height:17px}
.creation-layout{display:grid;grid-template-columns:1.05fr 1fr;gap:95px;align-items:center}.creation-copy>p:not(.eyebrow){margin-top:22px;font-size:15px;line-height:1.9}.creation-steps{list-style:none;margin:32px 0;padding:0;display:grid;gap:22px;counter-reset:step}.creation-steps li{position:relative;padding-left:40px;counter-increment:step}.creation-steps li:before{content:counter(step);position:absolute;left:0;top:2px;border:1px solid var(--line);border-radius:50%;width:26px;height:26px;display:grid;place-items:center;font-size:11px;color:var(--blue)}.creation-steps strong{display:block;font-size:15px}.creation-steps span{font-size:13px;color:var(--muted)}.creation-copy .subtle-note{font-size:12px!important}.editor-figure{background:var(--yellow-soft);padding:35px 42px 20px;border-radius:var(--radius);text-align:center;height:620px;overflow:hidden;position:relative}.editor-figure img{max-width:285px;margin:auto;border:4px solid var(--surface);border-radius:18px;box-shadow:var(--shadow)}.editor-figure figcaption{position:absolute;bottom:0;left:0;width:100%;padding:14px 12px;background:var(--yellow-soft);margin:0}.local-layout{display:grid;grid-template-columns:1.1fr 1fr;gap:75px;align-items:center}.learning-illustration{border-radius:var(--radius);overflow:hidden}.local-copy>p{font-size:15px;margin-top:22px}.local-points{list-style:none;padding:0;margin:26px 0;display:grid;gap:22px}.local-points li{display:flex;gap:16px}.local-points .icon{width:25px;height:25px;color:var(--blue);margin-top:3px}.local-points h3{font-size:16px;letter-spacing:0}.local-points p{font-size:13px;margin-top:6px}.faq-layout{display:grid;grid-template-columns:.85fr 1.15fr;gap:85px}.faq-layout h2{line-height:1.5;margin-bottom:24px}.faq-list details{border-bottom:1px solid var(--line);padding-block:20px}.faq-list details:first-child{padding-top:0}.faq-list summary{display:flex;align-items:center;justify-content:space-between;gap:20px;list-style:none;cursor:pointer;font-size:15px;font-weight:650;line-height:1.7}.faq-list summary::-webkit-details-marker{display:none}.faq-list summary .icon{width:18px;height:18px;transition:transform .2s}.faq-list details[open] summary .icon{transform:rotate(45deg)}.faq-list details p{margin-top:16px;font-size:13px;line-height:1.9;max-width:570px}
#download{padding-top:50px}.download-surface{padding:50px 50px 35px;background:var(--yellow-soft);border-radius:32px}.download-mark{margin:0 auto 20px}.download-grid{display:grid;grid-template-columns:1fr 1fr;gap:24px}.download-option{background:var(--surface);border:1px solid var(--line);border-radius:20px;padding:30px}.download-platform{display:flex;gap:12px;align-items:center}.download-platform>.icon{width:26px;height:26px;color:var(--blue)}.download-platform h3{font-size:21px}.download-option>p{font-size:13px;margin-top:14px}.download-option .button{width:100%;margin-top:24px;font-size:14px}.download-option .download-meta{font-size:11px;letter-spacing:.02em}.download-option .download-note{font-size:11px;margin-top:6px}.download-links{display:flex;gap:18px;margin-top:14px;font-size:11px}.download-links a{text-decoration:underline;text-underline-offset:4px}.release-note{text-align:center;font-size:11px;margin-top:26px}.release-note a{text-decoration:underline;text-underline-offset:4px}.site-footer{border-top:1px solid var(--line);padding:34px 0}.footer-top{display:flex;justify-content:space-between;align-items:center;gap:24px}.footer-top .brand img{width:34px;height:34px}.footer-top .brand-name{font-size:21px}.footer-links{display:flex;gap:25px;font-size:12px}.footer-bottom{display:flex;justify-content:space-between;margin-top:22px;font-size:10px;gap:24px;color:var(--muted)}
.document{max-width:780px;padding-block:60px 90px}.document h1{font-size:38px;margin-bottom:20px}.document .document-lead{font-size:18px;margin-bottom:15px}.document .updated{font-size:12px;margin-bottom:45px}.document h2{font-size:23px;margin-top:42px;margin-bottom:16px;scroll-margin-top:110px;letter-spacing:-.02em}.document p,.document li{font-size:15px;line-height:1.95}.document p+p{margin-top:16px}.document a{text-decoration:underline;text-underline-offset:4px;color:var(--blue)}.document ul,.document ol{padding-left:25px}.document code{background:var(--blue-soft);color:var(--ink);padding:3px 6px;border-radius:4px;font-size:13px;overflow-wrap:anywhere}.document .back-link{display:inline-flex;align-items:center;gap:8px;font-size:13px;margin-bottom:35px}.document .callout{padding:24px;background:var(--blue-soft);border-radius:16px;margin-top:24px}.document .callout p{font-size:13px}.not-found{padding-block:130px;text-align:center}.not-found p{margin:20px 0 32px}.noscript-tabs{padding:14px;font-size:13px;text-align:center;background:var(--yellow-soft)}
.download-grid.single-download{grid-template-columns:minmax(0,480px);justify-content:center}.site-header{height:76px}
@media(prefers-reduced-motion:no-preference){.hero-copy{animation:enter .65s both}.hero-visual{animation:enter .85s .1s both}.reveal-ready{opacity:0;transform:translateY(18px);transition:opacity .6s,transform .6s}.reveal-ready.revealed{opacity:1;transform:none}@keyframes enter{from{opacity:0;transform:translateY(15px)}to{opacity:1;transform:translateY(0)}}}
@media(min-width:1400px){.hero{min-height:690px}.hero-visual{height:585px}.phone-home{width:258px}.phone-card{width:236px}}
@media(max-width:1100px){.container{width:calc(100% - 64px)}.navigation{gap:22px}.hero{min-height:610px;gap:8px}.hero-visual{height:500px}.phone-home{width:215px;left:12px}.phone-card{width:197px;right:0}.hero h1{font-size:44px}.feature-panel{padding:45px 50px;gap:40px}.creation-layout,.local-layout{gap:45px}.math-resource img{width:220px;height:220px;right:-22px}.resource-example{padding:28px}.faq-layout{gap:45px}.download-surface{padding:42px 30px 30px}}
@media(max-width:900px){.navigation{gap:16px;font-size:12px}.nav-shell{gap:18px}.nav-tools{gap:8px}.hero h1{font-size:38px}.hero-description{font-size:16px}.hero-visual{height:455px}.phone-home{width:188px;left:5px;top:18px}.phone-card{width:174px;right:0;bottom:10px}.hero{min-height:540px}.hero-copy{padding-bottom:0}.hero .actions{gap:20px}.hero .button{padding-inline:20px}.hero .text-link{font-size:13px}.feature-panel{padding:40px;gap:28px}.tab-list button{padding:12px 17px}.feature-screen{width:220px}.resource-grid{grid-template-columns:1.2fr 1fr}.math-resource>div{max-width:64%}.math-resource img{width:175px;height:175px;right:-24px;bottom:0}.word-stack span{padding:8px 15px}.creation-layout{gap:35px}.editor-figure{padding-inline:22px;height:590px}.local-layout{gap:35px}.download-option{padding:24px}.download-option .button{padding-inline:12px}}
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158px)}.phone-card{width:166px;right:calc(50% - 153px);bottom:4px}.phone{border-width:4px;border-radius:24px}.phone img{border-radius:19px}.learning-path{padding:21px 0;gap:5px}.learning-path a{flex-direction:column;gap:8px;font-size:11px}.learning-path a>.icon{width:25px;height:25px}.path-arrow .icon{width:13px;height:13px}.section{padding-block:65px}.section-heading{margin-bottom:30px}.section-heading p{font-size:14px;margin-top:15px}.section-heading h2{line-height:1.45;font-size:30px}.section-heading h2 span{display:block}.tab-list{display:grid;grid-template-columns:1fr 1fr;width:100%;gap:5px;padding:6px;margin-bottom:22px}.tab-list button{justify-content:center;padding:11px 8px;font-size:12px;gap:7px}.tab-list button .icon{width:17px;height:17px}.experience-stage{border-radius:22px}.feature-panel{display:flex;flex-direction:column;padding:32px 25px;gap:32px;min-height:0;align-items:stretch}.feature-copy h3{font-size:28px;line-height:1.4}.feature-copy>p{font-size:14px;margin-top:17px;max-width:none}.feature-screen{width:226px;align-self:center}.feature-screen img{border-width:4px}.recall-demo{margin-top:22px;max-width:none;padding:20px}.demo-note{font-size:10px}.check-list{font-size:12px;gap:13px;margin-top:23px}.resource-section{padding-top:0;padding-bottom:40px}.resource-grid{grid-template-columns:1fr;gap:16px}.resource-example{padding:27px;min-height:250px;border-radius:22px}.resource-example h3{font-size:23px}.math-resource>div{max-width:64%}.math-resource img{width:200px;height:200px;right:-22px;bottom:3px}.resource-example p{font-size:13px}.resource-facts{font-size:10px;margin-top:20px}.methods-resource{min-height:250px}.methods-resource p{max-width:300px}.word-stack{margin-top:22px}.word-stack span{padding:8px 22px}.resource-footnote{align-items:flex-start;font-size:11px;line-height:1.8;margin-top:18px}.resource-footnote .icon{margin-top:2px}.creation-layout,.local-layout{display:flex;flex-direction:column;gap:32px;align-items:stretch}.creation-copy h2,.local-copy h2,.faq-layout h2{font-size:30px}.creation-copy>p:not(.eyebrow){font-size:14px}.creation-steps{gap:20px;margin-block:26px}.creation-steps strong{font-size:14px}.creation-steps span{font-size:12px}.editor-figure{height:540px;padding:28px 30px 18px;border-radius:22px}.editor-figure img{max-width:265px}.learning-illustration{border-radius:22px;order:1}.local-copy{order:0}.local-copy>p{font-size:14px}.local-points{gap:20px}.local-points h3{font-size:15px}.local-points p{font-size:13px}.faq-layout{display:flex;flex-direction:column;gap:30px}.faq-layout h2 br{display:none}.faq-layout h2{margin-bottom:16px}.faq-list summary{font-size:14px}.faq-list details p{font-size:13px}.faq-list details{padding-block:19px}#download{padding-top:25px}.download-surface{padding:32px 20px 24px;border-radius:24px}.download-mark{width:55px;height:55px;margin-bottom:18px}.download-surface .section-heading h2{font-size:28px}.download-grid{grid-template-columns:1fr;gap:17px}.download-option{padding:24px 20px;border-radius:17px}.download-option>p{font-size:12px}.download-platform h3{font-size:20px}.download-option .button{font-size:13px}.download-option .download-meta{font-size:10px}.release-note{font-size:10px;text-align:left;line-height:1.9}.footer-top{flex-direction:column;align-items:flex-start;gap:22px}.footer-links{gap:22px;font-size:12px;flex-wrap:wrap}.footer-bottom{flex-direction:column;gap:7px;font-size:10px;margin-top:22px}.site-footer{padding-block:28px}.document{padding-block:36px 60px}.document h1{font-size:32px}.document .document-lead{font-size:16px}.document h2{font-size:22px;margin-top:32px}.document p,.document li{font-size:14px}.document code{font-size:11px}.document .updated{margin-bottom:30px}}
@media(max-width:360px){.container{width:calc(100% - 32px)}.nav-tools{gap:6px}.nav-tools .small{padding:10px 11px}.brand-en{display:none}.hero h1{font-size:34px}.hero-visual{height:385px}.phone-home{width:165px;left:calc(50% - 133px)}.phone-card{width:149px;right:calc(50% - 133px)}.learning-path{gap:4px}.learning-path a{font-size:10px}.math-resource img{width:170px;height:170px;right:-32px}.math-resource>div{max-width:67%}.resource-example{padding:24px}.feature-panel{padding-inline:20px}.download-surface{padding-inline:16px}.download-option{padding-inline:16px}.download-option .button{font-size:12px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation:none!important;transition:none!important}.reveal-ready{opacity:1;transform:none}}
@media print{.site-header,.site-footer,.tab-list,.learning-path,.actions,.recall-demo,.download-grid{display:none}.section{padding-block:25px}.container{width:100%}.feature-panel[hidden]{display:grid!important}.reveal-ready{opacity:1;transform:none}}