@font-face{font-family:Inter;src:url('assets/Inter.woff2') format('woff2');font-style:normal;font-weight:100 900;font-display:swap}
:root{--bg:#111214;--panel:#191a1e;--ink:#f0eff3;--muted:#a6a5ad;--line:rgba(233,229,247,.14);--accent:#c6b5ef;--font:Inter,'PingFang SC','Microsoft YaHei',sans-serif;color-scheme:dark;font-family:var(--font);background:var(--bg);color:var(--ink);font-synthesis:none}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:30px}body{margin:0;overflow-x:hidden}button,a,input{-webkit-tap-highlight-color:transparent}button,input{font:inherit}button,a{touch-action:manipulation}a{color:inherit;text-decoration:none}button{color:inherit}button:not(:disabled),a{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible,[tabindex]:focus-visible{outline:2px solid var(--accent);outline-offset:6px}button{border:0}h1,h2,h3,p{margin:0}button:disabled{opacity:.3;cursor:default}::selection{background:var(--accent);color:#17141c}.skip-link{position:absolute;top:-100px;z-index:200;padding:14px;background:var(--accent);color:#111}.skip-link:focus{top:12px}
.header{height:96px;padding:0 4.2%;display:flex;align-items:center;gap:72px;position:relative;z-index:3;border-bottom:1px solid var(--line);background:rgba(17,18,20,.2)}.brand{display:flex;align-items:center;gap:12px;flex-shrink:0}.brand svg{width:38px;height:38px;fill:none;stroke:var(--ink);stroke-width:1.4;stroke-linejoin:round}.brand>span{font-size:23px;font-weight:500;letter-spacing:.12em}.brand small{font-size:8px;display:block;letter-spacing:.22em;margin-top:6px;font-weight:400}.desktop-nav{display:flex;align-items:center;gap:26px;color:#b6b5bd;font-size:14px}.desktop-nav a:hover{color:#fff}.desktop-nav span{color:#66646e;font-size:12px}.header-action{margin-left:auto;display:flex;gap:22px;align-items:center;font-size:13px;letter-spacing:.1em}.small-square{width:6px;height:6px;background:var(--accent);display:inline-block}.menu-button{background:none;display:none;width:40px;padding:8px}.menu-button span{display:block;width:24px;height:1px;background:#eee;margin:7px 0}.mobile-nav{position:absolute;top:80px;left:0;right:0;background:#19191e;z-index:8;padding:24px}.mobile-nav:not([hidden]){display:flex;gap:28px}
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.section{padding:75px 4.2%}.section-heading{display:flex;justify-content:space-between;gap:40px;align-items:flex-end}.section-heading h2{font-size:clamp(26px,2.6vw,40px);line-height:1.4;font-weight:400;letter-spacing:-.03em;margin-top:17px}.lavender{color:var(--accent)}.section-intro{font-size:14px;line-height:1.95;color:var(--muted)}.subjects{padding-bottom:58px;overflow:hidden;background:radial-gradient(ellipse at 50% 48%,#232129 0,transparent 54%)}.subject-explorer{position:relative;margin-top:26px}.orbit-stage{position:relative;height:387px;width:100%;touch-action:pan-y;cursor:grab;user-select:none;outline-offset:-2px!important}.orbit-stage.dragging{cursor:grabbing}.orbit-guide{width:85%;max-width:1170px;position:absolute;height:176px;border:1px solid rgba(198,181,239,.12);border-radius:50%;left:50%;top:176px;transform:translateX(-50%)}.subject-cards{position:absolute;inset:0;perspective:1300px}.subject-card{position:absolute;left:50%;top:22px;width:236px;height:307px;padding:18px 21px 19px;text-align:left;background:linear-gradient(155deg,#26242d,#18191d 70%);border:1px solid rgba(225,211,255,.2);transform-origin:center;will-change:transform;overflow:hidden;transition:border-color .2s,box-shadow .2s;user-select:none;-webkit-user-drag:none}.subject-card.is-active{border-color:rgba(207,185,255,.58);box-shadow:0 18px 80px -32px #77638b6b;background:linear-gradient(155deg,#302b3b,#1a1a20 73%)}.subject-card:hover{border-color:rgba(223,208,251,.7)}.subject-card>header{display:flex;justify-content:space-between;font-size:10px;letter-spacing:.16em;color:#b8b0c8}.subject-diagram{height:173px;display:flex;align-items:center;justify-content:center;padding:8px 0 0;pointer-events:none}.subject-diagram svg{width:100%;height:100%;overflow:visible}.subject-card h3{font-size:27px;letter-spacing:.05em;font-weight:400}.subject-card .card-subtitle{font-size:12px;color:#aaa2b8;margin-top:6px}.subject-card .card-open{position:absolute;right:21px;bottom:25px;font-size:22px;color:#b7a4d5;font-weight:200}.orbit-navigation{display:flex;justify-content:center;align-items:center;gap:40px;margin-top:7px}.round-button{width:38px;height:38px;border:1px solid #4a4551;border-radius:50%;background:transparent;font-size:25px;line-height:1;font-family:Arial;transition:background .2s}.round-button:hover{background:#2c2537}.orbit-caption{text-align:center;min-width:268px}.orbit-caption>span{font-size:11px;letter-spacing:.16em;color:#a793c1}.orbit-caption>p{font-size:15px;margin-top:10px}.subject-tabs{display:flex;align-items:center;justify-content:center;gap:9px;flex-wrap:wrap;margin-top:28px}.subject-tabs button{padding:8px 15px;border-radius:30px;background:transparent;color:#a9a5b0;font-size:13px;border:1px solid transparent;transition:.2s}.subject-tabs button[aria-pressed=true]{border-color:#6a5b82;color:#e0cffb;background:#c6b5ef12}.subject-tabs button:hover{color:#eee}.drag-hint{font-size:11px;color:#88818f;display:flex;gap:8px;align-items:center;justify-content:center;margin-top:22px;letter-spacing:.09em}.drag-hint svg{fill:none;stroke:currentColor;stroke-width:1.2}
.selected{border-top:1px solid var(--line);padding-top:73px;padding-bottom:86px}.lesson-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:25px;margin-top:39px}.lesson-card{display:block;text-align:left;padding:0;background:transparent;border:1px solid var(--line);overflow:hidden;transition:transform .3s,border-color .3s}.lesson-card:hover{transform:translateY(-6px);border-color:#8e7ba8}.lesson-art{height:235px;position:relative;overflow:hidden;background:radial-gradient(ellipse at 62% 50%,#34303e,#191a1f 72%);padding:25px}.lesson-art>span{position:absolute;top:20px;left:22px;font-size:11px;letter-spacing:.1em;color:#c7c0d1}.lesson-art svg{width:100%;height:100%;filter:drop-shadow(0 5px 12px #c6b5ef22)}.lesson-art .math-caption{font-size:20px;letter-spacing:.05em;position:absolute;bottom:20px;right:25px}.lesson-info{border-top:1px solid var(--line);padding:22px 23px 24px}.lesson-meta{display:flex;justify-content:space-between;font-size:11px;letter-spacing:.06em;color:#a79caf}.lesson-info h3{font-size:23px;font-weight:400;line-height:1.5;margin-top:13px}.lesson-info>p{font-size:13px;line-height:1.7;color:#99939f;margin-top:6px}.lesson-info .lesson-cta{display:block;margin-top:21px;font-size:12px;color:#d5c3ef}.lesson-art.chinese-art{background:radial-gradient(ellipse at 50% 90%,#41424c,#1c1c22 76%)}
.about{border-top:1px solid var(--line);position:relative;overflow:hidden;padding-bottom:77px;background:linear-gradient(110deg,#17161b,#111214 80%)}.about-top{display:flex;align-items:flex-start;justify-content:space-between}footer{padding:31px 4.2%;border-top:1px solid var(--line);display:flex;align-items:center;gap:38px;color:#8f8a98;font-size:11px}.footer-brand{font-size:18px;letter-spacing:.13em;color:#d1cbd8}.footer-brand small{display:block;font-size:7px;letter-spacing:.19em;margin-top:7px}footer>p{color:#9d97a7}footer>span{margin-left:auto}footer>a:last-child{color:#c9c2d4}
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@media(min-width:1700px){.hero{min-height:760px}.hero-content{padding-top:115px}.section{padding-left:max(4.2%,calc((100vw - 1620px)/2));padding-right:max(4.2%,calc((100vw - 1620px)/2))}.orbit-stage{height:405px}}
@media(max-width:1100px){.header{gap:40px}.header-action{font-size:12px;gap:13px}.desktop-nav{gap:16px}.hero{min-height:610px}.hero-content{padding-top:73px}.hero h1{font-size:58px}.vertical-note{display:none}.section{padding-top:58px}.section-intro{font-size:13px}.lesson-grid{gap:17px}.lesson-info{padding:19px}.lesson-info h3{font-size:20px}.lesson-art{height:205px}}
@media(max-width:760px){.header{height:80px;padding:0 6%;gap:16px}.brand>span{font-size:20px}.brand small{font-size:7px}.brand svg{width:31px;height:31px}.desktop-nav,.header-action{display:none}.menu-button{display:block;margin-left:auto}.hero{min-height:764px}.hero-content{padding:41px 6% 0;max-width:none}.hero .eyebrow{font-size:10px}.hero h1{font-size:clamp(40px,8.9vw,65px);line-height:1.24;margin:21px 0 18px;position:relative;z-index:1}.hero-description{font-size:13px;line-height:1.8}.hero .button{margin-top:21px;min-height:46px;font-size:13px;padding:0 22px;gap:25px}.hero-footer{left:6%;right:6%;bottom:24px}.hero-footer>p{font-size:10px}.hero-footer small{font-size:8px;margin-top:9px}.scroll-note{font-size:10px;gap:10px}.section{padding:48px 6%}.section-heading{display:block}.section-heading h2{font-size:27px;margin-top:13px}.section-intro{margin-top:15px;line-height:1.8;font-size:13px}.section-intro br{display:none}.eyebrow{font-size:9px;letter-spacing:.16em}.subjects{padding-left:0;padding-right:0}.subjects .section-heading{padding:0 6%}.subject-explorer{margin-top:18px}.orbit-stage{height:335px}.subject-card{top:23px;width:209px;height:276px;padding:16px 18px}.subject-diagram{height:150px}.subject-card h3{font-size:25px}.subject-card .card-subtitle{font-size:11px}.subject-card>header{font-size:9px}.orbit-guide{height:130px;width:125%;top:181px}.orbit-caption{min-width:215px}.orbit-caption>p{font-size:13px}.orbit-navigation{gap:17px}.round-button{width:34px;height:34px}.subject-tabs{padding:0 6%;gap:4px;margin-top:24px}.subject-tabs button{font-size:12px;padding:7px 11px}.drag-hint{font-size:10px}.lesson-grid{grid-template-columns:1fr;gap:22px;margin-top:28px}.lesson-art{height:244px}.lesson-info{padding:21px}.lesson-info h3{font-size:23px}.lesson-info>p{font-size:14px}.lesson-meta{font-size:12px}.lesson-info .lesson-cta{font-size:13px;margin-top:15px}footer{padding:29px 6%;display:grid;grid-template-columns:1fr auto;gap:23px;font-size:10px}footer>p{display:none}footer>span{margin:0;grid-column:1;grid-row:2}.footer-brand{font-size:19px}footer>a:last-child{grid-column:2;grid-row:2}.lesson-preview{padding:22px}.lesson-slide{grid-template-columns:1fr;gap:15px;margin-top:20px}.slide-visual{min-height:205px}.slide-visual svg{height:205px}.preview-title{font-size:25px}.slide-copy h3{font-size:21px}.slide-copy p{font-size:14px}.dialog-header{padding:12px 20px}.preview-controls{flex-wrap:wrap;gap:12px}.slide-control{padding:10px 15px}.slide-dots{gap:5px}.slide-dots button{width:18px}.slide-count{display:none}}
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