:root{--green:#55d6a1;--cyan:#72cfe2;--ink:#e8f4ef;--muted:#91a3aa;--bg:#091116;--ease:cubic-bezier(.22,1,.36,1)}
*{box-sizing:border-box}html{scroll-behavior:smooth;background:var(--bg)}body{margin:0;color:var(--ink);background:var(--bg);font-family:"PingFang SC","Microsoft YaHei",system-ui,sans-serif}a{color:inherit;text-decoration:none}.classroom-motion-pending>header,.classroom-motion-pending>main,.classroom-motion-pending>footer{opacity:0}.is-page-ready>header,.is-page-ready>main,.is-page-ready>footer{opacity:1;transition:opacity .6s ease}
.aurora-boot{position:fixed;inset:0;z-index:1000;display:grid;color:#e8f4ef;background:#0a1115;place-items:center;overflow:hidden;transition:opacity 520ms var(--ease),visibility 0s linear 520ms}.aurora-boot::before{position:absolute;inset:0;content:"";opacity:.2;background-image:linear-gradient(rgba(114,207,226,.08) 1px,transparent 1px),linear-gradient(90deg,rgba(114,207,226,.08) 1px,transparent 1px);background-size:56px 56px;mask-image:radial-gradient(circle at center,#000,transparent 72%)}.aurora-boot__field{position:absolute;inset:0;display:grid;place-items:center}.aurora-boot__field i{position:absolute;width:min(72vw,820px);aspect-ratio:1.9;border:1px solid rgba(93,210,170,.13);border-radius:50%;transform:rotate(-12deg);animation:orbit 1.25s var(--ease) both}.aurora-boot__field i:nth-child(2){width:min(60vw,680px);animation-delay:80ms}.aurora-boot__field i:nth-child(3){width:min(48vw,540px);animation-delay:150ms}.aurora-boot__content{position:relative;display:grid;width:min(340px,calc(100vw - 70px));justify-items:center;text-align:center}.aurora-boot__mark{position:relative;display:block;width:54px;height:54px;margin-bottom:25px;border:1px solid rgba(114,207,226,.65);border-radius:50%;animation:mark .7s var(--ease) both}.aurora-boot__mark::before{position:absolute;inset:8px;content:"";border:1px solid rgba(85,214,161,.25);border-radius:50%}.aurora-boot__mark i{position:absolute;left:13px;width:29px;height:1px;background:linear-gradient(90deg,var(--green),var(--cyan));transform:rotate(-18deg) scaleX(0);transform-origin:left;animation:draw .52s var(--ease) .26s forwards}.aurora-boot__mark i:nth-child(1){top:16px}.aurora-boot__mark i:nth-child(2){top:26px;left:10px;width:34px;animation-delay:.34s}.aurora-boot__mark i:nth-child(3){top:36px;left:16px;width:23px;animation-delay:.42s}.aurora-boot__content p{margin:0 0 9px;color:var(--green);font:8px/1 ui-monospace,monospace;letter-spacing:.3em}.aurora-boot__content strong{font-size:19px;font-weight:520;letter-spacing:.08em}.aurora-boot__content small{color:#718087;font:7px/1 ui-monospace,monospace;letter-spacing:.18em}.aurora-boot__progress{width:100%;height:1px;margin:27px 0 13px;background:rgba(255,255,255,.09);overflow:hidden}.aurora-boot__progress i{display:block;width:100%;height:100%;background:linear-gradient(90deg,var(--green),var(--cyan));transform:scaleX(0);transform-origin:left;animation:progress .82s cubic-bezier(.65,0,.35,1) .18s forwards}.aurora-boot.is-complete{visibility:hidden;opacity:0}
.classroom-header{position:fixed;top:0;left:0;right:0;z-index:20;display:flex;justify-content:space-between;align-items:center;padding:24px clamp(24px,5vw,76px);background:linear-gradient(180deg,rgba(9,17,22,.92),transparent)}.classroom-brand{display:flex;gap:13px;align-items:center}.classroom-mark{position:relative;width:34px;height:34px;border:1px solid rgba(114,207,226,.5);border-radius:50%}.classroom-mark i{position:absolute;left:8px;width:18px;height:1px;background:linear-gradient(90deg,var(--green),var(--cyan));transform:rotate(-18deg)}.classroom-mark i:nth-child(1){top:10px}.classroom-mark i:nth-child(2){top:16px}.classroom-mark i:nth-child(3){top:22px}.classroom-header nav{display:flex;gap:30px;font-size:13px;color:#adbac0}.classroom-hero{position:relative;display:grid;min-height:100vh;align-items:center;padding:140px clamp(24px,8vw,140px) 90px;overflow:hidden}.classroom-grid{position:absolute;inset:0;opacity:.18;background-image:linear-gradient(rgba(114,207,226,.1) 1px,transparent 1px),linear-gradient(90deg,rgba(114,207,226,.1) 1px,transparent 1px);background-size:64px 64px;mask-image:linear-gradient(90deg,#000,transparent 82%)}.classroom-orbits{position:absolute;right:-8vw;top:15%;width:min(55vw,760px);aspect-ratio:1}.classroom-orbits i{position:absolute;inset:12%;border:1px solid rgba(85,214,161,.16);border-radius:50%;transform:rotate(-16deg)}.classroom-orbits i:nth-child(2){inset:25%;border-color:rgba(114,207,226,.2)}.classroom-orbits i:nth-child(3){inset:38%}.classroom-hero__copy{position:relative;z-index:2;max-width:900px}.classroom-hero__copy>span,.classroom-section>span{color:var(--green);font:10px/1 ui-monospace,monospace;letter-spacing:.25em}.classroom-hero h1{margin:30px 0;font-size:clamp(48px,6.6vw,108px);font-weight:460;line-height:1.03;letter-spacing:-.06em}.classroom-hero p{max-width:690px;color:var(--muted);font-size:17px;line-height:1.9}.classroom-actions{display:flex;gap:14px;margin-top:42px}.classroom-actions a{padding:14px 22px;border:1px solid rgba(255,255,255,.18);border-radius:999px}.classroom-actions .primary{color:#07110d;background:var(--green);border-color:var(--green)}.classroom-status{position:absolute;right:5vw;bottom:45px;display:grid;gap:5px;text-align:right;font:9px/1.5 ui-monospace,monospace;color:#778890}.classroom-status span{color:var(--green)}.classroom-section{padding:150px clamp(24px,10vw,170px);background:#eef2ef;color:#15201c}.classroom-section h2{max-width:1100px;margin:28px 0;font-size:clamp(38px,5vw,76px);font-weight:480;line-height:1.15;letter-spacing:-.05em}.classroom-section p{max-width:720px;color:#64716c;font-size:17px;line-height:1.9}.classroom-features{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:#27322e;border-top:1px solid #27322e}.classroom-features article{min-height:330px;padding:55px;background:#101a17}.classroom-features span{color:var(--green);font:10px ui-monospace,monospace}.classroom-features h3{margin:70px 0 18px;font-size:30px;font-weight:500}.classroom-features p{color:var(--muted);line-height:1.8}footer{display:flex;justify-content:space-between;padding:30px clamp(24px,5vw,76px);color:#72817c;font-size:12px}
@keyframes orbit{from{opacity:0;transform:rotate(-12deg) scale(.72)}to{opacity:1;transform:rotate(-12deg) scale(1)}}@keyframes mark{from{opacity:0;transform:scale(.72) rotate(-12deg)}to{opacity:1;transform:scale(1)}}@keyframes draw{to{transform:rotate(-18deg) scaleX(1)}}@keyframes progress{0%{transform:scaleX(0)}72%{transform:scaleX(.82)}100%{transform:scaleX(1)}}
@media(max-width:760px){.classroom-header nav a:not(:last-child){display:none}.classroom-hero{padding-inline:24px}.classroom-status{display:none}.classroom-actions{align-items:flex-start;flex-direction:column}.classroom-features{grid-template-columns:1fr}.classroom-features article{min-height:250px}.classroom-features h3{margin-top:45px}}@media(prefers-reduced-motion:reduce){.aurora-boot{display:none!important}*{scroll-behavior:auto!important;animation-duration:.01ms!important;transition-duration:.01ms!important}}