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@media(min-width:1500px){.hero{min-height:790px}}@media(max-width:1000px){.hero{gap:25px}.orbit{width:330px;height:330px}.phone{width:235px}.hero-art{min-height:580px}.math-plus{left:0}.math-times{right:-5px}h1{letter-spacing:-2px}.caption{left:0}.mode-copy{min-height:285px;padding:26px}.wrap{width:calc(100% - 48px)}}@media(max-width:700px){.wrap{width:calc(100% - 40px)}.nav{min-height:85px;gap:10px}.brand{font-size:20px}.brand-icon{width:32px;height:32px;font-size:25px}nav{gap:12px;font-size:12px}.nav nav>a{display:none}.hero{grid-template-columns:1fr;gap:10px;padding-top:36px;padding-bottom:35px}.hero-copy{max-width:520px}.hero h1{font-size:57px;letter-spacing:-3px}.lead{font-size:16px}.hero-note{margin-top:24px}.hero-art{min-height:610px;margin-top:18px}.phone{width:252px}.orbit{width:310px;height:310px}.math-plus{left:5%;top:60px}.math-times{right:4%;bottom:130px}.caption{left:1%;bottom:0}.ribbon{padding:17px 0}.ribbon>div{font-size:11px;letter-spacing:2px}.ribbon span{margin:0 16px}.how{padding-top:65px;padding-bottom:65px}.section-head h2,h2{font-size:33px;letter-spacing:-1px}.steps{grid-template-columns:1fr;gap:20px;margin:32px 0}.steps article{padding-top:18px}.steps h3{margin-top:13px}.modes{padding:60px 0}.mode-grid{grid-template-columns:1fr}.mode-copy{min-height:0;padding:28px}.screenshot-window{height:360px}.closing{padding-top:60px;padding-bottom:55px}.closing h2{font-size:32px}.footer{flex-wrap:wrap;padding:26px 0}.footer nav{width:100%;padding-top:8px}html[lang="zh-CN"] .hero h1{font-size:48px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}