:root{--paper:#f5f4ef;--ink:#17313e;--muted:#617075;--line:#d5dbd5;--accent:#c75630;--serif:Georgia,'Times New Roman','Noto Serif CJK SC','Songti SC',serif}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:110px}body{margin:0;background:var(--paper);color:var(--ink);font-family:Arial,'Noto Sans CJK SC','Microsoft Yahei',sans-serif}a{color:inherit;text-decoration:none}button{font:inherit}a,button{touch-action:manipulation}a:focus-visible,button:focus-visible{outline:2px solid var(--accent);outline-offset:5px}[hidden]{display:none!important}.skip{position:fixed;top:-100px;left:20px;background:white;padding:15px;z-index:30}.skip:focus{top:8px}header{height:98px;max-width:1440px;padding:0 64px;margin:auto;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:12px}.brand img{width:44px;height:44px;object-fit:contain}.brand strong{font-size:23px;letter-spacing:-1px}.brand strong span{display:block;font-size:9px;letter-spacing:3.4px;margin-top:4px}header nav{display:flex;gap:32px;align-items:center;font-size:12px}.language{display:flex;border:1px solid #ccd3cf;border-radius:3px;padding:3px;gap:2px}.language button{border:0;background:transparent;color:var(--muted);font-size:11px;min-height:30px;padding:6px 12px;cursor:pointer}.language button[aria-pressed=true]{background:var(--ink);color:white}.eyebrow{font-size:10px!important;font-family:Arial,sans-serif;letter-spacing:1.7px;font-weight:600;line-height:1.7!important;text-transform:uppercase}.home-hero{max-width:1440px;margin:auto;padding:76px 64px 70px;display:grid;grid-template-columns:1.1fr 1fr;align-items:center;gap:48px}.home-hero h1{font:normal clamp(64px,7.2vw,108px)/1.02 var(--serif);letter-spacing:-4px;margin:33px 0 26px}.hero-deck{font-size:17px;line-height:1.75;max-width:430px;color:var(--muted)}.issue{display:inline-block;margin-left:30px;color:var(--muted);font-size:9px;letter-spacing:1px}.text-link{display:flex;justify-content:space-between;max-width:215px;font-size:12px;border-bottom:1px solid var(--ink);padding:18px 0 12px;margin-top:28px}.orbital{background:#e5eae4;overflow:hidden;color:#294c57;position:relative}.orbital svg{display:block;width:100%;height:auto}.home-hero>.orbital{border-radius:50% 50% 3px 3px;padding-top:30px}.series-line{max-width:1312px;margin:auto;display:flex;justify-content:space-between;padding:20px 0;border-top:1px solid var(--ink);border-bottom:1px solid var(--line);font-size:10px;letter-spacing:1.3px}.stories{max-width:1312px;margin:auto}.story-row{display:grid;grid-template-columns:70px 1fr 280px;gap:30px;padding:40px 0;border-bottom:1px solid var(--line);align-items:center}.story-num{font-family:var(--serif);align-self:stretch;display:flex;flex-direction:column;justify-content:space-between;font-size:23px;color:var(--accent);padding:4px 0}.story-num span{font-size:23px}.story-copy .eyebrow{color:var(--accent);margin:0 0 14px}.story-copy h2{font:normal 36px/1.2 var(--serif);letter-spacing:-.8px;margin:0 0 14px}.deck{color:var(--muted);max-width:600px;font-size:14px;line-height:1.8;margin:0}.read{display:inline-block;font-size:11px;margin-top:24px}.mini-art .orbital{height:190px}.mini-art svg{height:100%;width:100%;object-fit:cover}.art-02{background:#e4e8ed;color:#566679}.art-02 svg{transform:rotate(9deg) scale(1.08)}.art-03{background:#eee4d7;color:#8c7662}.art-03 svg{transform:rotate(-12deg) scale(1.08)}.story-row:hover h2,.text-link:hover,.article-breadcrumb a:hover{color:var(--accent)}.story-row:hover .orbital{filter:brightness(.97)}.editor-note{max-width:1312px;margin:90px auto;display:grid;grid-template-columns:1fr 2fr;gap:50px}.editor-note h2{font:normal 39px/1.2 var(--serif);margin:0 0 25px}.editor-note p:not(.eyebrow){font-size:15px;line-height:1.9;max-width:650px;color:var(--muted)}.source-note{font-size:12px!important;color:var(--muted);line-height:1.8!important}footer{background:#19333f;color:#e9eee9;padding:48px max(40px,calc((100vw - 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.home-hero>.orbital text:first-of-type{display:none}

.hero-source{display:flex;justify-content:center;margin:26px 0 30px}.researchgate-button{display:inline-flex;align-items:center;justify-content:center;gap:18px;min-height:48px;padding:13px 22px;border:1px solid #ad4524;border-radius:4px;background:#b94d29;color:#fff;font-size:14px;font-weight:600;line-height:1.5;box-shadow:0 3px 0 #17313e12}.researchgate-button:hover{background:#973d20;border-color:#973d20}.researchgate-button>span:last-child{font-size:19px;line-height:1}.researchgate-button:focus-visible{outline:3px solid var(--ink);outline-offset:4px}@media(max-width:700px){.hero-source{margin:22px 0 26px}.researchgate-button{padding:12px 16px;font-size:13px;gap:12px;max-width:100%}}

/* AstroUp shared visual identity */
:root{--paper:#f7f5f0;--ink:#12345f;--muted:#46607e;--accent:#f5641e;--line:#d9dfe3;--serif:'Nunito',-apple-system,BlinkMacSystemFont,'PingFang SC','Microsoft YaHei',sans-serif}
body{font-family:'Nunito',-apple-system,BlinkMacSystemFont,'PingFang SC','Microsoft YaHei',sans-serif;padding-top:80px}.research-toolbar{height:58px;max-width:1440px;margin:auto;padding:0 5vw;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line)}.research-toolbar>a{font-size:10px;font-weight:750;letter-spacing:1.6px;color:var(--muted)}
.home-hero{padding-top:60px;padding-bottom:58px}.home-hero h1{font-weight:850;font-size:clamp(62px,6.6vw,96px);letter-spacing:-3px;line-height:1.08}.story-copy h2,.editor-note h2,.article-hero h1,.article-section h2,.source-card h2,.next-story h2{font-weight:800}.article-hero h1{font-size:clamp(42px,5vw,66px);line-height:1.16}.article-section p{font-family:Georgia,'Times New Roman',serif;color:#334b64}.key-idea p:last-child{font-weight:600;font-size:23px}.home-hero>.orbital{background:#e6edf0}.text-link,.read{font-weight:700}.researchgate-button{background:#f5641e;border-color:#f5641e;border-radius:999px;box-shadow:0 6px 16px #f5641e30}.researchgate-button:hover{background:#da4e0a;border-color:#da4e0a}.source-card{background:#edf0f2;border-radius:14px}footer{background:#12345f}.progress{top:80px}.skip{z-index:1100}
@media(max-width:850px){body{padding-top:72px}.progress{top:72px}.research-toolbar{padding:0 22px;height:54px}}
@media(max-width:700px){.home-hero{padding-top:36px}.home-hero h1{font-size:58px;letter-spacing:-2px}.article-hero h1{font-size:39px}.story-copy h2{font-size:27px}.key-idea p:last-child{font-size:21px}}
@media print{astroup-navigation,.research-toolbar{display:none}body{padding-top:0}}

/* Individually illustrated technical-column covers. */
.mini-art{overflow:hidden;border-radius:12px;border:1px solid #12345f0d;background:#e6edf0}.story-cover{display:block;width:100%;height:auto;aspect-ratio:28/19;object-fit:cover;transition:transform .35s ease}.story-row:hover .story-cover{transform:scale(1.025)}
@media(max-width:700px){.mini-art{display:block;grid-column:2;margin-top:4px;max-width:440px;width:100%}.story-num{grid-row:1/3}.story-cover{aspect-ratio:28/19}.story-row{row-gap:20px}}
@media(prefers-reduced-motion:reduce){.story-cover{transition:none}.story-row:hover .story-cover{transform:none}}