/* A quiet glass surface, aligned to the header's typography and lilac starlight. */
.language-nav,.header .language-nav{display:flex;align-items:center;margin:0;gap:0;font-family:'Red Hat Display','OPPO Sans',sans-serif;line-height:1.5}
.language-control{position:relative}
.language-trigger{display:flex;align-items:center;justify-content:center;gap:10px;min-height:44px;padding:8px 0 8px 10px;border:0;background:none;color:#c8bfce;font:400 12px/20px 'Red Hat Display','OPPO Sans',sans-serif;cursor:pointer;transition:color .2s}
.language-trigger>span{display:block;line-height:20px;white-space:nowrap}
.language-trigger svg{display:block;flex:none;stroke:currentColor;stroke-width:1.25;stroke-linecap:round;stroke-linejoin:round}
.language-globe{width:16px;height:16px;opacity:.8}.language-chevron{width:12px;height:12px;margin-left:3px;transition:transform .22s}
.language-trigger:hover,.language-trigger[aria-expanded=true]{color:#eee5f7}
.language-trigger[aria-expanded=true] .language-chevron{transform:rotate(180deg)}
.language-menu{position:absolute;right:-12px;top:calc(100% + 10px);width:180px;padding:6px;border:1px solid #c4b1df2b;border-radius:12px;background:linear-gradient(145deg,#20152beb,#0c0913f5);backdrop-filter:blur(22px);-webkit-backdrop-filter:blur(22px);box-shadow:0 14px 40px #05020866,inset 0 1px 0 #f2dfff08;animation:language-arrive .2s ease-out;z-index:30}
.language-menu[hidden]{display:none}
.language-menu .language-option,.header .language-menu .language-option{display:flex;align-items:center;justify-content:space-between;gap:20px;min-height:44px;margin:0;padding:10px 12px;border-radius:7px;text-decoration:none;font:400 12px/20px 'Red Hat Display','OPPO Sans',sans-serif;letter-spacing:.015em;color:#b4a6c2;transition:background .18s,color .18s}
.language-option>span{display:block;line-height:20px}
.language-option .language-selected{display:block;flex:none;width:12px;height:12px;fill:#d2bfe7;opacity:0}
.language-menu .language-option[aria-current]{background:#c4b1df0b;color:#eee5f7}.language-option[aria-current] .language-selected{opacity:.9}
.language-menu .language-option:hover,.language-menu .language-option:focus-visible{background:#c4b1df16;color:#fff}
.language-trigger:focus-visible,.language-option:focus-visible{outline:1px solid #c4b1df80;outline-offset:3px}
@keyframes language-arrive{from{opacity:0;transform:translateY(-4px)}to{opacity:1;transform:translateY(0)}}
@media(max-width:700px){.language-trigger{font-size:11px;gap:8px}.language-globe{width:15px;height:15px}.language-menu{right:-5px;width:168px}}
@media(prefers-reduced-motion:reduce){.language-menu{animation:none}.language-trigger,.language-chevron,.language-option{transition:none!important}}
.contact-language{position:absolute;top:28px;right:7%}.contact-language nav{margin:0}
.contact-page .sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
:root:lang(zh-Hans){--serif:'Cosmos Serif','Songti SC','Noto Serif SC',serif;--sans:'OPPO Sans','PingFang SC','Microsoft YaHei','Noto Sans CJK SC',sans-serif}
:lang(zh-Hans) .wordmark,:lang(zh-Hans) .opening-brand{font-family:'Instrument Serif',Georgia,serif}
:lang(zh-Hans) h1,:lang(zh-Hans) h2,:lang(zh-Hans) h3,:lang(zh-Hans) blockquote{letter-spacing:.015em!important;font-weight:400; font-synthesis:none}
:lang(zh-Hans) em{font-style:normal}
:lang(zh-Hans) .hero h1{font-size:clamp(34px,3.7vw,66px);line-height:1.45}
:lang(zh-Hans) .hero .lead{line-height:1.9}
:lang(zh-Hans) .opening-caption>p{font-size:clamp(26px,3vw,44px);line-height:1.65;letter-spacing:.05em}
:lang(zh-Hans) .letter-paper h2{font-size:36px;line-height:1.4}
:lang(zh-Hans) .letter-paper p{font-size:15px;line-height:2;margin-bottom:19px}
:lang(zh-Hans) .letter-paper .letter-last-line{font-size:22px!important}
:lang(zh-Hans) .letter-signoff>span:last-child{font-family:'Instrument Serif',Georgia,serif}
:lang(zh-Hans) .reason .copy h2{font-size:clamp(40px,5.5vw,86px);line-height:1.5}
:lang(zh-Hans) .celestial-voice blockquote{font-size:clamp(26px,3.2vw,50px);line-height:1.6}
:lang(zh-Hans) .celestial-about h3{font-size:34px;line-height:1.5}
:lang(zh-Hans) .real-sky .copy h2,:lang(zh-Hans) .science .science-copy h2{font-size:clamp(34px,4.4vw,65px);line-height:1.55}
:lang(zh-Hans) .app-story h3{font-size:clamp(36px,4.4vw,66px);line-height:1.5}
:lang(zh-Hans) .app-copy .body-copy{line-height:2;max-width:355px}
:lang(zh-Hans) .research-list summary{font-size:23px;line-height:1.6}
:lang(zh-Hans) .closing .copy h2{font-size:clamp(38px,5.5vw,84px);line-height:1.5}
:lang(zh-Hans).contact-page{font-family:var(--sans)}
:lang(zh-Hans).contact-page h1{font-family:var(--serif);font-size:52px;line-height:1.5}
@media(max-width:700px){
 :lang(zh-Hans) .hero h1{font-size:clamp(30px,8.3vw,46px);line-height:1.45}
 :lang(zh-Hans) .hero-aside{font-size:10px;line-height:1.9}
 :lang(zh-Hans) .hero .lead{font-size:12px}
 :lang(zh-Hans) .opening-caption>p{font-size:24px;line-height:1.7}
 :lang(zh-Hans) .letter-paper h2{font-size:29px;margin-bottom:20px}
 :lang(zh-Hans) .letter-paper p{font-size:12px;line-height:2;margin-bottom:15px}
 :lang(zh-Hans) .letter-paper .letter-last-line{font-size:19px!important}
 :lang(zh-Hans) .reason .copy h2{font-size:clamp(29px,7.7vw,45px);line-height:1.65}
 :lang(zh-Hans) .celestial-voice blockquote{font-size:clamp(20px,5.7vw,29px);line-height:1.65}
 :lang(zh-Hans) .celestial-about h3{font-size:25px}
 :lang(zh-Hans) .real-sky .copy h2,:lang(zh-Hans) .science .science-copy h2{font-size:32px;line-height:1.6}
 :lang(zh-Hans) .app-story h3{font-size:34px;line-height:1.4;margin-bottom:18px}
 :lang(zh-Hans) .app-copy .body-copy{max-width:285px;font-size:12px;line-height:1.9}
 :lang(zh-Hans) .closing .copy h2{font-size:clamp(27px,7.5vw,43px)}
 :lang(zh-Hans) .research-list summary{font-size:20px}
 :lang(zh-Hans).contact-page h1{font-size:36px}
}

/* Song-style display type; OPPO Sans remains the reading face. */
:lang(zh-Hans) .hero h1{font-size:clamp(36px,4.1vw,72px);line-height:1.48;letter-spacing:.035em!important}
:lang(zh-Hans) .letter-paper h2{font-family:var(--serif);font-style:normal;font-weight:400;font-synthesis:none}
:lang(zh-Hans) .letter-paper p{font-size:17px;line-height:1.9}
:lang(zh-Hans) .opening-caption>p{font-weight:400}
:lang(zh-Hans) .letter-paper h2{font-size:37px}
:lang(zh-Hans) .celestial-voice blockquote{font-family:var(--serif);font-weight:400}
:lang(zh-Hans) .hero .lead,:lang(zh-Hans) .hero-aside{letter-spacing:.03em}
@media(max-width:700px){
 :lang(zh-Hans) .hero h1{font-size:clamp(30px,8.5vw,48px);letter-spacing:.02em!important}
 :lang(zh-Hans) .letter-paper h2{font-size:30px}
 :lang(zh-Hans) .letter-paper p{font-size:14px;line-height:1.9}
}
.header .language-option>span{margin:0;color:inherit}

:lang(zh-Hans) .letter-paper p,:lang(zh-Hans) .letter-signoff>span:first-child{font-family:var(--sans)}
:lang(zh-Hans) .principle h3{font-size:clamp(25px,2.7vw,38px);line-height:1.55}