:root{--bg:#F4F7FA;--white:#fff;--soft:#EAF1F6;--aqua:#E9F8F8;--navy:#102E46;--deep:#163C57;--teal:#13B8C5;--blue:#237BD3;--title:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:20px}body{margin:0;background:var(--bg);color:var(--text);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;font-size:16px;line-height:1.8}body.drawer-open{overflow:hidden}a{color:#1267aa;text-underline-offset:3px}a:hover{color:#0b516f}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--teal);outline-offset:3px}h1,h2,h3,h4{line-height:1.36;color:var(--title);margin:0 0 .65em}h1{font-size:clamp(2rem,3vw,2.7rem)}h2{font-size:clamp(1.45rem,2.1vw,1.75rem)}h3{font-size:1.22rem}p{margin:0 0 1.05em}ul,ol{padding-left:1.5em}li{margin:.3em 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/* Progressive enhancement: retain a visible channel index when scripts are disabled. */
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