/* PG电子 · responsive reading system */
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*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:90px}body{margin:0;background:var(--bg);color:var(--body);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif;font-size:16px;line-height:1.8}a{color:var(--lightblue);text-decoration:none}a:hover{text-decoration:underline}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--ice);outline-offset:3px}button{font:inherit;cursor:pointer}h1,h2,h3{color:var(--title);line-height:1.36;margin:0 0 17px}h1{font-size:32px}h2{font-size:24px}h3{font-size:19px}p{margin:0 0 17px}figure{margin:0}figcaption{font-size:13px;color:var(--muted);margin:10px 0 0}ul,ol{padding-left:23px}li{margin:5px 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