body{font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;max-width:920px;margin:0 auto;padding:30px 40px 80px;line-height:1.75;color:#0b0f1a;background:#fafbfc}
h1{font-size:30px;border-bottom:3px solid #38bdf8;padding-bottom:12px;margin-top:0}
h2{font-size:22px;color:#1f2937;border-left:5px solid #fbbf24;padding-left:12px;margin-top:36px;background:#fefefe}
h3{font-size:18px;color:#374151;margin-top:24px}
h4{font-size:15px;color:#4b5563}
a{color:#0ea5e9;text-decoration:none}
a:hover{text-decoration:underline}
code{background:#f3f4f6;padding:2px 6px;border-radius:4px;font-size:13.5px;font-family:'SF Mono',Menlo,monospace;color:#dc2626}
pre{background:#1f2937;color:#f9fafb;padding:14px;border-radius:8px;overflow-x:auto;font-size:13px;line-height:1.55}
pre code{background:transparent;color:inherit;padding:0}
table{border-collapse:collapse;width:100%;margin:14px 0;font-size:13.5px}
th,td{border:1px solid #e5e7eb;padding:8px 12px;text-align:left}
th{background:#eff6ff;color:#1e40af;font-weight:600}
tr:nth-child(even){background:#f9fafb}
blockquote{border-left:4px solid #a78bfa;padding:8px 14px;background:rgba(167,139,250,.06);margin:12px 0;border-radius:0 6px 6px 0;color:#374151;font-style:italic}
ul,ol{padding-left:24px}
li{margin:4px 0}
hr{border:none;border-top:1px solid #e5e7eb;margin:32px 0}
#TOC{background:#fff;border:1px solid #e5e7eb;border-radius:8px;padding:16px 20px;margin-bottom:32px;box-shadow:0 1px 3px rgba(0,0,0,.04)}
#TOC ul{padding-left:18px;list-style-type:none}
#TOC > ul{padding-left:0}
#TOC ul ul{padding-left:18px;font-size:13px;color:#6b7280}
#TOC a{color:#0b0f1a}
.back-link{position:fixed;top:14px;left:14px;background:#38bdf8;color:#fff;padding:8px 14px;border-radius:6px;font-size:13px;font-weight:600;box-shadow:0 4px 12px rgba(56,189,248,.3);z-index:100}
.back-link:hover{background:#0ea5e9;text-decoration:none;color:#fff}
@media (max-width:768px){body{padding:18px 16px 60px}.back-link{position:static;display:inline-block;margin-bottom:14px}}