:root{--sidebar-w: 268px;--toc-w: 220px;--content-max: 720px;--ink: #16181d;--ink-soft: #3a3f4a;--ink-mute: #6b7280;--ink-faint: #9aa1ad;--line: #e6e3dc;--line-soft: #efece5;--paper: #fbfaf7;--paper-2: #f4f2ec;--surface: #ffffff;--accent: #c2410c;--accent-ink: #9a3412;--accent-wash:#fdf1e9;--code-bg: #1b1d23;--code-fg: #e7e4dd;--code-line: #2c2f38;--green: #15803d;--cat-systems: #0ea5e9;--cat-ai: #8b5cf6;--cat-eng: #10b981;--r-sm: 6px;--r-md: 10px;--r-lg: 14px;--t-fast: .13s cubic-bezier(.16, 1, .3, 1);--t-mid: .22s cubic-bezier(.16, 1, .3, 1);--font-serif: "Newsreader", Georgia, "Times New Roman", serif;--font-sans: "Inter", system-ui, -apple-system, sans-serif;--font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth}body{font-family:var(--font-sans);background:var(--paper);color:var(--ink);line-height:1.6;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}a{color:inherit;text-decoration:none}img{max-width:100%;height:auto}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important;scroll-behavior:auto!important}}.skip-link{position:absolute;left:-9999px;top:0;z-index:200;background:var(--accent);color:#fff;padding:10px 16px;border-radius:0 0 var(--r-sm) 0;font-size:.85rem;font-weight:600}.skip-link:focus{left:0}.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{--header-h: 57px}#progress{position:fixed;top:0;left:0;height:3px;width:0%;background:var(--accent);z-index:70;transform-origin:left center;transition:width 80ms linear;will-change:width}.site-header{position:sticky;top:0;z-index:65;background:color-mix(in srgb,var(--paper) 88%,transparent);backdrop-filter:saturate(1.1) blur(8px);border-bottom:1px solid var(--line)}.site-header-inner{display:flex;align-items:center;gap:1rem;height:var(--header-h);padding:0 clamp(1rem,3vw,2rem)}.site-header .menu-btn{display:none}.site-header .brand{font-family:var(--font-sans);font-weight:700;letter-spacing:-.01em;font-size:.98rem;line-height:1.15;color:var(--ink)}.site-header .brand span{color:var(--accent)}.site-header .brand small{display:block;font-weight:500;font-size:.72rem;color:var(--ink-mute);letter-spacing:.02em}.site-header .brand:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:var(--r-sm)}.site-header .topnav{margin-left:auto;display:flex;gap:1.4rem;font-family:var(--font-sans);font-size:.86rem}.site-header .topnav a{color:var(--ink-soft);font-weight:500;padding:4px 2px;transition:color var(--t-fast)}.site-header .topnav a:hover{color:var(--accent)}.site-header .topnav a[aria-current=page]{color:var(--accent-ink);font-weight:600}.site-header .topnav a:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:var(--r-sm)}@media(max-width:780px){.site-header .menu-btn{display:inline-flex;align-items:center;justify-content:center;width:38px;height:38px;border:1px solid var(--line);border-radius:var(--r-sm);background:var(--surface);cursor:pointer;color:var(--ink-soft);transition:border-color var(--t-fast),color var(--t-fast)}.site-header .menu-btn:hover{border-color:var(--accent);color:var(--accent)}.site-header .menu-btn:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.site-header .topnav{display:none}}@media(prefers-reduced-motion:reduce){#progress{transition:none}}.shell{display:grid;grid-template-columns:var(--sidebar-w) minmax(0,1fr) var(--toc-w);min-height:100vh}.shell.no-toc{grid-template-columns:var(--sidebar-w) minmax(0,1fr)}.sidebar{position:sticky;top:var(--header-h);align-self:start;height:calc(100vh - var(--header-h));overflow-y:auto;background:var(--paper-2);border-right:1px solid var(--line);padding:26px 18px 40px;display:flex;flex-direction:column;gap:26px}.brand{display:flex;align-items:center;gap:11px;padding:0 8px}.brand-mark{width:34px;height:34px;border-radius:9px;background:linear-gradient(150deg,var(--accent),#ea580c);color:#fff;font-family:var(--font-serif);font-weight:600;display:grid;place-items:center;font-size:1.05rem;box-shadow:0 4px 12px -4px #c2410c8c;flex-shrink:0}.brand-text{line-height:1.2}.brand-text .name{font-family:var(--font-serif);font-weight:600;font-size:1.02rem;letter-spacing:-.01em}.brand-text .role{font-size:.72rem;color:var(--ink-mute);letter-spacing:.02em}.side-links{display:flex;flex-direction:column;gap:2px;margin:0 2px}.side-links a{font-size:.85rem;color:var(--ink-soft);padding:7px 10px;border-radius:var(--r-sm);transition:color var(--t-fast),background var(--t-fast)}.side-links a:hover{color:var(--ink);background:#00000008}.side-links a.active{color:var(--accent-ink);font-weight:600;background:var(--accent-wash)}.side-links a:focus-visible{outline:2px solid var(--accent);outline-offset:1px}nav.tree{display:flex;flex-direction:column;gap:4px}.group{margin-bottom:8px}.group-head{width:100%;display:flex;align-items:center;gap:8px;background:none;border:none;cursor:pointer;font:inherit;font-size:.7rem;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--ink-mute);padding:7px 8px;border-radius:var(--r-sm);transition:color var(--t-fast),background 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10px;border-radius:100px;letter-spacing:.01em}h1.post-title{font-family:var(--font-serif);font-weight:600;font-size:clamp(2.1rem,1.5rem + 2.4vw,3rem);line-height:1.08;letter-spacing:-.02em;color:var(--ink);margin-bottom:18px}.lede{font-family:var(--font-serif);font-size:1.24rem;line-height:1.55;color:var(--ink-soft);margin-bottom:30px}.rule{height:1px;background:var(--line);border:0;margin:0 0 36px}.post-nav{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin-top:56px;padding-top:32px;border-top:1px solid var(--line)}.post-nav a{border:1px solid var(--line);border-radius:var(--r-md);padding:14px 16px;background:var(--surface);transition:border-color var(--t-fast),transform var(--t-fast),box-shadow var(--t-fast)}.post-nav a:hover{border-color:var(--accent);transform:translateY(-2px);box-shadow:0 10px 24px -16px #c2410c80}.post-nav a:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.post-nav 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var(--accent);outline-offset:1px}.toc-aside{margin-top:28px;padding-top:20px;border-top:1px solid var(--line);font-size:.78rem;color:var(--ink-mute)}.toc-aside .share{display:flex;gap:8px;margin-top:10px}.toc-aside .share a{width:32px;height:32px;border:1px solid var(--line);border-radius:var(--r-sm);display:grid;place-items:center;color:var(--ink-mute);transition:border-color var(--t-fast),color var(--t-fast),transform var(--t-fast)}.toc-aside .share a:hover{border-color:var(--accent);color:var(--accent);transform:translateY(-2px)}.toc-aside .share a:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.sidebar::-webkit-scrollbar,.toc::-webkit-scrollbar{width:8px}.sidebar::-webkit-scrollbar-thumb,.toc::-webkit-scrollbar-thumb{background:var(--line);border-radius:8px}.overlay{display:none;position:fixed;inset:var(--header-h) 0 0 0;z-index:55;background:#14141266;backdrop-filter:blur(2px);opacity:0;transition:opacity 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#c2410c80}.post-card:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.post-card .pc-top{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin-bottom:8px}.post-card .pc-title{font-family:var(--font-serif);font-weight:600;font-size:1.3rem;line-height:1.2;letter-spacing:-.015em;color:var(--ink);margin-bottom:6px}.post-card:hover .pc-title{color:var(--accent-ink)}.post-card .pc-desc{font-size:.95rem;color:var(--ink-mute);line-height:1.5}.page-title{font-family:var(--font-serif);font-weight:600;font-size:clamp(2rem,1.4rem + 2vw,2.7rem);line-height:1.1;letter-spacing:-.02em;margin-bottom:24px}.notfound{display:grid;place-items:center;text-align:center;min-height:60vh;gap:14px}.notfound .code{font-family:var(--font-serif);font-size:clamp(3.5rem,2rem + 8vw,7rem);font-weight:600;line-height:1;color:var(--accent)}.notfound h1{font-family:var(--font-serif);font-size:1.6rem;font-weight:600}.notfound p{color:var(--ink-mute)}.btn-home{margin-top:8px;display:inline-block;border:1px solid var(--line);border-radius:var(--r-md);background:var(--surface);padding:11px 20px;font-size:.9rem;font-weight:600;color:var(--ink);transition:border-color var(--t-fast),color var(--t-fast),transform var(--t-fast)}.btn-home:hover{border-color:var(--accent);color:var(--accent);transform:translateY(-2px)}.btn-home:focus-visible{outline:2px solid var(--accent);outline-offset:2px}@media(max-width:1100px){.shell{grid-template-columns:var(--sidebar-w) minmax(0,1fr)}.toc{display:none}.article-wrap{padding:48px 36px 100px}}@media(max-width:780px){.shell,.shell.no-toc{grid-template-columns:1fr}.sidebar{position:fixed;top:var(--header-h);left:0;bottom:0;width:84vw;max-width:320px;z-index:60;transform:translate(-102%);transition:transform var(--t-mid);box-shadow:0 0 40px -10px #0000004d;height:calc(100vh - var(--header-h))}.sidebar.open{transform:translate(0)}.article-wrap{padding:32px 22px 90px}.post-nav{grid-template-columns:1fr}.post-nav .next{text-align:left}blockquote{font-size:1.12rem}.lede{font-size:1.1rem}}@media(max-width:400px){.article-wrap{padding:26px 16px 80px}}.nav-search{position:relative;display:flex;align-items:center;margin:4px 8px 14px}.nav-search-icon{position:absolute;left:11px;color:var(--ink-faint);pointer-events:none;transition:color var(--t-fast)}.nav-search input{width:100%;font-family:var(--font-sans);font-size:.86rem;color:var(--ink);background:var(--paper-2);border:1px solid var(--line);border-radius:var(--r-md);padding:8px 34px;appearance:none;-webkit-appearance:none;transition:border-color var(--t-fast),background var(--t-fast),box-shadow var(--t-fast)}.nav-search input::placeholder{color:var(--ink-faint)}.nav-search input::-webkit-search-cancel-button{-webkit-appearance:none}.nav-search input:hover{border-color:var(--ink-faint)}.nav-search input:focus{outline:none;background:var(--surface);border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-wash)}.nav-search input:focus+.nav-search-kbd{opacity:0}.nav-search:focus-within .nav-search-icon{color:var(--accent)}.nav-search-kbd{position:absolute;right:9px;font-family:var(--font-mono);font-size:.72rem;line-height:1;color:var(--ink-mute);background:var(--surface);border:1px solid var(--line);border-radius:var(--r-sm);padding:3px 6px;pointer-events:none;transition:opacity var(--t-fast)}.nav-search-empty{display:none;margin:-6px 10px 14px;font-size:.82rem;color:var(--ink-mute)}.nav-search-empty.show{display:block}.tree-link[hidden],.group[hidden]{display:none!important}@media(prefers-reduced-motion:reduce){.nav-search input,.nav-search-icon,.nav-search-kbd{transition:none}}