/* Palette: notebook paper, teal ink, highlighter yellow. Category colors live on .cat-* classes (CSP forbids inline styles). */
:root{--paper:#f4f6f1;--surface:#fff;--ink:#1d2b2a;--muted:#56645f;--line:#dde4dd;--accent:#0d6e58;--accent-strong:#0a5847;--soft:#e9f2ec;--mint:#e3f3ec;--marker:#ffe27a;--focus:#2a6fdb;--radius:12px}
.cat-practice{--cat:#3b7be0;--cat-bg:#e4edfc;--cat-fg:#1d4fa8}.cat-models{--cat:#8b5cf6;--cat-bg:#efe8fc;--cat-fg:#5a35a8}.cat-tools{--cat:#14a37f;--cat-bg:#d9f2ea;--cat-fg:#0b6650}.cat-editorial{--cat:#f0a020;--cat-bg:#fcefd2;--cat-fg:#7f4c00}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:2rem}body{margin:0;background:var(--paper);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Hiragino Kaku Gothic ProN","Noto Sans JP","Yu Gothic",Meiryo,sans-serif;font-size:15px;line-height:1.8;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}a:hover{color:var(--accent)}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid var(--focus);outline-offset:3px}button,input,select{font:inherit}button{cursor:pointer}h1,h2,h3,p{margin-top:0}h1,h2,h3{font-weight:700;line-height:1.5;letter-spacing:.01em}p{margin-bottom:1.2em}.wrap{width:min(1184px,calc(100% - 64px));margin-inline:auto}.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}.skip{position:absolute;top:-100px;left:12px;padding:8px;background:var(--ink);color:white;z-index:10}.skip:focus{top:10px}
/* Header */
.site-header{background:var(--surface);border-top:4px solid var(--accent);border-bottom:1px solid var(--line)}.header-inner{min-height:72px;display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{display:flex;align-items:center;gap:11px;font-size:18px;font-weight:800;letter-spacing:.01em;white-space:nowrap}.brand:hover{color:var(--ink)}.brand small{font-size:11px;border:1px solid var(--line);border-radius:4px;padding:1px 5px;margin-left:8px;color:var(--muted);font-weight:400;vertical-align:middle}.brand-symbol{display:flex;align-items:center;justify-content:center;width:36px;height:36px;border-radius:10px;background:var(--accent);color:#fff;font-family:Georgia,serif;font-style:italic;font-weight:700;font-size:21px;line-height:1;letter-spacing:-1px;padding-right:2px;transform:rotate(-4deg)}.brand-symbol span{color:var(--marker)}#main-nav{display:flex;gap:4px;align-items:center;font-size:14px;font-weight:700}#main-nav a{display:inline-flex;align-items:center;gap:6px;min-height:40px;padding:6px 14px;border-radius:999px}#main-nav a:hover{background:var(--soft);color:var(--ink)}#main-nav a[aria-current]{background:var(--mint);color:var(--accent-strong)}.search-link{border:1px solid var(--line);margin-left:6px}.search-link span{font-size:18px;line-height:1}.menu-toggle{display:none}
.eyebrow{font-family:Arial,sans-serif;font-size:12px;letter-spacing:.14em;font-weight:700;color:var(--accent);margin-bottom:4px}
/* Home hero: dotted notebook band with search */
.hero{background:radial-gradient(circle,rgba(13,110,88,.12) 1.2px,transparent 1.7px) 0 0/16px 16px,linear-gradient(180deg,var(--mint),var(--paper));border-bottom:1px solid var(--line)}.hero-inner{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,470px);gap:14px 48px;align-items:center;padding-block:34px 30px}.hero h1{display:inline;font-size:34px;line-height:1.4;letter-spacing:.02em;margin:0;background:linear-gradient(transparent 62%,var(--marker) 62%);padding:0 3px}.hero-summary{font-size:15px;color:var(--muted);margin:10px 0 0}.hero-search{display:flex;align-items:center;gap:8px;background:var(--surface);border:1px solid #bfcec4;border-radius:999px;padding:5px 5px 5px 18px}.hero-search:focus-within{outline:3px solid var(--focus);outline-offset:2px}.hero-search input{flex:1;min-width:0;border:0;background:transparent;color:var(--ink);font-size:15px;padding:7px 0}.hero-search input:focus{outline:none}.hero-search button{border:0;border-radius:999px;background:var(--accent);color:#fff;font-weight:700;min-height:40px;padding:6px 20px}.hero-search button:hover{background:var(--accent-strong)}.hero-cats{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px}.hero-cats .cat-chip{min-height:36px;padding:5px 14px;font-size:13px;background:var(--surface);border:1px solid var(--line)}
/* Category chip: dot + name, always with text so color is never the only cue */
.cat-chip{display:inline-flex;align-items:center;gap:6px;min-height:24px;padding:2px 10px;border-radius:999px;background:var(--cat-bg,var(--mint));color:var(--cat-fg,var(--accent-strong));font-size:12px;font-weight:700;line-height:1.5;white-space:nowrap}.cat-chip::before{content:"";flex:none;width:7px;height:7px;border-radius:50%;background:var(--cat,var(--accent))}a.cat-chip:hover{color:var(--cat-fg,var(--accent-strong));text-decoration:underline;text-underline-offset:3px}
/* Section headings with a highlighter stroke */
.latest{padding-top:26px}.section-heading{display:flex;justify-content:space-between;align-items:flex-end;gap:16px;margin-bottom:14px}.section-heading h2{display:inline;font-size:22px;margin:0;padding:0 3px;background:linear-gradient(transparent 62%,var(--marker) 62%)}.section-heading>a{font-size:14px;font-weight:700;color:var(--accent);padding:8px 0;white-space:nowrap}
/* Compact list cards: image + category + date + title */
.card-list{display:grid;gap:10px}.card-list>.empty-state{grid-column:1/-1}.article-row{display:grid;grid-template-columns:200px minmax(0,1fr);gap:16px;align-items:start;padding:12px;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);transition:border-color .15s,box-shadow .15s}.article-row:hover{border-color:var(--cat,var(--accent));box-shadow:0 4px 14px rgba(29,43,42,.07)}.article-thumbnail{display:block;min-width:0}.article-thumbnail img{display:block;width:100%;height:auto;aspect-ratio:16/9;object-fit:contain;border-radius:8px;border:1px solid var(--line);background:var(--cat-bg,var(--soft))}.thumb-label{display:inline-block;margin-top:4px;padding:0 6px;border-radius:4px;font-size:11px;line-height:1.6;color:#4a5652;background:#e8ece9}.thumb-label.is-official{color:#1d4fa8;background:#e4edfc}.thumb-label.is-concept{color:#7f4c00;background:#fcefd2}.card-placeholder{display:grid;place-items:center;aspect-ratio:16/9;border-radius:8px;border:1px solid var(--line);background:radial-gradient(circle,rgba(0,0,0,.07) 1px,transparent 1.5px) 0 0/10px 10px,var(--cat-bg,var(--mint));color:var(--cat-fg,var(--accent-strong));font-size:13px;font-weight:800;text-align:center;padding:4px}.article-card-content{min-width:0}.article-row .meta{display:flex;flex-wrap:wrap;align-items:center;gap:4px 10px;margin:0 0 4px;font-size:12px;line-height:1.5;color:var(--muted)}.article-row .meta time{font-family:Arial,sans-serif;letter-spacing:.03em}.article-row h2{font-size:18px;line-height:1.55;margin:0;overflow-wrap:anywhere}.article-row h2 a:hover{color:inherit;text-decoration:underline;text-underline-offset:4px;text-decoration-color:var(--cat,var(--accent))}.article-row p{font-size:13px;line-height:1.75;color:var(--muted);margin:6px 0 0;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
/* Category tiles */
.categories-section{padding-block:36px 56px}.category-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:14px}.category-card{display:block;background:var(--surface);border:1px solid var(--line);border-top:5px solid var(--cat,var(--accent));border-radius:var(--radius);padding:16px 18px;transition:box-shadow .15s}.category-card:hover{color:inherit;box-shadow:0 4px 14px rgba(29,43,42,.08)}.category-number{display:inline-grid;place-items:center;width:30px;height:30px;border-radius:50%;background:var(--cat-bg);color:var(--cat-fg);font-family:Georgia,serif;font-style:italic;font-weight:700;font-size:13px}.category-card h3{font-size:17px;margin:10px 0 4px;display:flex;justify-content:space-between;gap:8px}.category-card h3 span{color:var(--cat-fg);font-weight:400}.category-card p{font-size:13px;line-height:1.8;color:var(--muted);margin-bottom:10px}.category-card small{display:inline-block;font-size:12px;font-weight:700;color:var(--cat-fg);background:var(--cat-bg);border-radius:999px;padding:1px 10px}
/* Footer */
.site-footer{background:#16302b;color:#e8f0ec;margin-top:24px}.footer-inner{display:grid;grid-template-columns:1fr 1fr;gap:20px;padding-block:30px 22px}.footer-brand{font-size:16px;font-weight:800}.footer-brand:hover,.site-footer nav a:hover{color:var(--marker)}.site-footer p{font-size:13px;color:#a9c2b9;margin:6px 0 0}.site-footer nav{display:flex;gap:8px 22px;justify-content:flex-end;align-items:flex-start;flex-wrap:wrap;font-size:13px}.site-footer nav a{display:inline-block;min-width:32px;padding:4px 2px;text-align:center}.site-footer small{grid-column:1/-1;font-family:Arial,sans-serif;font-size:12px;color:#a9c2b9}
/* List and info pages */
.page-heading{padding-top:28px;padding-bottom:14px}.page-heading h1{font-size:30px;line-height:1.4;margin-bottom:6px}.page-heading[class*="cat-"] h1{border-left:6px solid var(--cat);padding-left:12px}.page-heading[class*="cat-"] .eyebrow{color:var(--cat-fg)}.page-heading>p:last-child{color:var(--muted);font-size:14px;margin:0}.narrow-list{padding-bottom:56px;min-height:300px}.count{color:var(--muted);font-size:13px;margin:0 0 10px}.empty-state{background:var(--surface);border:1px dashed #b9c7bd;border-radius:var(--radius);padding:28px 24px}.empty-state h2{font-size:19px}.empty-state p{color:var(--muted)}.empty-state a,.not-found a{color:var(--accent);text-decoration:underline;text-underline-offset:6px;font-size:14px}.categories-page{padding-bottom:64px;min-height:300px}
/* Article page */
.article-top{max-width:930px;padding-top:24px;padding-bottom:28px;border-bottom:1px solid var(--line)}.back-link{display:inline-block;color:var(--muted);font-size:13px;margin-bottom:18px;padding-block:4px}.article-top .meta{display:flex;flex-wrap:wrap;align-items:center;gap:6px 12px;max-width:760px;font-size:12px;line-height:1.6;color:var(--muted);margin-bottom:12px}.article-top .meta time{font-family:Arial,sans-serif;letter-spacing:.04em}.article-top h1{font-size:32px;line-height:1.55;font-weight:800;max-width:860px;margin-bottom:12px}.article-top .article-eyecatch{margin:22px 0 0}.article-eyecatch img{border-radius:var(--radius);border:1px solid var(--line)}.article-deck{max-width:780px;color:var(--muted);font-size:16px;line-height:1.9}.article-dates{display:flex;flex-wrap:wrap;gap:6px 18px;font-size:13px;color:var(--muted);margin-top:16px}.reading-layout{max-width:1100px;display:grid;grid-template-columns:240px minmax(0,700px);gap:56px;padding-top:36px;padding-bottom:64px;justify-content:center}.toc{font-size:13px}.toc details{position:sticky;top:24px;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:14px 16px}.toc summary{font-size:14px;font-weight:700;cursor:pointer;padding:2px 0 8px;border-bottom:1px solid var(--line)}.toc ol{padding-left:20px;color:var(--muted);line-height:1.7;margin-bottom:0}.toc li{padding:5px 0 5px 2px}.toc a:hover{color:var(--accent);text-decoration:underline}.prose{font-size:16px;line-height:2.05;min-width:0;overflow-wrap:anywhere}.prose p{margin-bottom:1.6em}.prose h2{font-size:22px;line-height:1.55;border-left:5px solid var(--accent);background:linear-gradient(90deg,var(--mint),transparent 75%);padding:6px 10px 6px 12px;border-radius:0 8px 8px 0;margin-top:44px;margin-bottom:20px}.prose h3{font-size:18px;margin-top:30px;margin-bottom:12px}.prose ul{padding-left:1.5em}.prose a{color:var(--accent);text-decoration:underline;text-underline-offset:4px}.prose blockquote{margin:26px 0;padding:16px 20px;border-left:4px solid var(--accent);border-radius:0 10px 10px 0;background:var(--mint);color:var(--ink)}.prose blockquote p{margin-bottom:.8em}.prose blockquote p:last-child{margin-bottom:0}.prose pre{overflow:auto;padding:18px;background:#eef3ef;border-radius:8px;font-size:13px}.prose img{max-width:100%;height:auto}.prose table{display:block;overflow:auto;border-collapse:collapse;max-width:100%}.prose td,.prose th{padding:8px;border:1px solid var(--line)}.source-box{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:22px 24px;margin-top:40px;font-size:13px}.source-box h2{border:0;background:none;font-size:16px;margin:0 0 10px;padding:0}.source-box p{margin-bottom:0}.article-tags{display:flex;flex-wrap:wrap;gap:8px;margin:26px 0 30px;font-size:13px}.article-tags a{display:inline-flex;align-items:center;min-height:32px;padding:3px 12px;border-radius:999px;background:var(--surface);border:1px solid var(--line);text-decoration:none}.article-tags a:hover{border-color:var(--accent)}
.about-layout{display:grid;grid-template-columns:minmax(0,690px) 1fr;gap:80px;padding-bottom:80px}.about-aside{border-top:5px solid var(--marker);padding-top:26px}.about-aside>p{font-family:"Yu Mincho",serif;font-size:30px;line-height:1.9;margin-top:30px}.about-aside>span:last-child{font-size:13px;color:var(--muted)}
.search-area{padding-bottom:64px;min-height:400px}#search-form{max-width:760px}#search-form label{display:block;font-size:13px;font-weight:700;margin-bottom:6px}.search-input-row{display:flex;gap:8px;margin-bottom:16px}#query{min-width:0;width:100%;border:1px solid #b9c7bd;background:#fff;padding:11px 18px;border-radius:999px;color:var(--ink)}.search-input-row button{border:0;border-radius:999px;background:var(--accent);color:white;font-weight:700;padding:10px 24px;white-space:nowrap}#category-filter{padding:9px 36px 9px 14px;border:1px solid #b9c7bd;border-radius:999px;background:white;color:var(--ink);min-height:42px}#search-status{font-size:13px;color:var(--muted);margin:20px 0 12px}
.not-found{padding:90px 0 120px;min-height:480px}.not-found h1{font-size:30px}.not-found p{color:var(--muted)}.not-found a{display:inline-block;margin-right:30px;margin-top:20px}
@media(min-width:1001px){.card-list{grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}}
@media(max-width:1000px){.wrap{width:calc(100% - 48px)}.hero-inner{grid-template-columns:1fr;gap:16px}.reading-layout{gap:32px;grid-template-columns:190px minmax(0,1fr)}.about-layout{gap:45px}.article-row{grid-template-columns:180px minmax(0,1fr)}}
@media(max-width:760px){.wrap{width:calc(100% - 32px)}.header-inner{min-height:60px;gap:8px 12px;flex-wrap:wrap;position:relative;padding-block:8px}.brand{font-size:17px;gap:9px}.brand-symbol{width:32px;height:32px;font-size:19px;border-radius:9px}.menu-toggle{display:inline-flex;align-items:center;gap:6px;min-height:40px;border:1px solid var(--line);border-radius:999px;background:var(--surface);padding:4px 14px;font-size:14px;font-weight:700;color:var(--ink)}#main-nav{display:flex;width:100%;flex-wrap:wrap;border-top:1px solid var(--line);padding:10px 0 4px;gap:6px}.js #main-nav{display:none}.js #main-nav.is-open{display:flex}#main-nav .search-link{margin-left:0}.eyebrow{font-size:11px;margin-bottom:2px}.hero-inner{padding-block:16px 16px;gap:10px}.hero h1{font-size:22px}.hero-summary{font-size:14px;margin-top:6px}.hero-search{padding-left:14px}.hero-search input{font-size:16px;padding:4px 0}.hero-search button{min-height:36px;padding:4px 16px}.hero-cats{margin-top:10px;gap:6px}.hero-cats .cat-chip{min-height:32px;padding:3px 12px}.latest{padding-top:16px}.section-heading{margin-bottom:10px}.section-heading h2{font-size:19px}.section-heading>a{font-size:13px}.card-list{gap:8px}.article-row{grid-template-columns:112px minmax(0,1fr);gap:12px;padding:10px}.article-row h2{font-size:16px;line-height:1.5}.article-row p,.article-row .read-time{display:none}.categories-section{padding-block:28px 40px}.category-grid{grid-template-columns:1fr 1fr;gap:10px}.category-card{padding:12px 14px}.category-card h3{font-size:15px}.category-card p{font-size:13px}.footer-inner{grid-template-columns:1fr;gap:12px;padding-block:24px 18px}.site-footer nav{justify-content:flex-start;gap:4px 20px}.page-heading{padding-top:18px;padding-bottom:10px}.page-heading h1{font-size:24px;margin-bottom:2px}.page-heading>p:last-child{font-size:13px}.narrow-list{padding-bottom:40px}.count{margin-bottom:8px}.categories-page{padding-bottom:44px}.article-top{padding-top:16px;padding-bottom:22px}.article-top .back-link{margin-bottom:12px}.article-top h1{font-size:24px;line-height:1.6}.article-deck{font-size:15px}.article-dates{font-size:12px;gap:4px 14px}.reading-layout{grid-template-columns:1fr;gap:22px;padding-top:20px;padding-bottom:32px}.toc details{position:static}.prose{font-size:16px;line-height:2}.prose h2{font-size:20px;margin-top:36px}.prose h3{font-size:17px}.source-box{padding:18px}.about-layout{grid-template-columns:1fr;gap:30px;padding-bottom:44px}.about-aside{padding-top:20px}.about-aside>p{font-size:26px;margin-top:16px}.search-input-row button{padding:10px 18px}.search-area{padding-bottom:40px}.not-found{padding-top:60px;padding-bottom:60px}.not-found h1{font-size:24px}.not-found p{font-size:14px}}
@media(max-width:360px){.wrap{width:calc(100% - 24px)}.article-row{grid-template-columns:96px minmax(0,1fr);grid-template-areas:"meta meta" "thumb title";gap:6px 10px;padding:8px 10px 10px}.article-card-content{display:contents}.article-row .meta{grid-area:meta;margin:0}.article-row .article-thumbnail,.article-row .card-placeholder{grid-area:thumb}.article-row h2{grid-area:title}.category-grid{grid-template-columns:1fr}.brand{font-size:16px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}@media print{.site-header,.site-footer,.toc,.article-tags,.back-link{display:none}.wrap{width:100%;max-width:none}.reading-layout{display:block}.prose{font-size:11pt}.article-top h1{font-size:25pt}body{background:white;color:black}}

.review-notice{font-size:12px;color:var(--muted);padding-top:14px;margin-bottom:0}.draft-label{color:var(--accent)}.article-figure{margin:28px 0 24px;padding:18px;border:1px solid var(--line);background:#fff}.prose .diagram-preview{display:block;margin:auto;max-height:360px;width:auto;max-width:100%;height:auto}.diagram-details{margin-top:18px}.diagram-details summary{cursor:pointer;font-size:13px;font-weight:650;color:var(--accent);padding-block:8px}.prose .diagram-hint{font-size:12px;color:var(--muted);margin:8px 0}.diagram-scroll{max-height:520px;overflow:auto;overscroll-behavior:contain;border:1px solid var(--line);background:#fff}.prose .diagram-scroll img{display:block;width:360px;max-width:none;height:auto}.diagram-details>a{font-size:12px;display:inline-block;margin-top:12px}@media(max-width:760px){.article-figure{padding:12px}.prose .diagram-preview{max-height:300px}.diagram-scroll{max-height:460px}}

.diagram-scroll:focus-visible{outline:3px solid var(--accent);outline-offset:3px}.prose .article-figure+p{font-size:12px;line-height:1.9;color:var(--muted)}

.article-eyecatch{max-width:800px;margin:0 0 28px}.article-eyecatch img{display:block;width:100%;height:auto;aspect-ratio:16/9}.article-eyecatch figcaption{margin-top:8px;font-size:12px;line-height:1.6;color:var(--muted)}.article-thumbnail.eyecatch-thumbnail img{height:auto;aspect-ratio:16/9;object-fit:contain;object-position:center}

/* Full-height body diagrams keep their explanation readable on phones. */
.prose .article-figure{padding:0;border:0;background:transparent}.prose .diagram-preview{display:block;width:100%;height:auto;max-height:none;max-width:100%;margin:0}.prose .diagram-preview picture{display:block}.prose .article-figure+p{font-size:14px;line-height:1.9}.prose .diagram-scroll img{width:720px}.prose .diagram-details summary{font-size:14px}@media(max-width:760px){.prose .diagram-preview{max-height:none;width:100%}.prose .article-figure{margin-inline:-10px}}

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/* Licensed official screenshots: preserve the source pixels and allow readable zoom. */
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