:root{
  --deep:#070a12;--deep2:#0d1220;--paper:#f5efe4;--paper2:#fffaf1;--ink:#18202f;--muted:#657084;--gold:#b9965d;--gold2:#d8bf83;--line:rgba(24,32,47,.15);--deepLine:rgba(255,255,255,.16);--blue:#385f9f;--green:#4e8260;--violet:#725a86;--amber:#9b7443;--ivory:#f7f1e6;--serif:"Yu Mincho","Hiragino Mincho ProN","Noto Serif JP",serif;--sans:Inter,"Hiragino Sans","Yu Gothic","Noto Sans JP",system-ui,sans-serif;--mono:"SFMono-Regular",Consolas,Menlo,monospace;--max:1180px;--article:920px}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:var(--sans);color:var(--ink);background:var(--paper);line-height:1.84;letter-spacing:.015em}a{color:inherit;text-decoration:none}.topbar{position:sticky;top:0;z-index:50;background:rgba(7,10,18,.82);color:var(--ivory);backdrop-filter:blur(18px);border-bottom:1px solid var(--deepLine)}.topbar-inner{max-width:var(--max);margin:0 auto;padding:13px 22px;display:flex;justify-content:space-between;gap:24px;align-items:center}.brand{font-family:var(--serif);letter-spacing:.12em;white-space:nowrap;font-size:18px}.brand small{display:block;font-family:var(--mono);font-size:10px;letter-spacing:.13em;color:var(--gold2);margin-top:-2px}.nav{display:flex;gap:20px;font-size:13px;color:rgba(247,241,230,.78);flex-wrap:wrap}.nav a{border-bottom:1px solid rgba(216,191,131,.28);padding-bottom:3px}.nav a:hover{color:white}.hero{min-height:74vh;color:var(--ivory);background:linear-gradient(90deg,rgba(7,10,18,.58),rgba(7,10,18,.30),rgba(7,10,18,.82)),url('hero-main.png') center/cover no-repeat, var(--deep);position:relative;overflow:hidden;border-bottom:1px solid rgba(255,255,255,.16)}.hero::after{content:"";position:absolute;inset:0;background:linear-gradient(to bottom,transparent 70%,rgba(245,239,228,.98));pointer-events:none}.hero-inner{position:relative;z-index:1;max-width:var(--max);margin:0 auto;padding:118px 22px 124px;display:grid;grid-template-columns:.56fr 1fr;align-items:center;gap:42px}.hero-mark{min-height:320px;border-left:1px solid rgba(216,191,131,.38);border-bottom:1px solid rgba(216,191,131,.28);border-radius:0 0 0 34px;position:relative;opacity:.9}.hero-mark::before,.hero-mark::after{content:"";position:absolute;border:1px solid rgba(216,191,131,.26);border-radius:50%}.hero-mark::before{width:280px;height:280px;left:-70px;top:-20px}.hero-mark::after{width:150px;height:150px;left:78px;top:82px}.eyebrow{font-family:var(--mono);font-size:12px;letter-spacing:.16em;text-transform:uppercase;color:var(--gold2);margin-bottom:20px}h1{margin:0 0 22px;font-family:var(--serif);font-weight:600;font-size:clamp(42px,6vw,88px);line-height:1.08;letter-spacing:-.06em}.lead{max-width:760px;color:rgba(247,241,230,.90);font-size:clamp(16px,1.45vw,20px);line-height:2}.actions{display:flex;gap:14px;flex-wrap:wrap;margin-top:32px}.button{display:inline-flex;align-items:center;justify-content:center;min-width:190px;padding:12px 20px;border-radius:2px;border:1px solid rgba(247,241,230,.42);font-weight:700;letter-spacing:.04em}.button.primary{background:linear-gradient(135deg,var(--gold),#d9c184);color:#121827;border:none}.section{padding:76px 22px;position:relative}.section:nth-of-type(even){background:var(--paper2)}.inner{max-width:var(--max);margin:0 auto}.section-grid{display:grid;grid-template-columns:92px 1fr;gap:32px;align-items:start}.num{font-family:var(--serif);font-size:42px;line-height:1;color:var(--gold);position:relative}.num::after{content:"";display:block;width:1px;height:84px;background:rgba(185,150,93,.42);margin:20px auto 0 18px}h2{margin:0 0 20px;font-family:var(--serif);font-size:clamp(28px,4vw,52px);line-height:1.22;letter-spacing:-.045em;font-weight:600}.body{max-width:850px;color:#333d4e;font-size:16px}.cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:30px}.card{border:1px solid var(--line);background:rgba(255,255,255,.46);border-radius:12px;padding:24px;min-height:220px;position:relative;overflow:hidden}.card::before{content:"";width:44px;height:44px;border-radius:50%;display:block;margin-bottom:18px;background:radial-gradient(circle,rgba(255,255,255,.72),transparent 38%),linear-gradient(135deg,rgba(185,150,93,.85),rgba(56,95,159,.22));border:1px solid rgba(24,32,47,.14)}.card h3{margin:0 0 12px;font-family:var(--serif);font-size:22px;line-height:1.45}.card p{margin:0;color:#4f596b;font-size:14px}.route{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;margin-top:28px}.phase{background:rgba(255,255,255,.54);border:1px solid var(--line);border-radius:12px;padding:22px;min-height:210px}.phase .tag{display:inline-flex;width:48px;height:48px;border-radius:50%;align-items:center;justify-content:center;color:white;font-family:var(--mono);margin-bottom:14px}.phase:nth-child(1) .tag{background:var(--blue)}.phase:nth-child(2) .tag{background:var(--green)}.phase:nth-child(3) .tag{background:var(--violet)}.phase:nth-child(4) .tag{background:var(--amber)}.phase h3{margin:0 0 12px;font-family:var(--serif);font-size:20px;line-height:1.45}.phase p{color:#4f596b;font-size:13px;margin:0}.library{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;margin-top:30px}.shelf{border:1px solid var(--line);border-radius:14px;background:rgba(255,255,255,.56);overflow:hidden}.shelf-head{padding:18px 20px;background:rgba(24,32,47,.045);border-bottom:1px solid var(--line);display:flex;justify-content:space-between;gap:18px;align-items:baseline}.shelf-head h3{margin:0;font-family:var(--serif);font-size:22px;line-height:1.35}.shelf-head span{font-family:var(--mono);font-size:11px;color:var(--gold);letter-spacing:.08em;white-space:nowrap}.article-list{list-style:none;padding:0;margin:0}.article-list li{padding:13px 20px;border-bottom:1px solid rgba(24,32,47,.09);display:flex;justify-content:space-between;gap:18px;color:#30394a;font-size:14px}.article-list li:last-child{border-bottom:none}.status{font-family:var(--mono);font-size:11px;color:#7a8392;white-space:nowrap}.status.live{color:var(--blue)}.status.plan{color:var(--amber)}.notes-layout{display:grid;grid-template-columns:.92fr 1.08fr;gap:18px;margin-top:30px}.feature-note{border:1px solid rgba(24,32,47,.18);background:linear-gradient(135deg,rgba(7,10,18,.94),rgba(18,24,39,.9));color:var(--ivory);border-radius:16px;padding:28px;min-height:360px;position:relative;overflow:hidden}.feature-note::after{content:"";position:absolute;width:280px;height:280px;right:-90px;bottom:-120px;border-radius:50%;border:1px solid rgba(216,191,131,.26)}.feature-note h3{font-family:var(--serif);font-size:30px;line-height:1.35;margin:0 0 18px}.feature-note p{color:rgba(247,241,230,.72);margin:0}.note-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.note-card{border:1px solid var(--line);background:rgba(255,255,255,.58);border-radius:14px;padding:20px;min-height:170px}.note-card h3{font-family:var(--serif);font-size:21px;line-height:1.4;margin:0 0 10px}.note-card p{color:#4f596b;font-size:13px;margin:0}.quote-box{margin-top:32px;border:1px solid rgba(185,150,93,.34);background:rgba(255,255,255,.42);border-radius:10px;padding:24px 26px;display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:0;position:relative}.quote-box::before,.quote-box::after{position:absolute;font-family:var(--serif);color:var(--gold);font-size:42px;opacity:.55}.quote-box::before{content:"“";left:16px;top:6px}.quote-box::after{content:"”";right:16px;bottom:-8px}.quote-line{padding:12px 18px;border-right:1px solid rgba(24,32,47,.12);color:#24324b;font-family:var(--serif);font-size:16px;line-height:1.75}.quote-line:last-child{border-right:none}.page-hero{color:var(--ivory);background:linear-gradient(90deg,rgba(7,10,18,.78),rgba(7,10,18,.62)),url('hero-main.png') center/cover no-repeat,var(--deep);padding:90px 22px 74px;border-bottom:1px solid var(--deepLine)}.page-hero .inner{max-width:var(--article)}.page-hero h1{font-size:clamp(38px,5vw,72px)}.meta{display:flex;flex-wrap:wrap;gap:8px;margin:20px 0 0}.meta span{font-family:var(--mono);font-size:11px;color:rgba(247,241,230,.78);border:1px solid rgba(247,241,230,.22);padding:4px 8px;border-radius:999px}.article-wrap{max-width:var(--article);margin:0 auto;padding:70px 22px 90px}.note-content{font-size:16px;color:#252f42}.note-content h2{font-size:clamp(26px,3vw,44px);padding-top:34px;border-top:1px solid rgba(24,32,47,.13);margin-top:54px}.note-content h3{font-family:var(--serif);font-size:26px;line-height:1.45;margin:44px 0 12px;color:#1f2937}.note-content h4{font-size:18px;margin:30px 0 8px;color:#24324b}.note-content p{margin:0 0 1.1em}.note-content blockquote{margin:1.2em 0;padding:14px 18px;border-left:4px solid var(--gold);background:rgba(255,255,255,.48);color:#344052}.note-content ul{padding-left:1.35em}.note-content li{margin:.35em 0}.math-block{overflow-x:auto;background:rgba(255,255,255,.56);border:1px solid rgba(24,32,47,.12);border-radius:12px;padding:18px;margin:18px 0;color:#172033}.note-content table{width:100%;border-collapse:collapse;margin:22px 0;background:rgba(255,255,255,.54);border:1px solid var(--line);font-size:14px}.note-content td,.note-content th{border:1px solid rgba(24,32,47,.12);padding:10px 12px;vertical-align:top}.note-content tr:first-child td{font-weight:700;background:rgba(24,32,47,.045)}.toc{background:rgba(255,255,255,.55);border:1px solid var(--line);border-radius:14px;padding:18px 20px;margin-bottom:34px}.toc b{font-family:var(--serif);font-size:18px}.toc a{display:block;color:#344052;font-size:14px;margin:4px 0}.page-nav{display:flex;gap:10px;flex-wrap:wrap;margin:26px 0}.page-nav a{border:1px solid var(--line);background:rgba(255,255,255,.56);padding:8px 12px;border-radius:999px;font-size:13px}.footer{padding:58px 22px;background:var(--deep);color:rgba(247,241,230,.65);border-top:1px solid var(--deepLine)}.footer .inner{display:flex;justify-content:space-between;gap:24px;flex-wrap:wrap;font-size:13px}.raw-note{white-space:pre-wrap;font-family:var(--sans);line-height:1.84}.notice{border:1px solid rgba(185,150,93,.38);background:rgba(255,255,255,.48);border-radius:14px;padding:16px 18px;margin:22px 0;color:#3b4350}
@media(max-width:980px){.hero-inner,.section-grid,.cards,.route,.library,.notes-layout,.note-grid,.quote-box{grid-template-columns:1fr}.hero-mark{display:none}.quote-line{border-right:none;border-bottom:1px solid rgba(24,32,47,.12)}.quote-line:last-child{border-bottom:none}.nav{gap:12px}.topbar-inner{align-items:flex-start;flex-direction:column}.hero-inner{padding-top:86px}.brand{white-space:normal}.button{width:100%}}

.overview-list{display:grid;gap:12px;margin:26px 0 0;padding:0;list-style:none}.overview-list li{border:1px solid var(--line);background:rgba(255,255,255,.48);border-radius:12px;padding:16px 18px}.overview-list b{font-family:var(--serif);font-size:19px;color:#1f2937}.overview-list span{display:block;color:#4f596b;font-size:14px;margin-top:4px}.directory{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;margin-top:28px}.directory .shelf{min-height:100%}.page-nav a[aria-disabled="true"],.disabled-link{opacity:.55;pointer-events:none}.prevnext{display:flex;justify-content:space-between;gap:14px;margin-top:54px;padding-top:24px;border-top:1px solid rgba(24,32,47,.14)}.prevnext a{border:1px solid var(--line);border-radius:999px;padding:10px 14px;background:rgba(255,255,255,.46);font-size:13px}.note-content .public-intro{border:1px solid rgba(185,150,93,.28);background:rgba(255,255,255,.46);border-radius:14px;padding:18px 20px;margin:0 0 34px;color:#344052}.toc.compact a{display:inline-block;margin:4px 10px 4px 0}.article-list a{text-decoration:none;color:#24324b}.article-list a:hover{text-decoration:underline}.topbar .nav a.active{color:#fff;border-bottom-color:var(--gold2)}
@media(max-width:980px){.directory{grid-template-columns:1fr}}

.directory{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;margin-top:30px}.overview-list{display:grid;gap:18px;margin:0;padding:0;list-style:none}.overview-list>li{border:1px solid var(--line);background:rgba(255,255,255,.52);border-radius:14px;padding:20px}.overview-list b{display:block;font-family:var(--serif);font-size:22px;margin-bottom:8px}.overview-list span{display:block;color:#3f485a}.overview-list ul{margin:.4em 0 0;padding-left:1.3em}.overview-list li li{margin:.22em 0}.overview-list .phase-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:12px}.overview-list .phase-list div{border:1px solid rgba(24,32,47,.12);background:rgba(255,255,255,.42);border-radius:10px;padding:12px}.overview-list .phase-list strong{display:block;margin-bottom:4px;color:#25324a}
@media(max-width:980px){.directory,.overview-list .phase-list{grid-template-columns:1fr}}

/* v5: hero image is assets/hero-main.png; URL is relative to assets/style.css */