/* ============================================================
   New Realities Corporation — AI News Briefing
   Brand stylesheet (v1.0)
   ============================================================ */

:root{
  --brand-blue:#2B4C7E;
  --brand-blue-dark:#1f3a62;
  --brand-sub:#A8B8C8;
  --accent-bg:#F0F4F9;
  --ink:#1a1f2e;
  --ink-sub:#5b6573;
  --ink-mute:#8a93a0;
  --rule:#e3e8ef;
  --rule-soft:#eef2f7;
  --rule-strong:#1a1f2e;
  --new:#c0392b;
  --fresh:#2B4C7E;
  --background:#8a93a0;
  --risk:#b9531c;
  --new-green:#0a8f6b;
  --accent-orange:#e08e3a;
  --accent-purple:#7651b5;
  --accent-teal:#1c8a8a;
  --accent-rose:#b94278;
}

*{box-sizing:border-box}

html,body{
  margin:0;padding:0;background:#fff;color:var(--ink);
  font-family:"Noto Sans JP","Inter",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif;
  font-weight:400;line-height:1.75;
  -webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;
}

a{color:var(--brand-blue);text-decoration:none}
a:hover{text-decoration:underline}

.container{max-width:1100px;margin:0 auto;padding:0 24px}

/* ============================================================
   Top utility bar (Newsroom style)
   ============================================================ */
.util-bar{background:var(--rule-strong);color:#fff;font-family:"JetBrains Mono",monospace;font-size:11.5px;letter-spacing:0.08em}
.util-inner{display:flex;justify-content:space-between;align-items:center;padding:7px 24px}
.util-inner .ticker{display:flex;gap:18px;color:rgba(255,255,255,0.7)}
.util-inner .ticker b{color:#fff;font-weight:600}

/* ============================================================
   Masthead
   ============================================================ */
.masthead{padding:22px 0 14px;border-bottom:3px double var(--rule-strong)}
.masthead-inner{display:flex;align-items:center;justify-content:space-between;gap:18px}
.brand-line{display:flex;align-items:center;gap:14px}
.brand-mark{width:42px;height:42px}
.brand-text{display:flex;flex-direction:column;line-height:1.1}
.brand-text .pub{font-family:"Inter",sans-serif;font-size:11px;letter-spacing:0.25em;text-transform:uppercase;color:var(--ink-mute);font-weight:600}
.brand-text .title{font-family:"Noto Serif JP","Inter",serif;font-size:30px;font-weight:700;color:var(--ink);letter-spacing:-0.005em;margin-top:2px}
.masthead-meta{font-family:"Inter",sans-serif;font-size:12.5px;color:var(--ink-sub);text-align:right;line-height:1.65}
.masthead-meta .vol{font-weight:600;color:var(--ink)}

/* ============================================================
   Navigation
   ============================================================ */
.site-nav-wrap{border-bottom:1px solid var(--rule);padding:10px 0;background:#fff;position:sticky;top:0;z-index:30}
.site-nav{display:flex;justify-content:center;gap:30px;flex-wrap:wrap}
.site-nav a{font-family:"Inter","Noto Sans JP",sans-serif;font-size:13px;font-weight:600;color:var(--ink);letter-spacing:0.08em;text-transform:uppercase}
.site-nav a.is-active{color:var(--brand-blue)}
.site-nav a:hover{color:var(--brand-blue);text-decoration:none}

/* ============================================================
   Page layout: Main column + Sticky Arena sidebar
   ページ全体を2カラムに。Arena は右に常駐し全セクションに追従。
   ============================================================ */
.page-grid{display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:36px;padding:28px 0 36px;align-items:start}
.page-main{min-width:0}
.page-aside{position:sticky;top:84px;align-self:start;display:flex;flex-direction:column;gap:12px}
.page-aside .arena-snap{margin-top:0}

@media (max-width:880px){
  .page-grid{grid-template-columns:1fr;gap:20px}
  .page-aside{position:static}
}

/* ============================================================
   Today's Topics (main column 上部)
   ============================================================ */
.topics-head{display:flex;align-items:baseline;justify-content:space-between;gap:14px;margin-bottom:14px;padding-bottom:10px;border-bottom:2px solid var(--rule-strong)}
.topics-head .label{font-family:"Inter",sans-serif;font-size:11.5px;font-weight:800;letter-spacing:0.22em;text-transform:uppercase;color:var(--brand-blue)}
.topics-head .title{font-family:"Noto Serif JP","Inter",serif;font-size:26px;font-weight:700;color:var(--ink);letter-spacing:-0.005em;line-height:1.2;margin:0}
.topics-head .meta{font-family:"Inter",sans-serif;font-size:12px;color:var(--ink-mute);letter-spacing:0.05em}

/* 4本を2x2でコンパクトに */
.topics-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px;margin-bottom:0}
.topic-card{display:flex;align-items:flex-start;gap:10px;padding:12px 14px;background:#fff;border:1px solid var(--rule);border-radius:8px;color:var(--ink);transition:all 0.12s ease}
.topic-card:hover{text-decoration:none;border-color:var(--brand-blue);transform:translateY(-1px);box-shadow:0 3px 10px rgba(43,76,126,0.06)}
.topic-card .badge{margin:1px 0 0 0;flex-shrink:0}
.topic-card-body{display:flex;flex-direction:column;gap:3px;min-width:0}
.topic-card-date{font-family:"Inter",sans-serif;font-size:11px;color:var(--ink-mute);letter-spacing:0.05em}
.topic-card-title{font-family:"Noto Sans JP","Inter",sans-serif;font-size:13.5px;font-weight:700;color:var(--ink);line-height:1.5;margin:0}

/* legacy .front (kept for backwards compatibility in archive pages) */
.front{display:grid;grid-template-columns:2.4fr 1fr;gap:36px;padding:28px 0 8px;align-items:start}
.front-aside{display:flex;flex-direction:column;gap:8px;position:sticky;top:80px;align-self:start}
.front-aside .arena-snap{margin-top:0}
@media (max-width:880px){
  .front{grid-template-columns:1fr;gap:24px}
  .front-aside{position:static}
}

/* ============================================================
   Badges
   ============================================================ */
.badge{display:inline-block;font-family:"Inter",sans-serif;font-size:10px;font-weight:700;letter-spacing:0.12em;text-transform:uppercase;padding:3px 8px;border-radius:2px;color:#fff;line-height:1.4}
.badge-new{background:var(--new)}
.badge-fresh{background:var(--fresh)}
.badge-background{background:var(--background)}
.badge-risk{background:var(--risk)}

/* ============================================================
   Section rule (newspaper-style divider)
   ============================================================ */
.section-rule{display:flex;align-items:center;gap:14px;margin:46px 0 18px;padding-bottom:6px;border-bottom:2px solid var(--rule-strong)}
.section-rule .num{font-family:"Inter",sans-serif;font-size:13px;font-weight:800;color:var(--brand-blue);letter-spacing:0.1em}
.section-rule .name{font-family:"Noto Serif JP","Inter",serif;font-size:22px;font-weight:700;color:var(--ink)}
.section-rule .en{font-family:"Inter",sans-serif;font-size:11px;font-weight:600;letter-spacing:0.2em;text-transform:uppercase;color:var(--ink-mute);margin-left:auto}

/* ============================================================
   Story grids
   ============================================================ */
.story-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:0;border-top:1px solid var(--rule)}
.story{padding:18px 22px 22px;border-right:1px solid var(--rule);border-bottom:1px solid var(--rule)}
.story:nth-child(3n){border-right:none}
.story-meta{display:flex;align-items:center;gap:10px;margin-bottom:10px}
.story-date{font-family:"Inter",sans-serif;font-size:11.5px;color:var(--ink-mute);letter-spacing:0.05em}
.story-title{font-family:"Noto Serif JP","Inter",serif;font-size:18px;font-weight:700;color:var(--ink);margin:0 0 8px;line-height:1.45}
.story-body{font-size:13.5px;color:var(--ink-sub);margin:0 0 10px;line-height:1.75}
.story-source{font-size:11.5px;color:var(--ink-mute);font-family:"Inter","Noto Sans JP",sans-serif}

.story-wide{padding:22px 0;border-top:1px solid var(--rule);display:grid;grid-template-columns:1fr 2fr;gap:28px}
.story-wide:first-child{border-top:none}
.story-wide .label{font-family:"Inter",sans-serif;font-size:11px;font-weight:700;letter-spacing:0.2em;text-transform:uppercase;color:var(--brand-blue);margin-bottom:8px}
.story-wide .story-title{font-size:22px;line-height:1.4}

/* ============================================================
   Editorial / column
   ============================================================ */
.editorial{background:#fff;border:1px solid var(--rule);border-left:6px solid var(--brand-blue);padding:30px 34px;margin:48px 0 56px;position:relative}
.editorial::before{content:"きょうのひとこと";position:absolute;top:-12px;left:24px;background:#fff;padding:0 12px;font-family:"Noto Serif JP","Inter",serif;font-size:12px;font-weight:700;letter-spacing:0.15em;color:var(--brand-blue)}
.editorial h2{font-family:"Noto Serif JP","Inter",serif;font-size:24px;font-weight:700;margin:0 0 14px;color:var(--ink);line-height:1.4}
.editorial p{font-size:15px;line-height:1.95;color:var(--ink);margin:0 0 12px}
.editorial em{color:var(--brand-blue);font-weight:700;font-style:normal}
.editorial .byline{margin-top:14px;font-family:"Inter",sans-serif;font-size:12px;color:var(--ink-mute);letter-spacing:0.06em}

/* ============================================================
   Arena Snapshot widget (sidebar)
   ============================================================ */
.arena-snap{background:#fff;border:1px solid var(--rule);border-top:3px solid var(--brand-blue);
  border-radius:2px;padding:18px 18px 16px;margin-top:14px;position:relative}
.arena-snap::before{content:"ARENA";position:absolute;top:-9px;left:14px;background:#fff;
  padding:0 8px;font-family:"Inter",sans-serif;font-size:10px;font-weight:800;letter-spacing:0.22em;color:var(--brand-blue)}
.arena-head{display:flex;align-items:baseline;justify-content:space-between;gap:10px;margin-bottom:10px;padding-bottom:8px;border-bottom:1px solid var(--rule)}
.arena-head .cat{font-family:"Inter","Noto Sans JP",sans-serif;font-size:13px;font-weight:700;color:var(--ink);letter-spacing:0.02em}
.arena-head .cat .sub{font-family:"JetBrains Mono",monospace;font-size:10.5px;color:var(--ink-mute);margin-left:6px;letter-spacing:0.05em}
.arena-head .when{font-family:"JetBrains Mono",monospace;font-size:10.5px;color:var(--ink-mute);letter-spacing:0.05em}
.arena-head .when .dot{display:inline-block;width:6px;height:6px;border-radius:50%;background:var(--new-green);margin-right:5px;vertical-align:middle}
.arena-tabs{display:flex;gap:4px;flex-wrap:wrap;margin-bottom:10px}
.arena-tab{font-family:"Inter",sans-serif;font-size:10.5px;font-weight:600;letter-spacing:0.06em;text-transform:uppercase;
  padding:4px 9px;border-radius:3px;color:var(--ink-mute);background:#f2f5fa;cursor:pointer;transition:all 0.12s ease}
.arena-tab:hover{color:var(--brand-blue);background:#e8eef8;text-decoration:none}
.arena-tab.is-on{color:#fff;background:var(--brand-blue)}
.arena-tab.is-on:hover{color:#fff;background:var(--brand-blue-dark)}
.arena-guide-link{display:flex;align-items:center;justify-content:space-between;margin-bottom:10px;padding:7px 11px;background:var(--accent-bg);border-radius:4px;
  font-family:"Inter","Noto Sans JP",sans-serif;font-size:11.5px;color:var(--brand-blue);font-weight:600;border:1px dashed rgba(43,76,126,0.25)}
.arena-guide-link:hover{background:#e8eef8;text-decoration:none;border-color:var(--brand-blue)}
.arena-guide-link .ico{font-family:"JetBrains Mono",monospace;font-size:10px;letter-spacing:0.06em;color:var(--ink-mute);font-weight:700}
.arena-table{width:100%;border-collapse:collapse;font-family:"Inter","Noto Sans JP",sans-serif}
.arena-table th{font-family:"Inter",sans-serif;font-size:10px;font-weight:700;letter-spacing:0.12em;text-transform:uppercase;
  color:var(--ink-mute);text-align:left;padding:6px 4px 6px 0;border-bottom:1px solid var(--rule)}
.arena-table th.num,.arena-table td.num{text-align:right;font-variant-numeric:tabular-nums}
.arena-table td{padding:9px 4px 9px 0;border-bottom:1px solid var(--rule-soft);font-size:12.5px;color:var(--ink);vertical-align:middle}
.arena-table tr:last-child td{border-bottom:none}
.arena-rank{font-family:"JetBrains Mono",monospace;font-size:11.5px;font-weight:700;color:var(--ink-mute);width:24px}
.arena-rank.top{color:var(--brand-blue)}
.arena-model{font-weight:600;color:var(--ink);line-height:1.35}
.arena-model .vendor{display:block;font-family:"Inter",sans-serif;font-size:10.5px;font-weight:500;color:var(--ink-mute);letter-spacing:0.02em;margin-top:1px}
.arena-elo{font-family:"JetBrains Mono",monospace;font-size:12.5px;font-weight:700;color:var(--ink)}
.arena-delta{font-family:"JetBrains Mono",monospace;font-size:11px;font-weight:700;display:inline-block;min-width:34px;text-align:right;padding:2px 5px;border-radius:3px;letter-spacing:0.02em}
.arena-delta.up{color:var(--new-green);background:rgba(10,143,107,0.10)}
.arena-delta.down{color:var(--risk);background:rgba(185,83,28,0.12)}
.arena-delta.flat{color:var(--ink-mute);background:#f2f5fa}
.arena-foot{display:flex;justify-content:space-between;align-items:center;gap:10px;margin-top:10px;padding-top:8px;border-top:1px solid var(--rule);
  font-family:"Inter","Noto Sans JP",sans-serif;font-size:10.5px;color:var(--ink-mute)}
.arena-foot .pill-os{font-family:"JetBrains Mono",monospace;font-size:10px;font-weight:700;color:var(--new-green);background:rgba(10,143,107,0.10);padding:2px 7px;border-radius:3px;letter-spacing:0.06em}
.arena-foot a{color:var(--brand-blue);font-weight:600}

/* ============================================================
   Arena Guide page
   ============================================================ */
.hero-about{padding:48px 0 32px;background:linear-gradient(135deg,var(--accent-bg) 0%,#fff 100%);border-bottom:1px solid var(--rule)}
.hero-about .kicker{font-family:"Inter",sans-serif;font-size:11.5px;font-weight:700;letter-spacing:0.22em;text-transform:uppercase;color:var(--brand-blue);margin-bottom:14px;display:inline-flex;align-items:center;gap:10px}
.hero-about .kicker::before{content:"ARENA / Guide";background:var(--brand-blue);color:#fff;padding:3px 9px;border-radius:2px;font-size:10px;letter-spacing:0.18em}
.hero-about h1{font-family:"Noto Serif JP","Inter",serif;font-size:38px;font-weight:700;line-height:1.3;margin:0 0 14px;color:var(--ink);letter-spacing:-0.005em;max-width:760px}
.hero-about .deck{font-size:15px;color:var(--ink-sub);line-height:1.95;margin:0 0 18px;max-width:760px}
.hero-about .breadcrumb{font-family:"Inter",sans-serif;font-size:12px;color:var(--ink-mute);letter-spacing:0.05em}
.hero-about .breadcrumb a{color:var(--ink-mute)}
.hero-about .breadcrumb a:hover{color:var(--brand-blue)}

.toc{display:grid;grid-template-columns:repeat(5,1fr);gap:10px;padding:18px 0 0;border-bottom:1px solid var(--rule);margin-bottom:28px}
.toc a{display:flex;flex-direction:column;align-items:flex-start;gap:6px;padding:14px 14px 12px;border:1px solid var(--rule);border-radius:8px;color:var(--ink);transition:all 0.15s ease;background:#fff}
.toc a:hover{border-color:var(--brand-blue);transform:translateY(-2px);text-decoration:none;box-shadow:0 4px 14px rgba(43,76,126,0.08)}
.toc-num{font-family:"JetBrains Mono",monospace;font-size:10.5px;color:var(--brand-blue);font-weight:700;letter-spacing:0.1em}
.toc-name{font-family:"Inter","Noto Sans JP",sans-serif;font-size:14px;font-weight:700;color:var(--ink)}
.toc-jp{font-size:11.5px;color:var(--ink-mute)}

.intro{padding:8px 0 36px;border-bottom:1px solid var(--rule);margin-bottom:24px}
.intro h2{font-family:"Noto Serif JP","Inter",serif;font-size:22px;font-weight:700;color:var(--ink);margin:0 0 14px}
.intro p{font-size:14.5px;color:var(--ink-sub);line-height:1.9;margin:0 0 12px;max-width:820px}
.intro .factbox{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:24px}
.factbox .f{background:var(--accent-bg);border-radius:8px;padding:16px 18px}
.factbox .f-label{font-family:"Inter",sans-serif;font-size:10.5px;font-weight:700;letter-spacing:0.18em;text-transform:uppercase;color:var(--brand-blue);margin-bottom:6px}
.factbox .f-value{font-family:"Inter","Noto Sans JP",sans-serif;font-size:14.5px;font-weight:600;color:var(--ink);line-height:1.55}

.cat{padding:36px 0;border-bottom:1px solid var(--rule);scroll-margin-top:80px}
.cat:last-of-type{border-bottom:none}
.cat-head{display:grid;grid-template-columns:64px 1fr auto;gap:18px;align-items:start;margin-bottom:22px}
.cat-num{width:54px;height:54px;border-radius:12px;display:flex;align-items:center;justify-content:center;
  font-family:"Inter",sans-serif;font-size:22px;font-weight:800;color:#fff;letter-spacing:-0.01em}
.cat-num.c1{background:var(--brand-blue)}
.cat-num.c2{background:var(--accent-teal)}
.cat-num.c3{background:var(--accent-orange)}
.cat-num.c4{background:var(--accent-purple)}
.cat-num.c5{background:var(--accent-rose)}
.cat-title{font-family:"Noto Serif JP","Inter",serif;font-size:26px;font-weight:700;color:var(--ink);margin:0 0 4px;line-height:1.3}
.cat-title .en{font-family:"Inter",sans-serif;font-size:13px;color:var(--ink-mute);font-weight:600;margin-left:10px;letter-spacing:0.12em;text-transform:uppercase}
.cat-deck{font-size:14.5px;color:var(--ink-sub);margin:0;max-width:680px;line-height:1.9}
.cat-link{font-family:"JetBrains Mono",monospace;font-size:11px;font-weight:700;color:var(--brand-blue);letter-spacing:0.05em;padding-top:6px;white-space:nowrap}
.cat-link a{color:var(--brand-blue)}

.cat-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:24px;margin-top:8px}
.cat-block{background:#fff;border:1px solid var(--rule);border-radius:10px;padding:18px 20px}
.cat-block h3{font-family:"Inter","Noto Sans JP",sans-serif;font-size:13px;font-weight:700;color:var(--brand-blue);margin:0 0 12px;letter-spacing:0.05em;display:flex;align-items:center;gap:8px}
.cat-block h3::before{content:"";display:inline-block;width:14px;height:2px;background:var(--brand-blue)}
.cat-block p{font-size:13.5px;color:var(--ink-sub);line-height:1.85;margin:0 0 10px}
.cat-block ul{padding-left:18px;margin:0}
.cat-block li{font-size:13.5px;color:var(--ink-sub);line-height:1.85;margin-bottom:4px}
.cat-block .ex{display:flex;flex-direction:column;gap:8px;margin-top:6px}
.cat-block .ex-item{font-size:13px;color:var(--ink);background:var(--accent-bg);border-radius:6px;padding:8px 12px;line-height:1.55}
.cat-block .ex-item b{color:var(--brand-blue);font-weight:600;font-family:"JetBrains Mono",monospace;font-size:11px;letter-spacing:0.05em;display:block;margin-bottom:2px;text-transform:uppercase}
.cat-models{display:flex;flex-wrap:wrap;gap:6px;margin-top:6px}
.cat-model{font-family:"Inter",sans-serif;font-size:11.5px;font-weight:600;color:var(--ink);background:#fff;border:1px solid var(--rule);padding:4px 10px;border-radius:999px}
.cat-model .v{color:var(--ink-mute);font-weight:500;margin-left:5px}

.cat-aside{display:flex;flex-direction:column;gap:14px}
.aside-block{background:var(--accent-bg);border-radius:10px;padding:18px 20px}
.aside-block h4{font-family:"Inter",sans-serif;font-size:11px;font-weight:700;letter-spacing:0.18em;text-transform:uppercase;color:var(--brand-blue);margin:0 0 10px}
.aside-block p{font-size:13px;color:var(--ink-sub);line-height:1.85;margin:0}
.who{display:flex;flex-direction:column;gap:8px;margin-top:4px}
.who-row{display:flex;align-items:center;gap:10px;font-size:12.5px;color:var(--ink)}
.who-icon{width:22px;height:22px;border-radius:50%;background:#fff;display:inline-flex;align-items:center;justify-content:center;color:var(--brand-blue);font-family:"Inter",sans-serif;font-size:10px;font-weight:700;border:1px solid var(--rule)}
.stars{font-family:"Inter",monospace;color:var(--brand-blue);font-size:13px;letter-spacing:0.05em;margin-left:auto;font-weight:700}
.stars .off{color:var(--rule)}

.glossary{background:var(--accent-bg);border-radius:10px;padding:26px 28px;margin:36px 0 48px}
.glossary h2{font-family:"Noto Serif JP","Inter",serif;font-size:18px;font-weight:700;margin:0 0 14px;color:var(--ink)}
.glossary dl{margin:0;display:grid;grid-template-columns:140px 1fr;gap:8px 18px}
.glossary dt{font-family:"Inter",sans-serif;font-size:12.5px;font-weight:700;color:var(--brand-blue);letter-spacing:0.04em}
.glossary dd{font-size:13px;color:var(--ink-sub);margin:0;line-height:1.8}

/* ============================================================
   Archive page
   ============================================================ */
.archive-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:18px;padding:40px 0 60px}
.archive-card{display:block;padding:22px 22px 20px;background:#fff;border:1px solid var(--rule);border-radius:10px;color:var(--ink);transition:border-color 0.15s ease,transform 0.15s ease}
.archive-card:hover{text-decoration:none;border-color:var(--brand-blue);transform:translateY(-2px)}
.archive-card-date{font-family:"Inter",sans-serif;font-size:12px;font-weight:600;letter-spacing:0.1em;color:var(--brand-blue);margin-bottom:10px}
.archive-card-title{font-family:"Noto Serif JP","Noto Sans JP",sans-serif;font-size:15.5px;font-weight:600;line-height:1.6;color:var(--ink);margin-bottom:14px}
.archive-card-tags{display:flex;flex-wrap:wrap;gap:6px}
.archive-card-tag{font-family:"Noto Sans JP",sans-serif;font-size:11px;font-weight:500;padding:3px 9px;background:var(--accent-bg);color:var(--brand-blue);border-radius:3px}

/* ============================================================
   About page
   ============================================================ */
.about-hero{padding:50px 0 30px;border-bottom:1px solid var(--rule);background:linear-gradient(135deg,var(--accent-bg) 0%,#fff 100%)}
.about-hero h1{font-family:"Noto Serif JP","Inter",serif;font-size:36px;font-weight:700;margin:0 0 14px;color:var(--ink);max-width:760px;letter-spacing:-0.005em}
.about-hero .deck{font-size:15.5px;color:var(--ink-sub);line-height:1.9;max-width:760px;margin:0}
.about-eyebrow{font-family:"Inter",sans-serif;font-size:11.5px;font-weight:700;letter-spacing:0.22em;text-transform:uppercase;color:var(--brand-blue);margin-bottom:14px;display:inline-block}

.about-card{background:#fff;border:1px solid var(--rule);border-radius:10px;padding:30px 32px;margin:0 0 18px}
.about-card h2{font-family:"Noto Serif JP","Inter",serif;font-size:20px;font-weight:700;margin:0 0 14px;color:var(--ink)}
.about-card p{font-size:14.5px;color:var(--ink-sub);line-height:1.9;margin:0 0 10px}
.about-card ul{font-size:14.5px;color:var(--ink-sub);line-height:1.85;padding-left:22px;margin:6px 0 0}

/* ============================================================
   404
   ============================================================ */
.notfound{padding:80px 0 100px;text-align:center}
.notfound .code{font-family:"JetBrains Mono",monospace;font-size:96px;font-weight:700;color:var(--brand-blue);letter-spacing:-0.02em;margin:0;line-height:1}
.notfound h1{font-family:"Noto Serif JP","Inter",serif;font-size:26px;font-weight:700;color:var(--ink);margin:14px 0 12px}
.notfound p{font-size:14.5px;color:var(--ink-sub);max-width:520px;margin:0 auto 22px;line-height:1.85}
.notfound .actions{display:flex;justify-content:center;gap:14px}
.notfound .btn{display:inline-flex;align-items:center;padding:10px 20px;font-family:"Inter","Noto Sans JP",sans-serif;font-size:13px;font-weight:600;letter-spacing:0.06em;text-transform:uppercase;color:#fff;background:var(--brand-blue);border-radius:4px;transition:background 0.15s ease}
.notfound .btn:hover{background:var(--brand-blue-dark);text-decoration:none}
.notfound .btn.outline{background:transparent;color:var(--brand-blue);border:1px solid var(--brand-blue)}
.notfound .btn.outline:hover{background:var(--accent-bg)}

/* ============================================================
   Footer
   ============================================================ */
.site-footer{background:var(--brand-blue);color:#fff;padding:42px 0 24px;margin-top:20px}
.site-footer-top{display:grid;grid-template-columns:2fr 1fr 1fr;gap:36px;padding-bottom:28px;border-bottom:1px solid rgba(255,255,255,0.2)}
.footer-brand{display:flex;flex-direction:column;gap:10px}
.footer-brand .title{font-family:"Noto Serif JP","Inter",serif;font-size:22px;font-weight:700}
.footer-desc{font-size:13px;color:rgba(255,255,255,0.78);line-height:1.85;max-width:520px}
.footer-nav{display:flex;flex-direction:column;gap:8px}
.footer-nav-title{font-family:"Inter",sans-serif;font-size:11px;font-weight:700;letter-spacing:0.2em;text-transform:uppercase;color:rgba(255,255,255,0.6);margin-bottom:6px}
.footer-nav a{color:rgba(255,255,255,0.9);font-size:13px}
.site-footer-bottom{display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;padding-top:18px;font-family:"Inter",sans-serif;font-size:12px;color:rgba(255,255,255,0.6)}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width:880px){
  .topics-grid{grid-template-columns:1fr}
  .topics-head{flex-direction:column;align-items:flex-start;gap:6px}
  .story-grid{grid-template-columns:1fr}
  .story{border-right:none}
  .story-wide{grid-template-columns:1fr;gap:8px}
  .site-footer-top{grid-template-columns:1fr}
  .topics-head .title{font-size:22px}
  .toc{grid-template-columns:repeat(2,1fr)}
  .cat-head{grid-template-columns:48px 1fr}
  .cat-link{grid-column:1/-1;padding-left:66px}
  .cat-num{width:44px;height:44px;font-size:18px}
  .cat-title{font-size:22px}
  .cat-grid{grid-template-columns:1fr}
  .intro .factbox{grid-template-columns:1fr}
  .glossary dl{grid-template-columns:1fr}
  .about-hero h1{font-size:26px}
  .notfound .code{font-size:64px}
}