@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@300;400;500;700&family=Shippori+Mincho:wght@500;600;700&display=swap');
:root{--paper:#fbfaf6;--soft:#f1efe7;--ink:#1b1f1a;--muted:#5a6157;--green:#2f6a4a;--deep:#1f4a34;--tint:#e5eee7;--amber:#c0561a;--amber-deep:#a34612;--line:rgba(27,31,26,.13);--serif:'Shippori Mincho','Hiragino Mincho ProN',serif;--sans:'Noto Sans JP','Hiragino Kaku Gothic ProN',sans-serif}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:104px}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--sans);font-weight:400;line-height:1.95;letter-spacing:.02em;-webkit-text-size-adjust:100%}
a{color:inherit;text-decoration:none}
img{max-width:100%;height:auto;display:block}
:focus-visible{outline:3px solid var(--amber);outline-offset:3px}
.shell,.article-shell{max-width:1120px;margin:auto;padding:0 40px}
.article-shell{max-width:840px}
.article-shell.wide{max-width:1120px}
.progress{position:fixed;top:0;left:0;right:0;height:3px;z-index:30;background:transparent}
.progress i{display:block;height:100%;width:0;background:var(--amber)}
.site-header{height:80px;padding:0 5vw;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);background:rgba(251,250,246,.96);backdrop-filter:blur(6px);position:sticky;top:0;z-index:20}
.brand{display:flex;align-items:center;gap:14px}
.brand img{width:108px}
.brand span,.category{font-size:11px;letter-spacing:.22em;color:var(--green);font-weight:700}
.site-header nav{display:flex;align-items:center;gap:28px;font-size:13px;font-weight:500}
.site-header nav a:not(.nav-cta):hover{color:var(--green)}
.nav-cta,.button{background:var(--amber);color:#fff;padding:13px 24px;font-weight:700;font-size:14px;display:inline-flex;align-items:center;justify-content:center;gap:14px;border-radius:2px;transition:background .2s}
.nav-cta{padding:11px 20px;font-size:13px}
.nav-cta:hover,.button:hover{background:var(--amber-deep)}
.button.ghost{background:transparent;color:#fff;border:1px solid rgba(255,255,255,.7)}
.button.ghost:hover{background:rgba(255,255,255,.12)}

/* hero (index + article share one two-column layout) */
.index-hero,.article-hero{background:linear-gradient(135deg,var(--paper),var(--tint));border-bottom:1px solid var(--line)}
.hero-grid{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);gap:56px;align-items:center}
.index-hero{padding:76px 0 80px}
.article-hero{padding:48px 0 56px}
.hero-img{width:100%;aspect-ratio:1200/630;object-fit:cover;border-radius:4px;box-shadow:0 18px 40px -22px rgba(31,74,52,.55)}
.index-hero h1,.article-hero h1{font-family:var(--serif);font-weight:600;line-height:1.5;letter-spacing:.04em;margin:14px 0 20px;text-wrap:balance}
.index-hero h1{font-size:clamp(32px,4.6vw,52px)}
.article-hero h1{font-size:clamp(26px,3.3vw,38px)}
.lead{color:var(--muted);margin:0}
.meta{display:flex;gap:18px;flex-wrap:wrap;margin:22px 0 0;font-size:12px;color:var(--muted)}
.breadcrumbs{font-size:12px;color:var(--muted);display:flex;gap:10px;margin-bottom:26px;flex-wrap:wrap}
.breadcrumbs a:hover{color:var(--green)}
.quick{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:30px}
.quick a{background:#fff;border:1px solid var(--line);padding:14px 16px;border-radius:3px;display:flex;flex-direction:column;line-height:1.5;transition:border-color .2s,transform .2s}
.quick a:hover{border-color:var(--green);transform:translateY(-2px)}
.quick strong{font-size:14px}
.quick span{font-size:12px;color:var(--muted)}

/* start here */
.start{padding:64px 0 24px}
.start h2,.section-heading h2{font:600 30px/1.5 var(--serif);margin:6px 0 0}
.start-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:28px}
.start-card,.rel-card{display:flex;flex-direction:column;gap:8px;line-height:1.6}
.start-card img,.rel-card img{aspect-ratio:1200/630;object-fit:cover;border-radius:3px;margin-bottom:6px;transition:transform .4s}
.start-card,.rel-card{overflow:hidden}
.start-card:hover img,.rel-card:hover img{transform:scale(1.03)}
.start-card strong,.rel-card strong{font:600 17px/1.6 var(--serif)}

/* index sections + cards */
.index-section{padding:64px 0 8px}
.index-section:last-of-type{padding-bottom:110px}
.section-heading{margin-bottom:28px}
.section-heading p:last-child{color:var(--muted);margin:6px 0 0;font-size:14px}
.card-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.card-grid.two{grid-template-columns:repeat(2,1fr)}
.card{background:#fff;border:1px solid var(--line);display:flex;flex-direction:column;border-radius:3px;overflow:hidden;transition:box-shadow .25s,transform .25s}
.card:hover{box-shadow:0 16px 30px -20px rgba(27,31,26,.5);transform:translateY(-3px)}
.card-img img{aspect-ratio:1200/630;object-fit:cover;width:100%}
.card-body{padding:22px 24px 26px;display:flex;flex-direction:column;flex:1}
.card h3{font:600 18px/1.65 var(--serif);margin:8px 0 10px}
.card-desc{font-size:13px;color:var(--muted);margin:0 0 18px;line-height:1.85}
.text-link{margin-top:auto;color:var(--green);font-size:13px;font-weight:700}

/* article layout */
.article-layout{display:grid;grid-template-columns:minmax(0,1fr) 250px;gap:56px;align-items:start;padding-top:56px;padding-bottom:96px}
.article-body{min-width:0;max-width:740px}
.summary{background:var(--tint);border-radius:4px;padding:22px 26px;margin-bottom:38px}
.summary-title{margin:0 0 8px;font-weight:700;color:var(--deep);font-size:14px;letter-spacing:.08em}
.summary ol{margin:0;padding-left:1.4em;font-size:15px;line-height:1.9}
.article-body .intro{font-size:17px;line-height:2.05;margin:0 0 48px}
.article-body section{margin:0 0 46px}
.article-body h2{font:600 24px/1.6 var(--serif);margin:0 0 14px;padding-bottom:10px;border-bottom:1px solid var(--line)}
.article-body p{margin:0;color:#2f342d}
.article-body section>p+.table-wrap{margin-top:22px}
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:3px;background:#fff}
table{border-collapse:collapse;width:100%;min-width:520px;font-size:14px;line-height:1.7}
caption{text-align:left;padding:12px 14px;font-weight:700;font-size:13px;color:var(--deep)}
th,td{border-top:1px solid var(--line);padding:11px 14px;text-align:left;vertical-align:top}
thead th{background:var(--tint);font-weight:700}
tbody th{font-weight:500;background:var(--soft);white-space:nowrap}
.table-note{font-size:12px!important;color:var(--muted)!important;margin-top:10px!important}
.mid-cta{margin:0 0 46px;padding:22px 26px;background:#fff;border:1px solid var(--amber);border-radius:4px;display:flex;align-items:center;justify-content:space-between;gap:18px;flex-wrap:wrap}
.mid-cta p{font-weight:500;margin:0;flex:1 1 220px}
.source{padding:18px 22px;background:var(--soft);font-size:13px;margin:0 0 46px;border-radius:3px}
.source strong,.source a{display:block}
.source a{color:var(--green);margin-top:6px;text-decoration:underline}
.faq details{border-bottom:1px solid var(--line)}
.faq summary{cursor:pointer;padding:16px 30px 16px 0;font-weight:700;position:relative;list-style:none;line-height:1.7}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:'+';position:absolute;right:4px;top:12px;font-size:22px;color:var(--green);font-weight:300}
.faq details[open] summary::after{content:'−'}
.faq details p{padding:0 0 18px;font-size:15px}
.article-cta{margin:60px 0 32px;padding:42px;background:var(--deep);color:#fff;border-radius:4px}
.article-body .article-cta p{color:rgba(255,255,255,.78)}
.article-cta h2{color:#fff;border:0;padding:0;font-size:26px;margin:6px 0 24px}
.cta-row{display:flex;gap:12px;flex-wrap:wrap}
.publisher{font-size:13px;color:var(--muted);border-top:1px solid var(--line);padding-top:22px}
.publisher strong{color:var(--ink)}
.publisher p{margin:6px 0 0;color:var(--muted)}
.publisher a{color:var(--green);text-decoration:underline;margin-left:10px}

/* toc */
.toc{position:sticky;top:104px;font-size:13px;line-height:1.7;border-left:2px solid var(--line);padding-left:20px}
.toc summary{font-weight:700;font-size:12px;letter-spacing:.2em;color:var(--green);cursor:pointer;list-style:none;margin-bottom:8px}
.toc summary::-webkit-details-marker{display:none}
.toc ol{margin:0;padding:0;list-style:none;display:flex;flex-direction:column;gap:8px}
.toc a:hover{color:var(--green);text-decoration:underline}
.side-cta{margin-top:22px;width:100%}

/* related */
.related{background:var(--soft);padding:60px 0 80px;border-top:1px solid var(--line)}
.related h2{font:600 24px/1.5 var(--serif);margin:0 0 24px}
.rel-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}

footer{background:#17281e;color:#fff;padding:52px 0}
.footer-inner{display:grid;grid-template-columns:1fr auto;gap:22px;align-items:center}
.footer-brand img{background:#fff;border-radius:8px;padding:6px 10px;box-sizing:content-box;margin-left:-10px}
.footer-brand span{color:rgba(255,255,255,.7)}
footer a{margin-left:22px;font-size:13px}
footer p{grid-column:1/-1;margin:0;color:rgba(255,255,255,.55);font-size:12px}

@media(max-width:960px){
  .article-layout{grid-template-columns:1fr;gap:0}
  .toc{position:static;order:-1;border-left:0;padding:0;margin-bottom:28px}
  .toc details{background:#fff;border:1px solid var(--line);border-radius:3px;padding:12px 16px}
  .toc .side-cta{display:none}
  .article-layout .article-body{order:2}
  .card-grid,.start-grid,.rel-grid{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:780px){
  .shell,.article-shell{padding:0 20px}
  .site-header{height:64px;padding:0 16px}
  .brand img{width:88px}
  .brand span{font-size:9px}
  .site-header nav>a:not(.nav-cta){display:none}
  .nav-cta{padding:10px 14px;font-size:12px}
  .hero-grid{grid-template-columns:1fr;gap:26px}
  .hero-img{order:-1}
  .index-hero{padding:34px 0 48px}
  .article-hero{padding:24px 0 40px}
  .quick{grid-template-columns:1fr 1fr}
  .card-grid,.card-grid.two,.start-grid,.rel-grid{grid-template-columns:1fr}
  .start{padding-top:44px}
  .article-layout{padding-top:32px;padding-bottom:64px}
  .article-body .intro{font-size:16px}
  .article-body h2{font-size:21px}
  .article-cta{padding:30px 22px}
  .article-cta h2{font-size:22px}
  .cta-row .button{width:100%}
  .mid-cta .button{width:100%}
  .footer-inner{display:block}
  .footer-inner>div{margin:24px 0}
  .footer-inner>div a{display:block;margin:8px 0}
}
@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}

.about-col{padding:56px 0;background:#fff;border-top:1px solid var(--line)}
.about-col .shell{max-width:760px}
.about-col h2{font-size:22px;margin:0 0 14px}
.about-col p{color:var(--muted);line-height:1.9;font-size:14.5px;margin:0 0 10px}
.about-links{display:flex;flex-wrap:wrap;gap:8px 20px;margin-top:14px!important}
.about-links a{color:var(--green);text-decoration:underline}

.table-note{font-size:12.5px;color:var(--muted);margin:6px 0 0}
.calc{border:1px solid var(--line);border-radius:6px;padding:16px;background:#fff;margin:14px 0}
.calc-row{display:flex;gap:16px;flex-wrap:wrap}
.calc label{font-size:13px;color:var(--muted);display:flex;flex-direction:column;gap:4px}
.calc input,.calc select{font-size:16px;padding:8px 10px;border:1px solid var(--line);border-radius:4px;min-width:120px;background:#fff}
.calc-out{display:block;margin-top:12px;line-height:1.9;font-size:14.5px}
.cases{margin:40px 0}
.case-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
.case-card{display:block;border:1px solid var(--line);border-radius:6px;overflow:hidden;background:#fff;text-decoration:none;color:var(--ink)}
.case-card img{width:100%;height:auto;aspect-ratio:1200/630;object-fit:cover;display:block}
.case-card strong{display:block;padding:10px 12px;font-size:13.5px;line-height:1.6}
.cases-note{font-size:12.5px;color:var(--muted)}
.cases-note a{color:var(--green);text-decoration:underline}
@media(max-width:640px){.case-grid{grid-template-columns:1fr}}
.article-body .article-cta .cta-note{font-size:13px;margin:18px 0 0;color:rgba(255,255,255,.75)}
.price-mark{background:linear-gradient(transparent 62%,#fde68a 62%);font-weight:600;padding:0 2px}