:root{--navy:#003366;--blue:#007bff;--ink:#2b333b;--muted:#5f6872;--line:#dbe2ea;--bg:#f6f8fb;--pale:#eef4fb}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:84px}
body{font-family:'Noto Sans JP',sans-serif;color:var(--ink);background:#fff;line-height:1.9;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
.wrap{width:min(1080px,100% - 32px);margin-inline:auto}

/* header */
.hd{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.96);backdrop-filter:blur(6px);border-bottom:1px solid #edf1f4}
.hd-in{height:64px;display:flex;align-items:center;justify-content:space-between;gap:12px}
.logo{color:var(--navy);font-weight:800;font-size:1.35rem;letter-spacing:.08em}
.hd ul{list-style:none;display:flex;align-items:center;gap:22px;font-size:.88rem;font-weight:700}
.hd ul a:hover{color:var(--blue)}
.hd .cta{background:var(--navy);color:#fff;padding:7px 16px;border-radius:99px}
.hd .cta:hover{background:var(--blue);color:#fff}

/* common */
.bc{font-size:.8rem;color:var(--muted);padding:22px 0 10px}
.bc a{text-decoration:underline;text-underline-offset:2px}
.tag{display:inline-block;background:var(--pale);color:var(--navy);font-size:.75rem;font-weight:700;padding:2px 12px;border-radius:99px}
.sm-ttl{font-weight:800;color:var(--navy);font-size:.9rem;margin-bottom:8px}

/* article */
.art{max-width:800px}
.art-hd{padding:6px 0 22px}
.art-hd h1{font-size:clamp(1.5rem,3.6vw,2.1rem);line-height:1.45;color:var(--navy);margin:12px 0 12px}
.meta{font-size:.82rem;color:var(--muted)}
.meta a{text-decoration:underline;text-underline-offset:2px}
.summary{background:var(--pale);border-left:4px solid var(--navy);border-radius:8px;padding:18px 22px;margin:8px 0 22px}
.summary ul{padding-left:1.2em}
.summary li{margin:4px 0;font-weight:500}
.toc{border:1px solid var(--line);border-radius:8px;padding:16px 22px;margin-bottom:34px}
.toc ol{padding-left:1.4em;font-size:.92rem}
.toc a{color:var(--navy);text-decoration:underline;text-underline-offset:2px}
.body section{margin-bottom:38px}
.body h2,.faq h2,.related h2{font-size:clamp(1.25rem,2.6vw,1.5rem);line-height:1.5;color:var(--navy);border-bottom:2px solid var(--navy);padding-bottom:8px;margin-bottom:18px}
.body h3{font-size:1.1rem;color:var(--navy);margin:26px 0 10px;padding-left:12px;border-left:4px solid var(--blue)}
.body p{margin:0 0 16px}
.body ul,.body ol{margin:0 0 18px;padding-left:1.4em}
.body li{margin:5px 0}
.body strong{background:linear-gradient(transparent 62%,#dbeafe 62%)}
.body table{width:100%;border-collapse:collapse;margin:6px 0 20px;font-size:.92rem;display:block;overflow-x:auto}
.body th,.body td{border:1px solid var(--line);padding:10px 12px;text-align:left;vertical-align:top;min-width:110px}
.body th{background:var(--pale);color:var(--navy)}
.point,.note{border-radius:8px;padding:14px 18px;margin:0 0 18px}
.point{background:#f0f7ff;border:1px solid #cfe3fb}
.note{background:#fafafa;border:1px solid var(--line);font-size:.92rem;color:var(--muted)}
.point p:last-child,.note p:last-child{margin-bottom:0}

.faq{margin:10px 0 30px}
.faq details{border:1px solid var(--line);border-radius:8px;margin-bottom:10px;background:#fff}
.faq summary{cursor:pointer;font-weight:700;padding:14px 18px;color:var(--navy)}
.faq details p{padding:0 18px 16px}

.cta-box{background:var(--navy);color:#fff;border-radius:12px;padding:26px 24px;margin:34px 0;text-align:center}
.cta-ttl{font-weight:800;font-size:1.1rem;margin-bottom:8px}
.cta-box p{opacity:.95}
.cta-btns{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;margin-top:16px}
.btn-main,.btn-sub{display:inline-block;padding:12px 24px;border-radius:99px;font-weight:700}
.btn-main{background:#fff;color:var(--navy)}
.btn-main:hover{background:var(--blue);color:#fff}
.btn-sub{border:1px solid rgba(255,255,255,.7);color:#fff}
.btn-sub:hover{background:rgba(255,255,255,.12)}

.author{border:1px solid var(--line);border-radius:10px;padding:18px 22px;font-size:.9rem;margin-bottom:40px}
.author .name{font-weight:800;font-size:1.05rem;margin-bottom:6px}
.author small{font-weight:500;color:var(--muted);margin-left:6px}

.related{margin-bottom:60px}
.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:12px}
.cards-2{grid-template-columns:repeat(auto-fill,minmax(300px,1fr))}
.card{position:relative;display:flex;flex-direction:column;gap:8px;border-radius:12px;padding:20px 22px 40px;background:#003366;color:#fff;box-shadow:0 6px 18px rgba(0,51,102,.16);transition:transform .2s,box-shadow .2s,background .2s}
.card:hover{transform:translateY(-3px);box-shadow:0 10px 24px rgba(0,51,102,.28);background:#0b4c8f}
.card b{color:#fff;line-height:1.6;font-size:1rem}
.card span:not(.tag){font-size:.84rem;color:rgba(255,255,255,.82);line-height:1.75}
.card .tag{align-self:flex-start;background:rgba(255,255,255,.16);color:#fff;border:1px solid rgba(255,255,255,.35)}
.card::after{content:"記事を読む →";position:absolute;right:20px;bottom:14px;font-size:.78rem;font-weight:700;opacity:.85}

/* index */
.art-index{max-width:1080px}
.idx-hd{padding:8px 0 26px}
.idx-hd h1{font-size:clamp(1.6rem,3.6vw,2.2rem);color:var(--navy);margin:10px 0}
.idx-hd p{color:var(--muted);max-width:760px}
.chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.chips a{border:1px solid var(--line);border-radius:99px;padding:5px 14px;font-size:.85rem;font-weight:700;color:var(--navy)}
.chips a:hover{background:var(--navy);color:#fff}
.cat{margin:30px 0 40px}
.cat h2{font-size:1.35rem;color:var(--navy);border-bottom:2px solid var(--navy);padding-bottom:6px}
.cat .lead{color:var(--muted);font-size:.9rem;margin:8px 0 14px}

/* footer */
.ft{background:#101820;color:#8f99a4;font-size:.84rem;padding:28px 0;text-align:center}
.ft nav{display:flex;flex-wrap:wrap;justify-content:center;gap:8px 18px;margin-bottom:10px}
.ft a:hover{color:#fff}

@media(max-width:700px){
  .hd ul{gap:12px;font-size:.78rem}
  .hd ul li:nth-child(3){display:none}
  .logo{font-size:1.1rem}
  .hd .cta{padding:6px 12px}
  .summary,.toc{padding:14px 16px}
  .cta-box{padding:22px 16px}
}