:root{
  --bg:#f6f8fb;
  --card:#ffffff;
  --text:#172033;
  --muted:#5d6878;
  --line:#dfe5ec;
  --brand:#2457d6;
  --brand2:#0f7b74;
  --accent:#fff5d9;
  --max:1080px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Noto Sans JP","Hiragino Kaku Gothic ProN","Yu Gothic",sans-serif;
  color:var(--text);
  background:var(--bg);
  line-height:1.75;
}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
header{
  background:#fff;
  border-bottom:1px solid var(--line);
  position:sticky;top:0;z-index:20;
}
.wrap{max-width:var(--max);margin:0 auto;padding:0 24px}
.nav{display:flex;align-items:center;justify-content:space-between;min-height:72px;gap:24px}
.logo{font-size:1.2rem;font-weight:800;color:var(--text);letter-spacing:.01em}
.logo small{display:block;font-size:.72rem;font-weight:600;color:var(--muted);margin-top:-4px}
nav ul{display:flex;list-style:none;gap:20px;margin:0;padding:0;font-size:.92rem}
.hero{padding:72px 0 44px;background:linear-gradient(180deg,#fff 0%,#f6f8fb 100%)}
.hero-grid{display:grid;grid-template-columns:1.4fr .9fr;gap:44px;align-items:center}
.kicker{font-size:.86rem;font-weight:700;color:var(--brand2);letter-spacing:.08em}
h1{font-size:clamp(2rem,5vw,3.6rem);line-height:1.16;margin:.4rem 0 1rem;letter-spacing:-.03em}
h2{font-size:1.65rem;line-height:1.35;margin:0 0 16px}
h3{font-size:1.15rem;margin:0 0 8px}
.lead{font-size:1.08rem;color:var(--muted);max-width:720px}
.hero-card,.card,.article-box{
  background:var(--card);
  border:1px solid var(--line);
  border-radius:18px;
  box-shadow:0 8px 28px rgba(30,45,70,.05);
}
.hero-card{padding:28px}
.hero-card ul{margin:0;padding-left:1.2em}
.section{padding:52px 0}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.card{padding:24px}
.card p{color:var(--muted);margin-bottom:0}
.btn{display:inline-block;background:var(--brand);color:#fff!important;padding:12px 18px;border-radius:10px;font-weight:700}
.btn:hover{text-decoration:none;opacity:.92}
.tag{display:inline-block;font-size:.78rem;padding:4px 9px;border-radius:999px;background:#eef3ff;color:var(--brand);font-weight:700;margin-bottom:10px}
.notice{background:var(--accent);border:1px solid #f0dfaf;border-radius:14px;padding:16px 18px;color:#5d4b1e}
.article-list{display:grid;gap:16px}
.article-link{display:block;background:#fff;border:1px solid var(--line);border-radius:16px;padding:22px;color:var(--text)}
.article-link:hover{text-decoration:none;border-color:#b9c6d8}
.article-link p{color:var(--muted);margin:6px 0 0}
main.page{padding:48px 0 72px}
.content{max-width:820px;margin:0 auto}
.content h1{font-size:2.25rem}
.content h2{margin-top:38px;border-bottom:1px solid var(--line);padding-bottom:9px}
.content h3{margin-top:28px}
.content p,.content li{color:#2e394b}
.content table{width:100%;border-collapse:collapse;margin:18px 0}
.content th,.content td{border:1px solid var(--line);padding:11px;text-align:left;vertical-align:top}
.content th{background:#f1f4f8}
.breadcrumbs{font-size:.86rem;color:var(--muted);margin-bottom:22px}
.meta{font-size:.88rem;color:var(--muted);margin:-8px 0 28px}
.article-box{padding:22px;margin:26px 0}
footer{background:#101827;color:#d8dee8;padding:34px 0;margin-top:40px}
footer a{color:#fff}
.footer-grid{display:flex;justify-content:space-between;gap:28px;align-items:flex-start}
.footer-links{display:flex;flex-wrap:wrap;gap:14px;font-size:.86rem}
.copy{font-size:.8rem;color:#98a5b8;margin-top:18px}
@media(max-width:760px){
  .nav{align-items:flex-start;padding:16px 0;flex-direction:column}
  nav ul{gap:12px;flex-wrap:wrap}
  .hero{padding-top:44px}
  .hero-grid,.grid3{grid-template-columns:1fr}
  .footer-grid{flex-direction:column}
  .wrap{padding:0 18px}
}