:root{--ink:#1c2430;--mute:#5b6675;--line:#dfe3e8;--bg:#ffffff;--soft:#f5f7fa;--navy:#1f3a5f;--navy-d:#172c49;--ok:#1d7a4f;--max:980px}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font-family:'Noto Sans JP','Hiragino Sans','Yu Gothic UI','Meiryo',sans-serif;color:var(--ink);background:var(--bg);line-height:1.75;font-size:16px}
a{color:var(--navy)}
img{max-width:100%}
.wrap{max-width:var(--max);margin:0 auto;padding:0 16px}
header.site{border-bottom:1px solid var(--line);background:#fff;position:sticky;top:0;z-index:20}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;height:56px}
.logo{font-weight:700;font-size:18px;color:var(--ink);text-decoration:none;letter-spacing:.02em;white-space:nowrap}
.logo small{font-weight:500;color:var(--mute);font-size:12px;margin-left:8px}
nav.g{display:flex;gap:4px;flex-wrap:nowrap}
nav.g a{color:var(--mute);text-decoration:none;font-size:14px;padding:12px 8px;white-space:nowrap;line-height:1.3}
nav.g a:hover{color:var(--navy)}
@media(max-width:480px){.logo small{display:none}}
.btn{display:inline-block;background:var(--navy);color:#fff;text-decoration:none;padding:14px 22px;border-radius:8px;font-weight:600;border:0;cursor:pointer;font-size:16px;line-height:1.3;text-align:center;font-family:inherit}
.btn:hover{background:var(--navy-d)}
.btn.o{background:#fff;color:var(--navy);border:1.5px solid var(--navy)}
.btn.o:hover{background:var(--soft)}
.btn.sm{padding:9px 14px;font-size:14px;border-radius:6px}
.btn.wide{display:block;width:100%}
.btn[disabled]{opacity:.5;cursor:default}
.hero{padding:44px 0 32px}
.hero h1{font-size:30px;line-height:1.35;margin:0 0 14px;letter-spacing:.01em}
.hero p.lead{font-size:17px;color:var(--mute);margin:0 0 24px}
.ctas{display:grid;grid-template-columns:1fr;gap:10px;max-width:560px}
.ctas .btn{padding:16px 18px}
.ctas .btn span{display:block;font-size:12px;font-weight:400;opacity:.85;margin-top:2px}
.note{font-size:13px;color:var(--mute)}
section.blk{padding:36px 0;border-top:1px solid var(--line)}
section.blk h2{font-size:22px;margin:0 0 18px;line-height:1.4}
.cards{display:grid;grid-template-columns:1fr;gap:14px}
.card{border:1px solid var(--line);border-radius:10px;padding:18px;background:#fff}
.card h3{margin:0 0 6px;font-size:17px}
.card p{margin:0;color:var(--mute);font-size:15px}
.steps{display:grid;gap:12px}
.step{display:flex;gap:14px;align-items:flex-start}
.step .n{flex:0 0 34px;height:34px;border-radius:50%;background:var(--navy);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:700}
.step h3{margin:2px 0 4px;font-size:16px}
.step p{margin:0;color:var(--mute);font-size:15px}
.links{display:grid;grid-template-columns:1fr 1fr;gap:8px 16px}
.links a{font-size:15px;text-decoration:none;color:var(--navy);padding:10px 0;border-bottom:1px solid var(--line);overflow-wrap:anywhere;display:flex;align-items:center;min-height:44px}
.cat .links{grid-template-columns:1fr}
.more a{display:inline-block;padding:10px 0;margin-right:18px}
details{border:1px solid var(--line);border-radius:8px;padding:12px 16px;margin-bottom:8px;background:#fff}
summary{cursor:pointer;font-weight:600}
details p{margin:8px 0 0;color:var(--mute);font-size:15px}
footer.site{border-top:1px solid var(--line);padding:28px 0 40px;color:var(--mute);font-size:13px;margin-top:40px}
footer.site .fl a{color:var(--mute);text-decoration:none;margin-right:12px;display:inline-block;padding:10px 2px}
.crumb a{display:inline-block;padding:8px 0}
footer.site p{margin:8px 0 0}
.doc h1{font-size:24px;line-height:1.4;margin:28px 0 12px}
.doc h2{font-size:19px;margin:30px 0 10px;padding-left:10px;border-left:4px solid var(--navy);line-height:1.4}
.doc h3{font-size:16px;margin:20px 0 6px}
.doc p,.doc li{font-size:15.5px}
.doc table{border-collapse:collapse;width:100%;font-size:14.5px;margin:10px 0}
.doc td,.doc th{border:1px solid var(--line);padding:9px 10px;vertical-align:top;text-align:left}
.doc th{background:var(--soft);font-weight:600;width:28%}
.crumb{font-size:13px;color:var(--mute);margin-top:14px}
.crumb a{color:var(--mute);text-decoration:none}
.lead-box{background:var(--soft);border-radius:10px;padding:16px 18px;margin:0 0 18px;font-size:16px}
.ex{background:#fff;border:1px solid var(--line);border-left:4px solid var(--ok);border-radius:8px;padding:14px 16px;white-space:pre-wrap;font-size:15px;line-height:1.8;margin:8px 0 14px}
.ngok{display:grid;gap:10px}
.ngok .pair{border:1px solid var(--line);border-radius:8px;overflow:hidden}
.ngok .ng,.ngok .ok{padding:10px 14px;font-size:15px}
.ngok .ng{background:#fbf3f3;color:#7a2e2e}
.ngok .ok{background:#f1f8f3;color:#1d4f33}
.ngok .why{padding:8px 14px;font-size:13.5px;color:var(--mute);border-top:1px solid var(--line)}
.cta-box{background:var(--navy);color:#fff;border-radius:12px;padding:24px 20px;margin:30px 0}
.cta-box h3{margin:0 0 8px;font-size:19px}
.cta-box p{margin:0 0 14px;opacity:.9;font-size:15px}
.cta-box .btn{background:#fff;color:var(--navy);margin:0 8px 8px 0}
.cta-box .btn.o{background:transparent;color:#fff;border-color:#fff}
.tags a{display:inline-block;border:1px solid var(--line);border-radius:999px;padding:5px 12px;font-size:13.5px;text-decoration:none;margin:0 6px 8px 0;color:var(--navy)}
.cat h2{font-size:18px;margin:26px 0 8px}
@media(min-width:760px){
  .hero h1{font-size:40px}
  .ctas{grid-template-columns:1fr 1fr}
  .cards{grid-template-columns:repeat(3,1fr)}
  .links{grid-template-columns:repeat(3,1fr)}
  .cat .links{grid-template-columns:repeat(3,1fr)}
  .doc h1{font-size:30px}
}