:root{
  --navy:#14284b; --navy-2:#1f3a68; --gold:#c9a227; --gold-soft:#f6efd6;
  --bg:#f7f8fb; --card:#ffffff; --text:#1c2333; --muted:#5b6478; --line:#e3e7ef;
  --warn-bg:#fff6e0; --warn-line:#e9b949; --info-bg:#eaf2ff; --info-line:#7aa7ec;
  --radius:14px; --shadow:0 2px 10px rgba(20,40,75,.06);
  --font:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC","Source Han Sans SC",system-ui,-apple-system,"Segoe UI",sans-serif;
}
@media (prefers-color-scheme: dark){
  :root{
    --bg:#0f1522; --card:#172033; --text:#e6e9f0; --muted:#a5adbf; --line:#28324a;
    --gold-soft:#2b2615; --warn-bg:#2d2512; --warn-line:#b88a1e; --info-bg:#14223b; --info-line:#3e6bb3;
    --shadow:none;
  }
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:var(--font);background:var(--bg);color:var(--text);line-height:1.75;font-size:16px;-webkit-text-size-adjust:100%}
a{color:var(--navy-2)}
@media (prefers-color-scheme: dark){a{color:#8fb4ff}}
img{max-width:100%}
.wrap{max-width:1080px;margin:0 auto;padding:0 16px}

/* header */
.site-header{background:var(--navy);color:#fff;position:sticky;top:0;z-index:50;border-bottom:3px solid var(--gold)}
.site-header .wrap{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:60px}
.brand{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none;font-weight:700;line-height:1.2}
.brand-mark{width:36px;height:36px;border-radius:9px;background:var(--gold);color:var(--navy);display:grid;place-items:center;font-weight:800;font-size:15px;flex:none}
.brand small{display:block;font-weight:400;opacity:.75;font-size:12px}
.nav{display:flex;gap:2px;flex-wrap:wrap}
.nav a{color:#dfe6f3;text-decoration:none;padding:8px 10px;border-radius:8px;font-size:15px;white-space:nowrap}
.nav a:hover{background:rgba(255,255,255,.1);color:#fff}
.nav a[aria-current="page"]{background:rgba(201,162,39,.22);color:#fff}
.menu-btn{display:none;background:none;border:1px solid rgba(255,255,255,.35);color:#fff;border-radius:8px;padding:6px 12px;font-size:15px;font-family:inherit}
@media (max-width:900px){
  .menu-btn{display:block}
  .nav{display:none;position:absolute;left:0;right:0;top:100%;background:var(--navy);flex-direction:column;padding:8px 16px 16px;border-bottom:3px solid var(--gold)}
  .nav.open{display:flex}
  .nav a{padding:12px 8px;border-bottom:1px solid rgba(255,255,255,.08)}
}

/* hero */
.hero{background:linear-gradient(135deg,var(--navy) 0%,var(--navy-2) 100%);color:#fff;padding:56px 0 48px}
.hero h1{font-size:clamp(28px,5vw,42px);margin:0 0 8px;line-height:1.3}
.hero .fr{color:var(--gold);font-size:15px;letter-spacing:.5px;margin:0 0 16px}
.hero p.lead{font-size:18px;max-width:720px;opacity:.92;margin:0 0 24px}
.page-hero{background:var(--navy);color:#fff;padding:36px 0 28px}
.page-hero h1{margin:0;font-size:clamp(24px,4vw,34px);line-height:1.35}
.page-hero p{margin:6px 0 0;opacity:.85}
.btns{display:flex;gap:10px;flex-wrap:wrap}
.btn{display:inline-block;padding:10px 18px;border-radius:999px;text-decoration:none;font-weight:600;font-size:15px}
.btn-gold{background:var(--gold);color:var(--navy)}
.btn-ghost{border:1px solid rgba(255,255,255,.5);color:#fff}

/* layout */
main{padding:32px 0 56px}
section{margin:0 0 40px}
h2{font-size:clamp(21px,3vw,26px);margin:0 0 14px;padding-left:12px;border-left:5px solid var(--gold);line-height:1.4}
h3{font-size:18px;margin:18px 0 8px}
.grid{display:grid;gap:16px}
.g2{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}
.g3{grid-template-columns:repeat(auto-fit,minmax(240px,1fr))}
.g4{grid-template-columns:repeat(auto-fit,minmax(160px,1fr))}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:20px;box-shadow:var(--shadow)}
.card h3{margin-top:0}
.card .tag{display:inline-block;font-size:12px;background:var(--gold-soft);color:var(--text);padding:2px 8px;border-radius:999px;margin-bottom:6px}
a.card{text-decoration:none;color:inherit;display:block;transition:transform .15s,border-color .15s}
a.card:hover{transform:translateY(-2px);border-color:var(--gold)}
.stat{text-align:center}
.stat b{display:block;font-size:30px;color:var(--navy-2);line-height:1.2}
@media (prefers-color-scheme: dark){.stat b{color:var(--gold)}}
.stat span{color:var(--muted);font-size:14px}
.muted{color:var(--muted)}
.fr-term{font-size:.88em;color:var(--muted);font-style:italic}

.note{border-left:4px solid var(--info-line);background:var(--info-bg);padding:14px 16px;border-radius:10px;margin:16px 0}
.warn{border-left:4px solid var(--warn-line);background:var(--warn-bg);padding:14px 16px;border-radius:10px;margin:16px 0}
.note p,.warn p{margin:4px 0}

/* table */
.table-wrap{overflow-x:auto;-webkit-overflow-scrolling:touch;border:1px solid var(--line);border-radius:var(--radius);background:var(--card)}
table{border-collapse:collapse;width:100%}
@media (max-width:560px){th,td{padding:9px 10px;font-size:15px}th{white-space:normal}}
th,td{padding:11px 14px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top}
th{background:var(--gold-soft);font-weight:600;white-space:nowrap}
tr:last-child td{border-bottom:none}
td.num{text-align:right;white-space:nowrap;font-variant-numeric:tabular-nums}

/* timeline */
.timeline{list-style:none;margin:0;padding:0;position:relative}
.timeline:before{content:"";position:absolute;left:62px;top:6px;bottom:6px;width:2px;background:var(--line)}
.timeline li{display:grid;grid-template-columns:52px 1fr;gap:22px;padding:8px 0;position:relative}
.timeline li:before{content:"";position:absolute;left:57px;top:17px;width:12px;height:12px;border-radius:50%;background:var(--gold);border:2px solid var(--card)}
.timeline .yr{font-weight:700;color:var(--navy-2);text-align:right;font-variant-numeric:tabular-nums}
@media (prefers-color-scheme: dark){.timeline .yr{color:var(--gold)}}

/* steps */
.steps{counter-reset:s;list-style:none;padding:0;margin:0}
.steps li{counter-increment:s;position:relative;padding:4px 0 18px 52px}
.steps li:before{content:counter(s);position:absolute;left:0;top:2px;width:36px;height:36px;border-radius:50%;background:var(--navy);color:#fff;display:grid;place-items:center;font-weight:700}
.steps li h3{margin:4px 0 4px}

/* faq */
details{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:0 18px;margin-bottom:10px}
summary{cursor:pointer;padding:14px 0;font-weight:600;list-style:none}
summary::-webkit-details-marker{display:none}
summary:before{content:"＋";color:var(--gold);margin-right:8px;font-weight:700}
details[open] summary:before{content:"－"}
details > div{padding:0 0 14px}

/* calculator */
.calc label{display:flex;align-items:flex-start;gap:10px;padding:8px 0;border-bottom:1px dashed var(--line);cursor:pointer}
.calc label:last-child{border-bottom:none}
.calc input[type=checkbox],.calc input[type=radio]{margin-top:6px;accent-color:var(--navy-2);width:18px;height:18px;flex:none}
.calc .amt{margin-left:auto;white-space:nowrap;font-variant-numeric:tabular-nums;color:var(--muted)}
.calc select{font:inherit;padding:6px 10px;border-radius:8px;border:1px solid var(--line);background:var(--card);color:var(--text);max-width:100%}
.total-box{background:var(--navy);color:#fff;border-radius:var(--radius);padding:20px;position:sticky;top:76px}
.total-box .big{font-size:34px;font-weight:800;color:var(--gold);font-variant-numeric:tabular-nums}
.total-box ul{padding-left:18px;margin:10px 0 0;font-size:14px;opacity:.9}

/* glossary */
dl.gloss{display:grid;grid-template-columns:minmax(140px,max-content) 1fr;gap:8px 18px;margin:0}
dl.gloss dt{font-weight:600;font-style:italic}
dl.gloss dd{margin:0}
@media (max-width:560px){dl.gloss{grid-template-columns:1fr}dl.gloss dd{margin-bottom:8px}}

/* footer */
.site-footer{background:var(--navy);color:#c8d1e3;padding:32px 0;font-size:14px}
.site-footer a{color:#fff}
.site-footer .grid{gap:24px}
.site-footer h4{color:var(--gold);margin:0 0 8px;font-size:15px}
.disclaimer{border-top:1px solid rgba(255,255,255,.12);margin-top:22px;padding-top:16px;opacity:.8;font-size:13px}
ul.clean{padding-left:20px;margin:6px 0}
ul.clean li{margin:3px 0}
.calc label.sel{flex-wrap:wrap;justify-content:space-between}
.calc label.sel .amt{margin-left:0}
@media (max-width:900px){.total-box{position:static}}