:root{
  --bg:#f4f6fb; --card:#ffffff; --brand:#0f4c81; --brand2:#1d6fb8;
  --accent:#e8a33d; --text:#1c2733; --muted:#5b6b7b; --line:#e2e8f0;
  --ok:#1a7f4b; --warn:#c0392b; --soft:#eef3fa;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{font-family:"Segoe UI",-apple-system,Roboto,"Helvetica Neue",Arial,"PingFang SC","Microsoft YaHei","Malgun Gothic","Hiragino Sans",sans-serif;background:var(--bg);color:var(--text);line-height:1.5}
a{color:var(--brand2)}
.topbar{background:var(--brand);color:#fff;padding:14px 20px;display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap}
.topbar .brand{font-size:19px;font-weight:700;letter-spacing:.3px}
.topbar .brand small{display:block;font-weight:400;font-size:12px;opacity:.85}
.top-actions{display:flex;gap:10px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:8px;padding:9px 16px;border:none;border-radius:8px;font-size:14px;font-weight:600;cursor:pointer;text-decoration:none;transition:.15s}
.btn-home{background:var(--accent);color:#241a00}
.btn-home:hover{filter:brightness(1.05)}
.btn-mail{background:rgba(255,255,255,.16);color:#fff;border:1px solid rgba(255,255,255,.35)}
.btn-mail:hover{background:rgba(255,255,255,.26)}
.navwrap{background:var(--card);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.nav-inner{max-width:1000px;margin:0 auto;padding:8px 18px;display:flex;gap:6px;flex-wrap:wrap;align-items:center}
.nav-inner a{color:var(--text);text-decoration:none;font-size:14px;font-weight:600;padding:8px 14px;border-radius:8px}
.nav-inner a:hover{background:var(--soft)}
.nav-inner a.active{background:var(--brand);color:#fff}
/* Keep the sticky nav a single row on narrow screens so it never covers page controls. */
@media (max-width:760px){
  .nav-inner{flex-wrap:nowrap;overflow-x:auto}
  .nav-inner a{white-space:nowrap;flex:0 0 auto}
}
.container{max-width:1000px;margin:0 auto;padding:22px 18px 60px}
.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:20px;margin-bottom:16px;box-shadow:0 1px 2px rgba(16,40,70,.05)}
.card h2{margin:0 0 4px;font-size:18px;color:var(--brand)}
.card .sub{color:var(--muted);font-size:13px;margin:0 0 16px}
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:14px}
.field label{display:block;font-size:13px;font-weight:600;color:var(--muted);margin-bottom:5px}
.field input,.field select{width:100%;padding:10px 12px;font-size:15px;border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--text)}
.field input:focus,.field select:focus{outline:none;border-color:var(--brand2)}
.hint{font-size:11.5px;color:var(--muted);margin-top:4px}
.btn-calc{background:var(--brand);color:#fff;margin-top:14px;width:100%;padding:12px;border:none;border-radius:10px;font-size:15px;font-weight:700;cursor:pointer}
.btn-calc:hover{background:var(--brand2)}
.results{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:12px;margin-top:16px}
.result{background:var(--soft);border-left:4px solid var(--brand2);border-radius:8px;padding:12px 14px}
.result .k{font-size:12px;color:var(--muted);font-weight:600}
.result .v{font-size:22px;font-weight:700;color:var(--brand);margin-top:2px}
.result .u{font-size:12px;color:var(--muted)}
.result.flag .v{color:var(--warn)}
.table-wrap{overflow-x:auto}
table{width:100%;border-collapse:collapse;font-size:13px}
th,td{border:1px solid var(--line);padding:8px 10px;text-align:left}
th{background:var(--soft);color:var(--brand)}
td.num{text-align:right;font-variant-numeric:tabular-nums}
tr:nth-child(even) td{background:#fafcff}
.tool-list{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:16px}
.tool-card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:20px;text-decoration:none;color:var(--text);transition:.15s}
.tool-card:hover{border-color:var(--brand2);box-shadow:0 4px 14px rgba(16,40,70,.12)}
.tool-card h3{margin:0 0 6px;color:var(--brand);font-size:17px}
.tool-card p{margin:0;color:var(--muted);font-size:13.5px}
.disclaimer{background:#fff7ec;border:1px solid #f3d9a4;border-left:5px solid var(--accent);border-radius:10px;padding:14px 16px;font-size:13px;color:#5b4a1e;margin-top:18px}
.footer{text-align:center;color:var(--muted);font-size:12.5px;margin-top:22px}
.footer a{color:var(--brand2)}
.note-banner{font-size:12.5px;color:var(--muted);background:var(--soft);border-radius:8px;padding:8px 12px;margin-bottom:14px}
#langSel{font-size:14px;padding:8px 10px;border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--text)}

/* ---- Dynamic multi-segment table (friction page) ---- */
.seg-table{width:100%;border-collapse:collapse;font-size:13px}
.seg-table th{background:var(--soft);color:var(--brand);text-align:left;padding:8px}
.seg-table td{padding:6px;border-top:1px solid var(--line)}
.seg-table input{width:100%;min-width:70px;padding:8px 10px;font-size:14px;border:1px solid var(--line);border-radius:7px;background:#fff;color:var(--text)}
.seg-table input:focus{outline:none;border-color:var(--brand2)}
.btn-mini{background:var(--soft);border:1px solid var(--line);color:var(--muted);border-radius:7px;padding:6px 10px;font-size:13px;font-weight:600;cursor:pointer}
.btn-mini:hover{background:var(--line)}
.btn-add{background:var(--brand);color:#fff;border:none;border-radius:8px;padding:9px 14px;font-size:14px;font-weight:600;cursor:pointer;margin-top:10px}
.btn-add:hover{background:var(--brand2)}
.btn-export{background:#fff;color:var(--brand);border:2px solid var(--brand);border-radius:10px;padding:11px 18px;font-size:14px;font-weight:700;cursor:pointer;width:100%}
.btn-export:hover{background:var(--soft)}
.seg-note{font-size:11.5px;color:var(--muted);margin-top:6px}
.sum-row{background:#fafcff}