:root{
  --bg:#f7f8fa; --card:#ffffff; --ink:#1a2233; --muted:#5b6577;
  --line:#e3e7ee; --brand:#2563eb; --brand-dark:#1d4ed8;
  --ok:#15803d; --err:#dc2626; --radius:12px;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;background:var(--bg);color:var(--ink);line-height:1.55}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
header.site{background:var(--card);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:10}
header.site .wrap{max-width:1024px;margin:0 auto;padding:14px 20px;display:flex;align-items:center;justify-content:space-between;gap:16px}
.logo{font-weight:800;font-size:1.25rem;color:var(--ink)}
.logo span{color:var(--brand)}
.lang-toggle{background:#fff;color:var(--brand);border:1px solid var(--brand);border-radius:8px;padding:6px 14px;font-size:.88rem;font-weight:600;cursor:pointer;flex:none}
.lang-toggle:hover{background:#eff4ff}
nav.main a{margin-left:18px;color:var(--muted);font-size:.95rem}
nav.main a:hover{color:var(--brand);text-decoration:none}
main{max-width:1024px;margin:0 auto;padding:28px 20px 48px}
.hero{text-align:center;padding:26px 10px 10px}
.hero h1{font-size:2rem;margin:0 0 8px}
.hero p{color:var(--muted);max-width:640px;margin:0 auto}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px;margin-top:28px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:20px;transition:box-shadow .15s,transform .15s;display:block;color:var(--ink)}
.card:hover{box-shadow:0 8px 24px rgba(26,34,51,.08);transform:translateY(-2px);text-decoration:none}
.card .icon{font-size:1.7rem}
.card h2{font-size:1.1rem;margin:10px 0 6px}
.card p{color:var(--muted);font-size:.92rem;margin:0}
.tool-box{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px;margin-top:18px}
h1.page{font-size:1.6rem;margin:4px 0 6px}
p.lede{color:var(--muted);max-width:760px}
label{display:block;font-weight:600;font-size:.9rem;margin:14px 0 6px}
input[type=text],input[type=number],input[type=datetime-local],select,textarea{
  width:100%;padding:10px 12px;border:1px solid var(--line);border-radius:8px;font-size:1rem;background:#fff;color:var(--ink);font-family:inherit}
textarea{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.9rem;min-height:160px;resize:vertical}
.row{display:flex;gap:14px;flex-wrap:wrap}
.row>div{flex:1;min-width:180px}
button{background:var(--brand);color:#fff;border:0;border-radius:8px;padding:10px 18px;font-size:.95rem;cursor:pointer;font-weight:600}
button:hover{background:var(--brand-dark)}
button.ghost{background:#fff;color:var(--brand);border:1px solid var(--brand)}
button.ghost:hover{background:#eff4ff}
.btn-row{display:flex;gap:10px;flex-wrap:wrap;margin-top:16px}
table.result{width:100%;border-collapse:collapse;margin-top:16px}
table.result th,table.result td{border:1px solid var(--line);padding:9px 12px;text-align:left;font-size:.95rem}
table.result th{background:#f0f3f8;width:220px;font-weight:600}
td.mono,th.mono{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}
.msg{margin-top:14px;padding:10px 14px;border-radius:8px;font-size:.93rem;display:none}
.msg.ok{display:block;background:#ecfdf3;color:var(--ok);border:1px solid #bbe9c9}
.msg.err{display:block;background:#fef2f2;color:var(--err);border:1px solid #f5c6c6}
.stats{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:12px;margin-top:16px}
.stat{background:#f0f3f8;border-radius:10px;padding:14px;text-align:center}
.stat .num{font-size:1.5rem;font-weight:800}
.stat .lbl{color:var(--muted);font-size:.82rem}
footer.site{border-top:1px solid var(--line);background:var(--card);color:var(--muted);font-size:.88rem}
footer.site .wrap{max-width:1024px;margin:0 auto;padding:18px 20px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px}
.small{font-size:.85rem;color:var(--muted)}
#qrcode{display:inline-block;padding:12px;background:#fff;border:1px solid var(--line);border-radius:10px;margin-top:16px}
@media (max-width:600px){
  nav.main{display:none}
  .hero h1{font-size:1.55rem}
  table.result th{width:130px}
}