:root{
  --blue:#2563eb;
  --blue-dark:#1d4ed8;
  --bg:#f6f8fb;
  --card-bg:#ffffff;
  --border:#e4e9f0;
  --text:#1e293b;
  --muted:#64748b;
  --hero-bg:#eef2f9;
  --radius:12px;
}
*{box-sizing:border-box;}
body{
  margin:0;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background:var(--bg);
  color:var(--text);
}
a{color:inherit;text-decoration:none;}

/* Header */
header.site-header{
  display:flex;align-items:center;justify-content:space-between;
  padding:16px 40px;background:#fff;border-bottom:1px solid var(--border);
}
.brand{display:flex;align-items:center;gap:12px;}
.brand-icon{width:36px;height:36px;color:var(--blue);}
.brand h1{font-size:24px;font-weight:800;color:var(--blue);margin:0;}
.brand p{font-size:12px;color:var(--muted);margin:0;}
nav.main-nav{display:flex;gap:28px;font-size:14px;font-weight:500;}
nav.main-nav a.active{color:var(--blue);border-bottom:2px solid var(--blue);padding-bottom:4px;}

/* Hero */
.hero{background:var(--hero-bg);padding:48px 40px;display:flex;justify-content:space-between;align-items:center;}
.hero h2{font-size:38px;margin:0 0 12px 0;}
.hero p{color:var(--muted);max-width:520px;margin:0;font-size:15px;}
.hero svg{width:110px;height:110px;color:#94a3b8;}

/* Content */
main{padding:40px;max-width:1200px;margin:0 auto;}
.section-title h3{font-size:24px;margin:0 0 4px 0;}
.section-title p{color:var(--muted);margin:0 0 24px 0;font-size:14px;}

.grid{display:grid;grid-template-columns:1fr 1fr;gap:16px;}
@media(max-width:720px){.grid{grid-template-columns:1fr;}header.site-header{padding:16px;}main{padding:20px;}.hero{flex-direction:column;align-items:flex-start;gap:20px;padding:32px 20px;}}

.card{
  display:flex;align-items:center;gap:16px;
  background:var(--card-bg);border:1px solid var(--border);border-radius:var(--radius);
  padding:20px;transition:box-shadow .15s ease, transform .15s ease;
}
a.card:hover{box-shadow:0 4px 14px rgba(30,41,59,.08);transform:translateY(-1px);}
.card-icon{width:44px;height:44px;border-radius:10px;display:flex;align-items:center;justify-content:center;flex-shrink:0;}
.card-icon svg{width:22px;height:22px;}
.card-text h4{margin:0 0 4px 0;font-size:16px;}
.card-text p{margin:0;font-size:13px;color:var(--muted);}
.card-arrow{margin-left:auto;color:var(--muted);}

.card.disabled{
  opacity:.55;cursor:not-allowed;background:#fafbfc;
}
.card.disabled:hover{box-shadow:none;transform:none;}
.card.disabled .card-icon{filter:grayscale(1);}
.badge-soon{
  margin-left:auto;font-size:11px;font-weight:600;color:var(--muted);
  background:#e9edf3;padding:4px 9px;border-radius:999px;white-space:nowrap;
}

.tip-box{
  margin-top:24px;display:flex;gap:12px;align-items:flex-start;
  background:#eef2f9;border-radius:var(--radius);padding:16px 20px;color:var(--text);font-size:14px;
}
.tip-box svg{width:20px;height:20px;color:var(--blue);flex-shrink:0;margin-top:2px;}

/* Tool page */
.tool-page{max-width:720px;margin:0 auto;padding:40px 20px;}
.tool-page h2{font-size:26px;margin-bottom:4px;}
.tool-page .desc{color:var(--muted);margin-bottom:24px;font-size:14px;}
.tool-box{background:var(--card-bg);border:1px solid var(--border);border-radius:var(--radius);padding:24px;}
.field{margin-bottom:16px;}
.field label{display:block;font-size:13px;font-weight:600;margin-bottom:6px;color:var(--text);}
.field input,.field select{
  width:100%;padding:10px 12px;border:1px solid var(--border);border-radius:8px;font-size:14px;
}
.btn{
  background:var(--blue);color:#fff;border:none;padding:10px 20px;border-radius:8px;
  font-size:14px;font-weight:600;cursor:pointer;
}
.btn:hover{background:var(--blue-dark);}
.btn-row{display:flex;gap:10px;flex-wrap:wrap;}

.result{margin-top:20px;}
.result-row{
  display:flex;justify-content:space-between;padding:10px 0;border-bottom:1px solid var(--border);font-size:14px;
}
.result-row:last-child{border-bottom:none;}
.result-row .k{color:var(--muted);}
.result-row .v{font-weight:600;font-family:ui-monospace,Menlo,Consolas,monospace;}

.error{color:#dc2626;font-size:13px;margin-top:10px;}
.note-box{
  background:#fff7ed;border:1px solid #fed7aa;color:#9a3412;border-radius:10px;padding:14px 16px;font-size:13px;margin-top:16px;
}
.placeholder-box{
  background:#f1f5f9;border:1px dashed #cbd5e1;border-radius:10px;padding:24px;text-align:center;color:var(--muted);font-size:14px;
}
.back-link{display:inline-block;margin-bottom:20px;font-size:13px;color:var(--blue);}

footer.site-footer{
  border-top:1px solid var(--border);padding:20px 40px;display:flex;justify-content:space-between;
  font-size:13px;color:var(--muted);
}
footer.site-footer .f-links{display:flex;gap:20px;}