:root{
  --brand:#2b6bff;
  --bg:#f6f8fb;
  --muted:#6b7280;
  --card:#ffffff;
  --border:#e5e7eb;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,'PingFang SC','Hiragino Sans GB','Microsoft YaHei',sans-serif;background:var(--bg);color:#111}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
.container{max-width:1100px;margin:0 auto;padding:16px}

.topbar{position:sticky;top:0;z-index:50;background:#fff;border-bottom:1px solid var(--border)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;padding:12px 16px}
.logo{font-weight:800;color:var(--brand);font-size:20px}
.nav-links{display:flex;gap:18px;align-items:center}
.nav-links a{color:#111}
.nav-cta{padding:8px 12px;background:var(--brand);color:#fff;border-radius:8px}
.burger{display:none;background:none;border:0;font-size:24px;cursor:pointer}

@media (max-width: 900px){
  .nav-links{display:none;position:absolute;top:56px;right:12px;background:#fff;border:1px solid var(--border);border-radius:10px;box-shadow:0 10px 30px rgba(0,0,0,.08);padding:12px;flex-direction:column;min-width:180px}
  .nav-links.show{display:flex}
  .burger{display:block}
}

.hero{padding:36px 16px}
.hero h1{font-size:32px;margin:8px 0 12px}
.hero p{color:var(--muted);margin:0 0 18px}
.actions{display:flex;gap:12px;flex-wrap:wrap}
.btn{padding:10px 16px;border:0;border-radius:10px;background:var(--brand);color:#fff;cursor:pointer}
.btn.line{background:#fff;color:var(--brand);border:1px solid var(--brand)}

.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
@media (max-width: 900px){ .grid3{grid-template-columns:1fr} }
.card{background:var(--card);border:1px solid var(--border);border-radius:14px;padding:16px}
.card h3{margin:6px 0 8px}
.card p{color:var(--muted);margin:0}

.main{background:#fff;border:1px solid var(--border);border-radius:14px;padding:16px;margin:16px 0}
.input{width:100%;padding:12px 14px;border:1px solid var(--border);border-radius:10px}
.select{padding:10px 12px;border:1px solid var(--border);border-radius:10px;background:#fff}
.row{display:flex;gap:12px;align-items:center;margin:10px 0}
.row .grow{flex:1}

.table{width:100%;border-collapse:collapse}
.table th,.table td{padding:10px;border-bottom:1px solid var(--border);text-align:left;font-size:14px}
.tips{color:var(--muted);font-size:13px}

.footer{padding:24px 16px;color:var(--muted);text-align:center;border-top:1px solid var(--border);background:#fff;margin-top:26px}

.notice{padding:10px 12px;border-radius:10px;background:#f0f7ff;border:1px solid #cfe3ff;color:#194b9a}
.err{padding:10px 12px;border-radius:10px;background:#fff5f5;border:1px solid #ffd6d6;color:#9a1b1b}

.chat-wrap{display:flex;flex-direction:column;gap:12px}
.chat-q,.chat-a{padding:12px;border-radius:12px;max-width:880px}
.chat-q{background:#eef2ff;align-self:flex-end}
.chat-a{background:#f8fafc;align-self:flex-start;border:1px solid var(--border)}