:root {
  --bg: #0f172a;
  --card: #1e293b;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --danger: #f87171;
  --ok: #4ade80;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Segoe UI", system-ui, "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  font-size: 16px;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  padding: 1rem 2rem;
  background: var(--card);
  border-bottom: 1px solid #334155;
  flex-wrap: wrap;
}
.nav a { color: var(--muted); margin-right: 0.75rem; font-size: 1.05rem; }
.nav a:hover { color: var(--accent); }
.nav .brand { font-weight: 700; color: var(--text); margin-right: 1.5rem; font-size: 1.2rem; }
.wrap { max-width: 1300px; margin: 0 auto; padding: 2rem; }
.card {
  background: var(--card);
  border-radius: 10px;
  padding: 1.5rem;
  margin-bottom: 1.25rem;
  border: 1px solid #334155;
}
h1 { font-size: 1.75rem; margin: 0 0 1.25rem; }
table { width: 100%; border-collapse: collapse; font-size: 1rem; }
th, td { padding: 0.75rem 0.9rem; text-align: left; border-bottom: 1px solid #334155; }
th { color: var(--muted); font-weight: 600; font-size: 0.95rem; }
.btn {
  display: inline-block;
  padding: 0.5rem 1rem;
  border-radius: 6px;
  border: none;
  cursor: pointer;
  font-size: 1rem;
  background: #334155;
  color: var(--text);
  transition: all 0.2s;
}
.btn:hover { opacity: 0.9; }
.btn-primary { background: #2563eb; }
.btn-danger { background: #b91c1c; }
.btn-sm { padding: 0.3rem 0.6rem; font-size: 0.9rem; }
input[type="text"], input[type="password"], input[type="number"], input[type="date"], select, textarea {
  width: 100%;
  max-width: 400px;
  padding: 0.6rem 0.8rem;
  border-radius: 6px;
  border: 1px solid #475569;
  background: #0f172a;
  color: var(--text);
  font-size: 1rem;
}
textarea { max-width: 100%; min-height: 90px; }
.form-row { margin-bottom: 1rem; }
label { display: block; margin-bottom: 0.5rem; color: var(--muted); font-size: 0.95rem; }
.msg { padding: 0.8rem 1rem; border-radius: 6px; margin-bottom: 1.25rem; font-size: 1rem; }
.msg-ok { background: rgba(74, 222, 128, 0.15); color: var(--ok); }
.msg-err { background: rgba(248, 113, 113, 0.15); color: var(--danger); }
.stats { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 1rem; }
.stat { background: #0f172a; padding: 1rem; border-radius: 8px; border: 1px solid #334155; }
.stat .num { font-size: 1.75rem; font-weight: 700; color: var(--accent); margin-bottom: 0.25rem; }
.stat .lbl { font-size: 0.9rem; color: var(--muted); }
.login-box { max-width: 420px; margin: 5rem auto; padding: 2.5rem; }
.login-box h1 { text-align: center; font-size: 2rem; }