:root {
  --bg: #f5f6f8;
  --card-bg: #ffffff;
  --border: #ddd;
  --border-soft: #eee;
  --text: #111827;
  --muted: #666;
  --nav-bg: #071a46;
  --nav-active: #2b7cff;
  --danger: #ef4444;
  --primary: #2b7cff;
}

body {
  font-family: Arial, "Microsoft YaHei", "PingFang SC", sans-serif;
  margin: 0;
  background: var(--bg);
  color: var(--text);
}

.layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  min-height: 100vh;
}

.side {
  background: var(--nav-bg);
  color: #fff;
  padding: 20px;
}

.side h2 {
  font-size: 20px;
  line-height: 1.3;
  margin: 0 0 28px;
  font-weight: 700;
}

.side a {
  display: block;
  color: #fff;
  text-decoration: none;
  padding: 12px;
  border-radius: 8px;
  margin-bottom: 8px;
  font-size: 16px;
  line-height: 1.4;
}

.side a.active,
.side a:hover {
  background: var(--nav-active);
}

.main {
  padding: 24px;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

input,
select,
textarea,
button {
  font-size: 14px;
}

.note {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
}

.muted {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.6;
}

.empty {
  color: #777;
  padding: 20px 0;
}

@media (max-width: 980px) {
  .layout {
    grid-template-columns: 1fr;
  }
}