/* 书童 — 移动优先全局样式 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --primary: #4f46e5;
  --primary-dark: #4338ca;
  --bg: #f8fafc;
  --surface: #fff;
  --text: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --radius: 8px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 16px;
  min-height: calc(100vh - 120px);
}

/* Header */
.header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0 16px;
}
.header-inner {
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  height: 56px;
  gap: 24px;
}
.logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
}
.nav { display: flex; gap: 16px; }
.nav a {
  color: var(--text);
  text-decoration: none;
  font-size: 14px;
}
.nav a:hover { color: var(--primary); }
.user-area {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 14px;
}
.user-area a { color: var(--primary); text-decoration: none; }

/* Footer */
.footer {
  text-align: center;
  padding: 16px;
  color: var(--text-muted);
  font-size: 13px;
  border-top: 1px solid var(--border);
}

/* Cards */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 16px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 16px;
  border: none;
  border-radius: var(--radius);
  font-size: 14px;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-outline {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
}
.btn-danger { background: #ef4444; color: #fff; }
.btn-sm { padding: 4px 12px; font-size: 13px; }

/* Forms */
.form-group { margin-bottom: 16px; }
.form-group label {
  display: block;
  margin-bottom: 4px;
  font-size: 14px;
  font-weight: 500;
}
.form-input {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 14px;
  transition: border-color 0.2s;
}
.form-input:focus {
  outline: none;
  border-color: var(--primary);
}

/* Table */
.table { width: 100%; border-collapse: collapse; font-size: 14px; }
.table th, .table td {
  padding: 10px 12px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.table th { font-weight: 600; color: var(--text-muted); }

/* Tags */
.tag {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 12px;
  background: #e0e7ff;
  color: var(--primary);
}
.tag-success { background: #dcfce7; color: #16a34a; }
.tag-warning { background: #fef3c7; color: #d97706; }
.tag-error { background: #fee2e2; color: #dc2626; }

/* Utilities */
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mb-2 { margin-bottom: 16px; }
.text-muted { color: var(--text-muted); font-size: 13px; }
.text-center { text-align: center; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.gap-2 { gap: 8px; }

/* Responsive */
@media (max-width: 640px) {
  .header-inner { gap: 12px; }
  .nav { gap: 8px; }
  .nav a { font-size: 13px; }
  .container { padding: 12px; }
  .table { font-size: 12px; }
  .table th, .table td { padding: 8px; }
}