* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  background-color: #f0f2f5;
  color: #333;
  height: 100vh;
  overflow: hidden;
}

.layout {
  display: flex;
  height: 100vh;
}

.sidebar {
  width: 240px;
  background: linear-gradient(180deg, #1e3c72 0%, #2a5298 100%);
  color: #fff;
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
}

.sidebar-header {
  padding: 24px 20px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

.sidebar-header h1 {
  font-size: 20px;
  font-weight: 600;
  letter-spacing: 1px;
}

.sidebar-header p {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.7);
  margin-top: 6px;
}

.nav {
  flex: 1;
  padding: 12px 0;
  overflow-y: auto;
}

.nav-item {
  padding: 12px 24px;
  cursor: pointer;
  font-size: 14px;
  transition: all 0.2s;
  border-left: 3px solid transparent;
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-item:hover {
  background: rgba(255, 255, 255, 0.08);
}

.nav-item.active {
  background: rgba(255, 255, 255, 0.15);
  border-left-color: #ffd700;
  font-weight: 500;
}

.nav-item .icon {
  font-size: 16px;
  width: 20px;
  text-align: center;
}

.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.top-bar {
  height: 56px;
  background: #fff;
  border-bottom: 1px solid #e8e8e8;
  display: flex;
  align-items: center;
  padding: 0 24px;
  font-size: 16px;
  font-weight: 500;
  color: #1e3c72;
  flex-shrink: 0;
}

.page-container {
  flex: 1;
  padding: 24px;
  overflow-y: auto;
}

.page {
  display: none;
}

.page.active {
  display: block;
}

.card {
  background: #fff;
  border-radius: 8px;
  padding: 24px;
  margin-bottom: 20px;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.06);
}

.card-title {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 16px;
  color: #1e3c72;
  padding-bottom: 12px;
  border-bottom: 1px solid #f0f0f0;
}

.form-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.form-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

.form-group label {
  font-size: 14px;
  color: #555;
  white-space: nowrap;
}

input[type="number"],
input[type="text"] {
  padding: 8px 12px;
  border: 1px solid #d9d9d9;
  border-radius: 4px;
  font-size: 14px;
  width: 140px;
  outline: none;
  transition: border-color 0.2s;
}

input[type="number"]:focus,
input[type="text"]:focus {
  border-color: #2a5298;
}

.btn {
  padding: 8px 20px;
  border: none;
  border-radius: 4px;
  font-size: 14px;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-primary {
  background: #2a5298;
  color: #fff;
}

.btn-primary:hover {
  background: #1e3c72;
}

.btn-default {
  background: #fff;
  color: #555;
  border: 1px solid #d9d9d9;
}

.btn-default:hover {
  border-color: #2a5298;
  color: #2a5298;
}

.table-wrapper {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

thead th {
  background: #fafafa;
  padding: 12px 16px;
  text-align: left;
  font-weight: 600;
  color: #333;
  border-bottom: 2px solid #f0f0f0;
  white-space: nowrap;
}

tbody td {
  padding: 12px 16px;
  border-bottom: 1px solid #f0f0f0;
  color: #555;
}

tbody tr:hover {
  background: #fafbfc;
}

.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 16px 0 4px;
}

.pagination .page-info {
  margin-right: 16px;
  color: #888;
  font-size: 13px;
}

.pagination button {
  min-width: 32px;
  height: 32px;
  padding: 0 10px;
  border: 1px solid #d9d9d9;
  background: #fff;
  border-radius: 4px;
  cursor: pointer;
  font-size: 13px;
  color: #555;
}

.pagination button:hover:not(:disabled) {
  border-color: #2a5298;
  color: #2a5298;
}

.pagination button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.pagination button.active {
  background: #2a5298;
  border-color: #2a5298;
  color: #fff;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
}

.stat-card {
  background: #fff;
  border-radius: 8px;
  padding: 20px;
  text-align: center;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.06);
  border-top: 3px solid #2a5298;
}

.stat-card .stat-label {
  font-size: 13px;
  color: #888;
  margin-bottom: 8px;
}

.stat-card .stat-value {
  font-size: 28px;
  font-weight: 600;
  color: #1e3c72;
}

.stat-card.male {
  border-top-color: #1890ff;
}
.stat-card.female {
  border-top-color: #eb2f96;
}
.stat-card.total {
  border-top-color: #52c41a;
}

.chart-container {
  width: 100%;
  height: 400px;
}

.loading {
  text-align: center;
  padding: 40px;
  color: #999;
}

.empty {
  text-align: center;
  padding: 40px;
  color: #999;
}

.toast {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%);
  padding: 12px 24px;
  border-radius: 4px;
  font-size: 14px;
  z-index: 9999;
  animation: slideDown 0.3s ease;
}

.toast.success {
  background: #52c41a;
  color: #fff;
}

.toast.error {
  background: #ff4d4f;
  color: #fff;
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translate(-50%, -20px);
  }
  to {
    opacity: 1;
    transform: translate(-50%, 0);
  }
}