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

body {
  font-family: 'Microsoft YaHei', 'PingFang SC', sans-serif;
  background: linear-gradient(135deg, #0a1628 0%, #1a2a4a 50%, #0d1b2a 100%);
  min-height: 100vh;
  color: #fff;
  overflow-x: hidden;
}

.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 20px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* 头部样式 */
header {
  text-align: center;
  padding: 30px 0;
  border-bottom: 2px solid rgba(0, 150, 255, 0.3);
  margin-bottom: 30px;
}

header h1 {
  font-size: 2.5rem;
  background: linear-gradient(90deg, #00aaff, #00ffcc);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-shadow: 0 0 30px rgba(0, 170, 255, 0.5);
  margin-bottom: 20px;
}

/* 控制按钮 */
.controls {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 20px;
  margin-top: 20px;
}

.control-btn {
  padding: 12px 30px;
  font-size: 1rem;
  background: linear-gradient(135deg, #0066cc 0%, #0099ff 100%);
  border: none;
  border-radius: 8px;
  color: #fff;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(0, 150, 255, 0.3);
}

.control-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 150, 255, 0.5);
}

.control-btn:active {
  transform: translateY(0);
}

.page-indicator {
  font-size: 1.2rem;
  color: #00ccff;
  font-weight: bold;
}

/* 内容区域 */
.content {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

/* 班级卡片 */
.class-card {
  width: 100%;
  max-width: 1200px;
  background: rgba(20, 40, 80, 0.6);
  border-radius: 20px;
  padding: 40px;
  box-shadow: 0 10px 40px rgba(0, 100, 200, 0.3);
  border: 1px solid rgba(0, 150, 255, 0.2);
  backdrop-filter: blur(10px);
  animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.class-header {
  text-align: center;
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 2px solid rgba(0, 150, 255, 0.3);
}

.class-name {
  font-size: 2rem;
  color: #00ccff;
  font-weight: bold;
  text-shadow: 0 0 20px rgba(0, 200, 255, 0.5);
}

.class-stats {
  display: flex;
  justify-content: center;
  gap: 40px;
  margin-top: 15px;
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: bold;
  color: #00ffcc;
  text-shadow: 0 0 15px rgba(0, 255, 200, 0.5);
}

.stat-label {
  font-size: 0.9rem;
  color: #88ccff;
  margin-top: 5px;
}

/* 学生表格 */
.students-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 20px;
}

.students-table th {
  background: linear-gradient(135deg, #003366 0%, #006699 100%);
  padding: 15px;
  text-align: left;
  font-size: 1rem;
  color: #00ccff;
  border-bottom: 2px solid #0099ff;
}

.students-table td {
  padding: 12px 15px;
  border-bottom: 1px solid rgba(0, 150, 255, 0.1);
  font-size: 0.95rem;
}

.students-table tr:hover {
  background: rgba(0, 150, 255, 0.1);
}

.students-table tr:nth-child(even) {
  background: rgba(0, 100, 200, 0.05);
}

.status-badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 15px;
  font-size: 0.85rem;
  font-weight: bold;
}

.status-success {
  background: linear-gradient(135deg, #00cc66 0%, #00ff88 100%);
  color: #003322;
}

.status-pending {
  background: linear-gradient(135deg, #ff9900 0%, #ffcc00 100%);
  color: #332200;
}

/* 页脚 */
footer {
  text-align: center;
  padding: 20px 0;
  margin-top: 30px;
  border-top: 1px solid rgba(0, 150, 255, 0.2);
  color: #6699cc;
}

/* 加载动画 */
.loading {
  text-align: center;
  padding: 50px;
}

.loading-spinner {
  width: 50px;
  height: 50px;
  border: 4px solid rgba(0, 150, 255, 0.3);
  border-top-color: #00ccff;
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin: 0 auto 20px;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* 响应式设计 */
@media (max-width: 768px) {
  header h1 {
    font-size: 1.8rem;
  }

  .class-card {
    padding: 20px;
  }

  .class-name {
    font-size: 1.5rem;
  }

  .stat-number {
    font-size: 1.8rem;
  }

  .students-table {
    font-size: 0.85rem;
  }

  .students-table th,
  .students-table td {
    padding: 8px;
  }

  .controls {
    flex-wrap: wrap;
  }

  .control-btn {
    padding: 10px 20px;
    font-size: 0.9rem;
  }
}

/* 无数据提示 */
.no-data {
  text-align: center;
  padding: 50px;
  color: #6699cc;
  font-size: 1.2rem;
}