body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  line-height: 1.6;
  margin: 0;
  padding: 0;
  background-color: #f5f5f5;
}

/* 修改导航栏样式 */
nav {
  background: #2c3e50;
  padding: 0.5rem 1rem;  /* 减小padding */
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

nav a {
  color: rgba(255,255,255,0.8) !important;  /* 调整链接颜色 */
  text-decoration: none;
  padding: 0.35rem 1rem;  /* 减小padding */
  margin: 0 0.25rem;  /* 减小margin */
  border-radius: 4px;
  transition: background-color 0.3s;
}

nav a:hover {
  background-color: rgba(255,255,255,0.1);
  color: #fff !important;
}

main {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1rem;
}

table {
  border-collapse: collapse;
  width: 100%;
  background: white;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  margin: 1rem 0;
}

th, td {
  border: 1px solid #ddd;
  padding: 12px;
  text-align: left;
}

th {
  background-color: #f8f9fa;
}

.sidebar-nav {
  margin-top: 20px;
  padding: 0;
  list-style: none;
}

/* 课程卡片相关样式 */
.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  padding: 1rem 0;
}

.course-card {
  background: white;
  border-radius: 10px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: transform 0.2s, box-shadow 0.2s;
  overflow: hidden;
}

.course-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.12);
}

.course-card__header {
  padding: 1rem;
  background: #f8f9fa;
  border-bottom: 1px solid #eee;
}

.course-card__title {
  margin: 0;
  font-size: 1.1rem;
  color: #2c3e50;
}

.course-card__body {
  padding: 1rem;
}

.course-card__info {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.course-card__info-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: #6c757d;
  font-size: 0.9rem;
}

.course-card__footer {
  padding: 1rem;
  background: #f8f9fa;
  border-top: 1px solid #eee;
  display: flex;
  justify-content: flex-end;
  gap: 0.5rem;
}

.preference-badge {
  padding: 0.4em 0.8em;
  font-size: 0.85em;
  font-weight: normal;
  border-radius: 20px;
}

.priority-star {
  color: #ffc107;
  font-size: 0.85em;
}

/* 课程标签样式 */
.course-tag {
  display: inline-block;
  padding: 0.35rem 0.75rem;
  background: #f0f7ff;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  margin: 0.2rem;
  border: 1px solid #cce5ff;
  font-size: 0.85rem;
  color: #0d6efd;
  transition: all 0.2s ease;
}

.course-tag:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 6px rgba(0,0,0,0.08);
}

.course-tag .priority-indicator {
  color: #ffc107;
  margin-left: 0.5rem;
}

.timeslot-tag {
  background: #f8f9fa;
  border: 1px solid #e9ecef;
  color: #495057;
}

.timeslot-tag.high-priority {
  background: #fff3cd;
  border-color: #ffeeba;
  color: #856404;
}

/* 时间格子视图样式 */
.timeslot-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);  /* 保持4列 */
  grid-template-rows: repeat(2, 1fr);     /* 2行对应周六周日 */
  gap: 6px;                               /* 稍微增加间距 */
  max-width: 280px;                       /* 适当调整宽度 */
  margin: 0.5rem 0;
}

.timeslot-cell {
  position: relative;
  padding: 4px 6px;  /* 减小垂直padding */
  border-radius: 4px;
  background: #e9ecef;
  cursor: pointer;
  text-align: center;
  font-size: 0.75rem;
  aspect-ratio: 2/1;  /* 修改为2:1的宽高比，使格子更扁平 */
  min-height: 28px;
}

.timeslot-cell.active {
  background: #4CAF50;
  color: white;
}

timeslot-cell.priority-2 {
  background: #2196F3;
  color: white;
}

.timeslot-cell.priority-3 {
  background: #FFC107;
  color: white;
}

.timeslot-tooltip {
  position: absolute;
  background: rgba(0, 0, 0, 0.8);
  color: white;
  padding: 4px 8px;
  border-radius: 4px;
  font-size: 0.75rem;
  bottom: 130%;  /* 稍微调高tooltip的位置 */
  left: 50%;
  transform: translateX(-50%);
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  transition: all 0.2s;
  z-index: 1000;
}

.timeslot-cell:hover .timeslot-tooltip {
  opacity: 1;
  visibility: visible;
}

/* 表格样式优化 */
.table {
  --bs-table-striped-bg: #f8f9fa;
}

.table > :not(caption) > * > * {
  padding: 1rem;
  vertical-align: middle;
}

.table thead th {
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.85rem;
  letter-spacing: 0.5px;
  background: #f1f4f6;
  border-bottom: 2px solid #e9ecef;
}

/* 卡片通用样式 */
.card {
  border: none;
  transition: box-shadow 0.3s ease;
}

.card:hover {
  box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.08);
}

.card-header {
  background: linear-gradient(to right, #f8f9fa, #fff);
  border-bottom: 1px solid #edf2f7;
  padding: 1rem;
}

/* 按钮样式优化 */
.btn {
  font-weight: 500;
  letter-spacing: 0.3px;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  transition: all 0.2s ease;
}

.btn-sm {
  padding: 0.25rem 0.75rem;
  font-size: 0.875rem;
}

.btn-outline-primary {
  border-width: 1.5px;
}

.btn-outline-primary:hover {
  background: rgba(13, 110, 253, 0.1);
  color: #0d6efd;
}

.btn-outline-danger {
  border-width: 1.5px;
}

.btn-outline-danger:hover {
  background: rgba(220, 53, 69, 0.1);
  color: #dc3545;
}

.btn-outline-info {
  color: #0dcaf0;
}

.btn-outline-info:hover {
  background: rgba(13, 202, 240, 0.1);
  color: #0dcaf0;
}

/* 实心按钮样式 */
.btn-primary {
  background-color: #0d6efd;
  color: white;
  border: none;
}

.btn-primary:hover {
  background-color: #0b5ed7;
  color: white;
}

.action-buttons .btn-primary {
  background-color: #0d6efd !important;
  color: white !important;
  border: none;
}

.action-buttons .btn-primary:hover {
  background-color: #0b5ed7 !important;
  color: white !important;
}

/* 按钮样式 - 专门针对操作按钮 */
.action-buttons .btn.btn-primary {
  background-color: #0d6efd;
  color: white;
  border: none;
}

.action-buttons .btn.btn-primary:hover {
  background-color: #0b5ed7;
  color: white;
}

/* 操作按钮组样式 */
.action-buttons {
  display: flex;
  gap: 0.3rem;
  justify-content: flex-end;
  align-items: center;
}

.action-buttons .btn-group {
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  border-radius: 4px;
  overflow: hidden;
}

.action-buttons .btn {
  border: none;
  padding: 0.4rem 0.8rem;
  font-size: 0.85rem;
  margin: 0;
}

.action-buttons .btn:first-child {
  border-right: 1px solid rgba(0,0,0,0.1);
}

/* 软色调按钮样式 */
.btn-soft-primary {
  color: #0d6efd;
  background: #f0f7ff;
  border: 1px solid #cce5ff;
  padding: 0.5rem 1.2rem;
  font-weight: 500;
}

.btn-soft-primary:hover {
  color: #0d6efd;
  background: #e3f2fd;
  border-color: #90caf9;
  transform: translateY(-1px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.05);
}

.login-page {
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #f5f5f5;
}

.login-container {
  width: 100%;
  max-width: 400px;
  padding: 2rem;
  background: white;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

.login-form {
  margin-top: 2rem;
}

.user-controls {
  display: flex;
  align-items: center;
}

.user-info {
  color: white;
  margin-right: 1rem;
}

.nav-links {
  flex: 1;
  display: flex;
  gap: 1rem;
}

.error-container {
  text-align: center;
  padding: 2rem;
  max-width: 600px;
  margin: 2rem auto;
}

.error-container h1 {
  font-size: 3rem;
  color: #dc3545;
  margin-bottom: 1rem;
}

.error-container h2 {
  font-size: 1.5rem;
  color: #6c757d;
  margin-bottom: 2rem;
}

.error-stack {
  background: #f8f9fa;
  padding: 1rem;
  border-radius: 4px;
  text-align: left;
  margin: 1rem 0;
  overflow-x: auto;
}

.error-actions {
  margin-top: 2rem;
}