:root {
  /* ===== 颜色系统 ===== */
  --bg-primary: #f7f6f3;
  --bg-secondary: #ffffff;
  --bg-hover: #f1f1ef;
  --bg-active: #e9e9e7;
  
  --text-primary: #37352f;
  --text-secondary: #787774;
  --text-tertiary: #9b9a97;
  --text-inverse: #ffffff;
  
  --border-default: #e9e9e7;
  --border-hover: #d3d3d1;
  
  /* 品牌色 */
  --brand-blue: #2383e2;
  --brand-blue-hover: #1a6dc5;
  --brand-green: #0f7b6c;
  --brand-orange: #d9730d;
  --brand-red: #e03e3e;
  
  /* 状态色 */
  --success-bg: #dbf6e0;
  --success-text: #1e7f34;
  --warning-bg: #fdecc8;
  --warning-text: #8b5c00;
  --error-bg: #ffe2dd;
  --error-text: #c62b40;
  
  /* ===== 间距系统 ===== */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-6: 24px;
  --space-8: 32px;
  
  /* ===== 圆角系统 ===== */
  --radius-sm: 3px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;
  
  /* ===== 阴影系统 ===== */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 4px 16px rgba(0, 0, 0, 0.08);
  
  /* ===== 排版系统 ===== */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-xs: 12px;
  --font-sm: 14px;
  --font-base: 15px;
  --font-lg: 16px;
  --font-xl: 18px;
  --font-2xl: 22px;
  --font-3xl: 28px;
  
  /* ===== 过渡 ===== */
  --transition-fast: 120ms ease;
  --transition-base: 200ms ease;
}

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

body {
  font-family: var(--font-family);
  font-size: var(--font-base);
  line-height: 1.5;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ===== SVG 图标系统 ===== */
.icon {
  width: 20px;
  height: 20px;
  display: inline-block;
  flex-shrink: 0;
  color: currentColor;
}

.icon-sm {
  width: 16px;
  height: 16px;
}

.icon-lg {
  width: 24px;
  height: 24px;
}

/* ===== 布局系统 ===== */
.app-container {
  display: flex;
  min-height: 100vh;
}

/* 侧边栏 - PC */
.sidebar {
  width: 240px;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-default);
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: 100;
  transition: transform var(--transition-base);
}

.sidebar-header {
  padding: var(--space-6) var(--space-4);
  border-bottom: 1px solid var(--border-default);
}

.sidebar-logo {
  font-size: var(--font-xl);
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.sidebar-nav {
  flex: 1;
  padding: var(--space-4) var(--space-2);
  overflow-y: auto;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2) var(--space-2);
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: var(--font-sm);
  font-weight: 500;
  transition: all var(--transition-fast);
  cursor: pointer;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
}

.nav-item:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.nav-item.active {
  background: var(--bg-active);
  color: var(--text-primary);
}

/* 主内容区 */
.main-content {
  flex: 1;
  margin-left: 240px;
  padding: var(--space-6) var(--space-6) 80px;
  min-width: 0;
}

.page-header {
  margin-bottom: var(--space-6);
}

.page-title {
  font-size: var(--font-2xl);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-1);
}

.page-subtitle {
  font-size: var(--font-sm);
  color: var(--text-secondary);
}

/* ===== 组件：卡片 ===== */
.card {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-default);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

.card-header {
  padding: var(--space-4) var(--space-4) var(--space-3);
  border-bottom: 1px solid var(--border-default);
}

.card-title {
  font-size: var(--font-base);
  font-weight: 600;
  color: var(--text-primary);
}

.card-body {
  padding: var(--space-4);
}

/* ===== 组件：统计卡片 ===== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-4);
  margin-bottom: var(--space-6);
}

.stat-card {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-default);
  padding: var(--space-4);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-fast);
}

.stat-card:hover {
  box-shadow: var(--shadow-md);
}

.stat-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-3);
}

.stat-icon.blue { background: rgba(35, 131, 226, 0.1); color: var(--brand-blue); }
.stat-icon.green { background: rgba(15, 123, 108, 0.1); color: var(--brand-green); }
.stat-icon.orange { background: rgba(217, 115, 13, 0.1); color: var(--brand-orange); }
.stat-icon.red { background: rgba(224, 62, 62, 0.1); color: var(--brand-red); }

.stat-value {
  font-size: var(--font-3xl);
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.2;
  margin-bottom: var(--space-1);
}

.stat-label {
  font-size: var(--font-sm);
  color: var(--text-secondary);
}

.stat-change {
  font-size: var(--font-xs);
  margin-top: var(--space-2);
}

.stat-change.up { color: var(--brand-green); }
.stat-change.down { color: var(--brand-red); }

/* ===== 组件：按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  font-size: var(--font-sm);
  font-weight: 500;
  line-height: 1.4;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  font-family: inherit;
}

.btn-primary {
  background: var(--brand-blue);
  color: var(--text-inverse);
}

.btn-primary:hover {
  background: var(--brand-blue-hover);
}

.btn-secondary {
  background: var(--bg-secondary);
  border-color: var(--border-default);
  color: var(--text-primary);
}

.btn-secondary:hover {
  background: var(--bg-hover);
  border-color: var(--border-hover);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}

.btn-ghost:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.btn-sm {
  padding: var(--space-1) var(--space-2);
  font-size: var(--font-xs);
}

.btn-lg {
  padding: var(--space-3) var(--space-6);
  font-size: var(--font-base);
}

/* ===== 组件：徽章 ===== */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 6px;
  font-size: var(--font-xs);
  font-weight: 500;
  border-radius: var(--radius-sm);
  line-height: 1.4;
}

.badge-blue {
  background: rgba(35, 131, 226, 0.1);
  color: var(--brand-blue);
}

.badge-green {
  background: rgba(15, 123, 108, 0.1);
  color: var(--brand-green);
}

.badge-orange {
  background: rgba(217, 115, 13, 0.1);
  color: var(--brand-orange);
}

.badge-red {
  background: rgba(224, 62, 62, 0.1);
  color: var(--brand-red);
}

.badge-gray {
  background: var(--bg-active);
  color: var(--text-secondary);
}

/* ===== 组件：任务列表 ===== */
.task-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.task-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3);
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-default);
  transition: all var(--transition-fast);
}

.task-item:hover {
  border-color: var(--border-hover);
  box-shadow: var(--shadow-sm);
}

.task-checkbox {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 2px solid var(--border-default);
  cursor: pointer;
  flex-shrink: 0;
  margin-top: 2px;
  transition: all var(--transition-fast);
  position: relative;
}

.task-checkbox:hover {
  border-color: var(--brand-green);
  background: var(--success-bg);
}

.task-item.completed .task-checkbox {
  background: var(--brand-green);
  border-color: var(--brand-green);
}

.task-item.completed .task-checkbox::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 10px;
  height: 10px;
  background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='white'%3E%3Cpath d='M9 16.17L4.83 12l-1.42 1.41L9 19 21 7l-1.41-1.41L9 16.17z'/%3E%3C/svg%3E") center/contain no-repeat;
}

.task-content {
  flex: 1;
  min-width: 0;
}

.task-title {
  font-size: var(--font-base);
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 2px;
}

.task-item.completed .task-title {
  text-decoration: line-through;
  color: var(--text-tertiary);
}

.task-meta {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.task-due {
  font-size: var(--font-xs);
  color: var(--text-secondary);
}

.task-due.overdue {
  color: var(--brand-red);
}

.task-actions {
  display: flex;
  gap: var(--space-1);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.task-item:hover .task-actions {
  opacity: 1;
}

.task-action-btn {
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  cursor: pointer;
  border: none;
  background: none;
  transition: all var(--transition-fast);
}

.task-action-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

/* ===== 组件：进度项目卡片 ===== */
.progress-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-4);
}

.progress-card {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-default);
  padding: var(--space-4);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-fast);
}

.progress-card:hover {
  box-shadow: var(--shadow-md);
}

.progress-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: var(--space-3);
}

.progress-name {
  font-size: var(--font-lg);
  font-weight: 600;
  color: var(--text-primary);
}

.progress-meta {
  font-size: var(--font-xs);
  color: var(--text-secondary);
  margin-top: 2px;
}

.progress-bar-container {
  height: 8px;
  background: var(--bg-active);
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: var(--space-2);
}

.progress-bar {
  height: 100%;
  border-radius: 999px;
  transition: width 0.3s ease;
}

.progress-bar.blue { background: var(--brand-blue); }
.progress-bar.green { background: var(--brand-green); }
.progress-bar.orange { background: var(--brand-orange); }
.progress-bar.red { background: var(--brand-red); }

.progress-stats {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.progress-percent {
  font-size: var(--font-sm);
  font-weight: 600;
}

.progress-percent.blue { color: var(--brand-blue); }
.progress-percent.green { color: var(--brand-green); }

/* ===== 组件：习惯打卡卡片 ===== */
.habits-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-4);
}

.habit-card {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-default);
  padding: var(--space-4);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-fast);
}

.habit-card:hover {
  box-shadow: var(--shadow-md);
}

.habit-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-3);
}

.habit-name {
  font-size: var(--font-base);
  font-weight: 600;
  color: var(--text-primary);
}

.habit-streak {
  font-size: var(--font-sm);
  font-weight: 600;
  color: var(--brand-orange);
}

.habit-streak-dots {
  display: flex;
  gap: 3px;
  margin-bottom: var(--space-3);
}

.streak-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--bg-active);
}

.streak-dot.done {
  background: var(--brand-green);
}

.streak-dot.today {
  box-shadow: 0 0 0 2px var(--brand-orange);
}

.habit-checkin-btn {
  width: 100%;
  padding: var(--space-2);
  background: var(--success-bg);
  color: var(--success-text);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  font-size: var(--font-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.habit-checkin-btn:hover {
  background: var(--brand-green);
  color: white;
}

.habit-checkin-btn.checked {
  background: var(--brand-green);
  color: white;
}

/* ===== 组件：日历热力图 ===== */
.calendar-heatmap {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.calendar-week {
  display: flex;
  gap: 2px;
}

.calendar-day {
  width: 12px;
  height: 12px;
  border-radius: 2px;
  background: var(--bg-active);
}

.calendar-day.level-1 { background: rgba(15, 123, 108, 0.2); }
.calendar-day.level-2 { background: rgba(15, 123, 108, 0.4); }
.calendar-day.level-3 { background: rgba(15, 123, 108, 0.6); }
.calendar-day.level-4 { background: rgba(15, 123, 108, 0.8); }
.calendar-day.today { outline: 2px solid var(--brand-orange); }

/* ===== 组件：浮动操作按钮（移动端） ===== */
.fab {
  position: fixed;
  right: var(--space-4);
  bottom: 88px;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--brand-blue);
  color: white;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-fast);
  z-index: 90;
}

.fab:hover {
  transform: scale(1.05);
  box-shadow: 0 6px 20px rgba(35, 131, 226, 0.3);
}

/* ===== 底部导航 - 移动端 ===== */
.mobile-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 64px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-default);
  z-index: 100;
  padding-bottom: env(safe-area-inset-bottom);
}

.mobile-nav-items {
  display: flex;
  height: 64px;
}

.mobile-nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: var(--font-xs);
  cursor: pointer;
  border: none;
  background: none;
  transition: color var(--transition-fast);
}

.mobile-nav-item.active {
  color: var(--brand-blue);
}

.mobile-nav-item .icon {
  width: 24px;
  height: 24px;
}

/* ===== 响应式断点 ===== */

/* 平板 < 1024px */
@media (max-width: 1024px) {
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .progress-grid {
    grid-template-columns: 1fr;
  }
  
  .habits-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* 手机 < 640px */
@media (max-width: 640px) {
  .sidebar {
    transform: translateX(-100%);
  }
  
  .main-content {
    margin-left: 0;
    padding: var(--space-4) var(--space-4) 100px;
  }
  
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-3);
  }
  
  .stat-value {
    font-size: var(--font-2xl);
  }
  
  .habits-grid {
    grid-template-columns: 1fr;
  }
  
  .mobile-nav {
    display: block;
  }
  
  .task-actions {
    opacity: 1;
  }
}

/* 超小屏幕 < 400px */
@media (max-width: 400px) {
  .stats-grid {
    grid-template-columns: 1fr;
  }
}

/* ===== 工具类 ===== */
.flex { display: flex; }
.flex-col { display: flex; flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }

.mb-2 { margin-bottom: var(--space-2); }
.mb-3 { margin-bottom: var(--space-3); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mt-2 { margin-top: var(--space-2); }
.mt-6 { margin-top: var(--space-6); }

.text-sm { font-size: var(--font-sm); }
.text-xs { font-size: var(--font-xs); }
.text-secondary { color: var(--text-secondary); }

.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }

/* ===== 仪表盘双栏布局 ===== */
.dashboard-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
}

/* ===== 空状态 ===== */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-8) var(--space-4);
  color: var(--text-tertiary);
  text-align: center;
}

.empty-state .icon {
  color: var(--text-tertiary);
  margin-bottom: var(--space-2);
}

.empty-state p {
  font-size: var(--font-sm);
  color: var(--text-secondary);
}

/* ===== 表单 ===== */
.form-group {
  margin-bottom: var(--space-4);
}

.form-label {
  display: block;
  font-size: var(--font-xs);
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: var(--space-1);
}

.form-input, .form-select, .form-textarea {
  width: 100%;
  padding: var(--space-2) var(--space-3);
  font-size: var(--font-sm);
  font-family: inherit;
  color: var(--text-primary);
  background: var(--bg-secondary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus, .form-select:focus, .form-textarea:focus {
  border-color: var(--brand-blue);
  box-shadow: 0 0 0 3px rgba(35, 131, 226, 0.15);
}

.form-input::placeholder {
  color: var(--text-tertiary);
}

textarea.form-input {
  resize: vertical;
  min-height: 40px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3);
}

/* ===== 弹窗 ===== */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.35);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
  padding: var(--space-4);
}

.modal {
  background: var(--bg-secondary);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
}

.modal-sm {
  max-width: 400px;
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--space-6);
  border-bottom: 1px solid var(--border-default);
  position: sticky;
  top: 0;
  background: var(--bg-secondary);
  z-index: 1;
}

.modal-title {
  font-size: var(--font-lg);
  font-weight: 600;
  color: var(--text-primary);
}

.modal-body {
  padding: var(--space-6);
}

.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: var(--space-2);
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--border-default);
}

/* ===== Toast 提示 ===== */
.toast-container {
  position: fixed;
  top: var(--space-6);
  left: 50%;
  transform: translateX(-50%);
  z-index: 400;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
  pointer-events: none;
}

.toast {
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--font-sm);
  font-weight: 500;
  box-shadow: var(--shadow-md);
  white-space: nowrap;
}

.toast-success {
  background: var(--brand-green);
  color: white;
}

.toast-error {
  background: var(--brand-red);
  color: white;
}

.toast-info {
  background: var(--text-primary);
  color: white;
}

/* ===== 知识库布局 ===== */
.knowledge-layout {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: var(--space-4);
  align-items: start;
}

.knowledge-sidebar {
  position: sticky;
  top: var(--space-4);
}

.tree-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.tree-item {
  border-bottom: 1px solid var(--border-default);
  padding-bottom: var(--space-2);
}

.tree-dir {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-1) 0;
  font-size: var(--font-sm);
  font-weight: 600;
  color: var(--text-primary);
}

.tree-dir .icon {
  color: var(--brand-orange);
}

.tree-files {
  display: flex;
  flex-direction: column;
  margin-left: var(--space-6);
  gap: 2px;
}

.tree-file {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-1) var(--space-2);
  font-size: var(--font-sm);
  color: var(--text-secondary);
  border: none;
  background: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  text-align: left;
  width: 100%;
  transition: all var(--transition-fast);
}

.tree-file:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.tree-file .icon {
  color: var(--text-tertiary);
}

.markdown-body {
  min-height: 300px;
}

/* ===== 热力图 ===== */
.calendar-heatmap {
  display: flex;
  flex-direction: column;
  gap: 3px;
  align-items: flex-start;
}

.calendar-week {
  display: flex;
  gap: 3px;
}

.calendar-day {
  width: 14px;
  height: 14px;
  border-radius: 3px;
  background: var(--bg-active);
}

.calendar-day.level-1 { background: rgba(15, 123, 108, 0.2); }
.calendar-day.level-2 { background: rgba(15, 123, 108, 0.4); }
.calendar-day.level-3 { background: rgba(15, 123, 108, 0.6); }
.calendar-day.level-4 { background: rgba(15, 123, 108, 0.85); }
.calendar-day.today { outline: 2px solid var(--brand-orange); outline-offset: 1px; }

/* ===== 响应式补充 ===== */
@media (max-width: 1024px) {
  .dashboard-grid {
    grid-template-columns: 1fr;
  }
  .knowledge-layout {
    grid-template-columns: 1fr;
  }
  .knowledge-sidebar {
    position: static;
    max-height: 300px;
    overflow-y: auto;
  }
}

@media (max-width: 640px) {
  .form-row {
    grid-template-columns: 1fr;
  }
  .modal {
    max-height: 85vh;
    margin: 0;
  }
}

/* ========== 新日历热力图样式（大尺寸 + 环形进度 + 日期标注） ========== */

/* 星期标题 */
.calendar-week-header {
  display: flex;
  gap: 4px;
  margin-bottom: 6px;
  padding-left: 0;
}

.calendar-week-header span {
  flex: 1;
  text-align: center;
  font-size: 11px;
  font-weight: 500;
  color: var(--text-secondary);
}

/* 日历行 */
.calendar-week {
  display: flex;
  gap: 4px;
  margin-bottom: 4px;
}

/* 日历格子（36px × 36px，圆角 6px） */
.calendar-day {
  flex: 1;
  min-width: 36px;
  height: 36px;
  border-radius: 6px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 500;
  position: relative;
  transition: transform 0.15s, box-shadow 0.15s;
}

.calendar-day.empty {
  background: transparent;
}

.calendar-day.level-0 {
  background: #f3f4f6;
  color: #9ca3af;
}

.calendar-day.level-1 {
  background: rgba(15, 123, 108, 0.15);
  color: #0f7b6c;
}

.calendar-day.level-2 {
  background: rgba(15, 123, 108, 0.35);
  color: #0f7b6c;
}

.calendar-day.level-3 {
  background: rgba(15, 123, 108, 0.6);
  color: white;
}

.calendar-day.level-4 {
  background: #0f7b6c;
  color: white;
}

/* 今日高亮 */
.calendar-day.today {
  outline: 2px solid #f59e0b;
  outline-offset: 1px;
  box-shadow: 0 1px 4px rgba(245, 158, 11, 0.3);
}

/* 环形进度（SVG 环形进度条） */
.calendar-ring {
  position: absolute;
  bottom: 3px;
  width: 10px;
  height: 10px;
  transform: rotate(-90deg);
}

.calendar-ring circle {
  fill: none;
  stroke-width: 2;
}

.calendar-ring .bg {
  stroke: rgba(0, 0, 0, 0.1);
}

.calendar-ring .fg {
  stroke: #0f7b6c;
  stroke-linecap: round;
}

.calendar-day.level-0 .calendar-ring {
  display: none;
}

/* 悬停效果 */
.calendar-day:not(.empty):hover {
  transform: translateY(-1px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.12);
  cursor: pointer;
}

/* 悬停提示 */
.calendar-tooltip {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  margin-bottom: 8px;
  padding: 8px 12px;
  background: var(--text-primary);
  color: white;
  font-size: 12px;
  border-radius: 6px;
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.15s, visibility 0.15s;
  z-index: 100;
}

.calendar-day:hover .calendar-tooltip {
  opacity: 1;
  visibility: visible;
}
    padding: var(--space-4);
  }
}