@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

:root {
  --primary: #2563EB;
  --primary-dark: #1D4ED8;
  --primary-light: #3B82F6;
  --bg: #F8FAFC;
  --surface: #FFFFFF;
  --text: #1E293B;
  --text-secondary: #64748B;
  --border: #E2E8F0;
  --success: #22C55E;
  --danger: #EF4444;
  --warning: #F59E0B;
  --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -1px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
  --radius: 12px;
  --radius-sm: 8px;
}

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

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

/* ========== 导航栏 ========== */
.navbar {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
  background: rgba(255,255,255,0.95);
}

.navbar-brand {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
}

.nav-link:hover {
  color: var(--primary);
  background: rgba(37, 99, 235, 0.08);
}

/* ========== 容器 ========== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 32px 24px;
}

/* ========== 卡片 ========== */
.card {
  background: var(--surface);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: box-shadow 0.2s;
}

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

.card-header {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.card-body { padding: 24px; }

/* ========== 按钮 ========== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  border: none;
  transition: all 0.2s;
  text-decoration: none;
}

.btn-primary {
  background: var(--primary);
  color: white;
}
.btn-primary:hover { background: var(--primary-dark); }

.btn-secondary {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
}
.btn-secondary:hover { background: var(--border); }

.btn-danger {
  background: var(--danger);
  color: white;
}
.btn-danger:hover { background: #DC2626; }

.btn-success {
  background: var(--success);
  color: white;
}

.btn-sm { padding: 4px 10px; font-size: 12px; }

/* ========== 表单 ========== */
.form-group { margin-bottom: 16px; }

.form-label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  margin-bottom: 6px;
}

.form-input, .form-select, .form-textarea {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-family: inherit;
  transition: border-color 0.2s, box-shadow 0.2s;
  background: var(--surface);
  color: var(--text);
}

.form-input:focus, .form-select:focus, .form-textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.form-textarea { resize: vertical; min-height: 80px; }

/* ========== 表格 ========== */
.table-wrapper { overflow-x: auto; }

.table {
  width: 100%;
  border-collapse: collapse;
}

.table th, .table td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}

.table th {
  background: var(--bg);
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.table tr:hover td { background: var(--bg); }

.table .actions { display: flex; gap: 8px; }

/* ========== 分类树 ========== */
.category-tree { list-style: none; }

.category-item {
  margin-bottom: 4px;
}

.category-link {
  display: flex;
  align-items: center;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  color: var(--text);
  text-decoration: none;
  font-size: 14px;
  transition: all 0.15s;
  gap: 8px;
}

.category-link:hover {
  background: rgba(37, 99, 235, 0.08);
  color: var(--primary);
}

.category-icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 14px;
  flex-shrink: 0;
}

.category-link .name { flex: 1; font-weight: 500; }

.category-link .count {
  font-size: 12px;
  color: var(--text-secondary);
  background: var(--bg);
  padding: 2px 8px;
  border-radius: 10px;
}

.category-children {
  list-style: none;
  margin-left: 44px;
  margin-top: 4px;
  border-left: 1px dashed var(--border);
  padding-left: 12px;
}

/* ========== 页面卡片 ========== */
.page-card {
  display: block;
  padding: 20px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--surface);
  text-decoration: none;
  color: var(--text);
  transition: all 0.2s;
  margin-bottom: 12px;
}

.page-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

.page-card-title {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text);
}

.page-card-desc {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 10px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.page-card-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  color: var(--text-secondary);
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: 10px;
  font-size: 11px;
  font-weight: 600;
}

.badge-protected {
  background: rgba(245, 158, 11, 0.15);
  color: var(--warning);
}

.badge-public {
  background: rgba(34, 197, 94, 0.15);
  color: var(--success);
}

/* ========== 模态框 ========== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  backdrop-filter: blur(2px);
  animation: fadeIn 0.2s;
}

.modal {
  background: var(--surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  width: 90%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  animation: slideUp 0.2s;
}

.modal-header {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title { font-size: 16px; font-weight: 600; }

.modal-close {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: none;
  background: var(--bg);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: var(--text-secondary);
  transition: all 0.15s;
}

.modal-close:hover { background: var(--border); color: var(--text); }

.modal-body { padding: 24px; }
.modal-footer { padding: 16px 24px; border-top: 1px solid var(--border); display: flex; justify-content: flex-end; gap: 8px; }

/* ========== Toast ========== */
.toast-container {
  position: fixed;
  top: 80px;
  right: 24px;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toast {
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 500;
  box-shadow: var(--shadow-lg);
  animation: slideIn 0.3s;
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 240px;
}

.toast-success { background: var(--success); color: white; }
.toast-error { background: var(--danger); color: white; }

/* ========== 兑换码输入 ========== */
.code-overlay {
  position: fixed;
  inset: 0;
  background: linear-gradient(135deg, rgba(37,99,235,0.95), rgba(29,78,216,0.95));
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 500;
  backdrop-filter: blur(8px);
}

.code-box {
  background: white;
  border-radius: 20px;
  padding: 40px;
  text-align: center;
  max-width: 400px;
  width: 90%;
  box-shadow: 0 25px 50px -12px rgba(0,0,0,0.25);
  animation: slideUp 0.3s;
}

.code-box h2 {
  font-size: 22px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}

.code-box p {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.code-input {
  width: 100%;
  padding: 14px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 18px;
  text-align: center;
  letter-spacing: 0.2em;
  font-weight: 600;
  text-transform: uppercase;
  transition: border-color 0.2s;
}

.code-input:focus {
  outline: none;
  border-color: var(--primary);
}

.code-btn {
  width: 100%;
  margin-top: 12px;
  padding: 14px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

.code-btn:hover { background: var(--primary-dark); }

.code-error {
  color: var(--danger);
  font-size: 13px;
  margin-top: 10px;
  display: none;
}

.lock-icon {
  width: 64px;
  height: 64px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  font-size: 28px;
  color: white;
}

/* ========== 内容阅读区 ========== */
.content-reader {
  max-width: 800px;
  margin: 0 auto;
  padding: 40px 24px;
}

.content-header {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border);
}

.content-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}

.content-meta {
  font-size: 13px;
  color: var(--text-secondary);
  display: flex;
  gap: 16px;
  align-items: center;
}

.content-body {
  font-size: 16px;
  line-height: 1.8;
  color: var(--text);
}

.content-body img { max-width: 100%; height: auto; border-radius: var(--radius-sm); }
.content-body a { color: var(--primary); }

/* ========== 登录页 ========== */
.login-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  padding: 24px;
}

.login-card {
  background: white;
  border-radius: 20px;
  padding: 48px 40px;
  width: 100%;
  max-width: 400px;
  box-shadow: 0 25px 50px -12px rgba(0,0,0,0.25);
}

.login-logo {
  text-align: center;
  margin-bottom: 32px;
}

.login-logo h1 {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 4px;
}

.login-logo p {
  font-size: 13px;
  color: var(--text-secondary);
}

/* ========== 动画 ========== */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

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

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

/* ========== 响应式 ========== */
@media (max-width: 768px) {
  .container { padding: 20px 16px; }
  .card-body { padding: 16px; }
  .table th, .table td { padding: 10px 12px; }
  .content-title { font-size: 22px; }
  .login-card { padding: 32px 24px; }
}

/* ========== 空状态 ========== */
.empty-state {
  text-align: center;
  padding: 60px 24px;
  color: var(--text-secondary);
}

.empty-icon {
  font-size: 48px;
  margin-bottom: 16px;
  opacity: 0.5;
}

.empty-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
}

/* ========== 网格布局 ========== */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }

@media (max-width: 768px) {
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
}

/* ========== 标签页 ========== */
.tabs {
  display: flex;
  gap: 4px;
  border-bottom: 2px solid var(--border);
  margin-bottom: 24px;
}

.tab {
  padding: 10px 20px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: all 0.15s;
}

.tab:hover { color: var(--primary); }

.tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}