/* ============================================
   AI 去水印 — 共享样式表
   ============================================ */

/* ----- 1. CSS Reset ----- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Noto Sans SC", "Source Han Sans SC", "WenQuanYi Micro Hei",
    sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-page);
  transition: background-color 0.3s, color 0.3s;
  min-height: 100vh;
}

img, svg, video, canvas {
  display: block;
  max-width: 100%;
}

a {
  color: var(--color-primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

ul, ol {
  list-style: none;
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
  border: none;
  outline: none;
  background: none;
}

button {
  cursor: pointer;
}

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

h1, h2, h3, h4, h5, h6 {
  line-height: 1.3;
  font-weight: 600;
}

/* ----- 2. Color Variables (Light / Dark) ----- */
:root {
  /* Primary palette — 淡蓝色 */
  --color-primary: #38BDF8;
  --color-primary-hover: #0EA5E9;
  --color-primary-active: #0284C7;
  --color-primary-light: #E0F2FE;
  --color-primary-bg: rgba(56, 189, 248, 0.08);

  /* Semantic */
  --color-success: #059669;
  --color-success-light: #D1FAE5;
  --color-warning: #D97706;
  --color-warning-light: #FEF3C7;
  --color-danger: #DC2626;
  --color-danger-light: #FEE2E2;
  --color-info: #2563EB;
  --color-info-light: #DBEAFE;

  /* Aliases (used by page-level inline CSS) */
  --color-surface: var(--bg-card);
  --color-surface-alt: var(--bg-hover);
  --color-surface-hover: var(--bg-hover);
  --color-border: var(--border-color);
  --color-text: var(--text-primary);
  --color-text-secondary: var(--text-secondary);
  --color-text-muted: var(--text-tertiary);
  --primary: var(--color-primary);
  --primary-hover: var(--color-primary-hover);
  --primary-light: var(--color-primary-bg);
  --border: var(--border-color);
  --bg-main: var(--bg-page);
  --shadow: var(--shadow-sm);

  /* Light mode surfaces — white elegant */
  --bg-page: #FFFFFF;
  --bg-card: #FFFFFF;
  --bg-input: #FFFFFF;
  --bg-hover: #F3F4F6;
  --bg-code: #F3F4F6;

  /* Light mode text */
  --text-primary: #111827;
  --text-secondary: #6B7280;
  --text-tertiary: #9CA3AF;
  --text-inverse: #FFFFFF;

  /* Borders */
  --border-color: #E5E7EB;
  --border-color-strong: #D1D5DB;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.06);

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  /* Spacing scale */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-10: 40px;
  --space-12: 48px;
  --space-16: 64px;

  /* Sidebar (admin) */
  --sidebar-width: 260px;
  --sidebar-bg: #1F2937;
  --sidebar-text: #D1D5DB;
  --sidebar-text-active: #FFFFFF;
  --sidebar-item-hover: rgba(255,255,255,0.06);
  --sidebar-item-active: rgba(56,189,248,0.25);

  /* Transition */
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s ease;
  --transition-slow: 0.35s ease;

  /* Z-index layers */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-modal-backdrop: 300;
  --z-modal: 400;
  --z-toast: 500;
  --z-tooltip: 600;
}

/* Dark mode via media query */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg-main: var(--bg-page);
    --border: var(--border-color);
    --primary: var(--color-primary);
    --primary-hover: var(--color-primary-hover);
    --shadow: var(--shadow-sm);
    --bg-page: #111827;
    --bg-card: #1F2937;
    --bg-input: #374151;
    --bg-hover: #374151;
    --bg-code: #374151;
    --text-primary: #F9FAFB;
    --text-secondary: #D1D5DB;
    --text-tertiary: #9CA3AF;
    --border-color: #374151;
    --border-color-strong: #4B5563;
    --color-primary-light: rgba(56,189,248,0.18);
    --color-primary-bg: rgba(56,189,248,0.15);
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.35), 0 2px 4px -2px rgba(0,0,0,0.25);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.4), 0 4px 6px -4px rgba(0,0,0,0.3);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.5), 0 8px 10px -6px rgba(0,0,0,0.4);
  }
}

/* Dark mode via data-theme attribute (toggle wins) */
:root[data-theme="dark"] {
  --bg-main: var(--bg-page);
  --border: var(--border-color);
  --primary: var(--color-primary);
  --primary-hover: var(--color-primary-hover);
  --shadow: var(--shadow-sm);
  --bg-page: #111827;
  --bg-card: #1F2937;
  --bg-input: #374151;
  --bg-hover: #374151;
  --bg-code: #374151;
  --text-primary: #F9FAFB;
  --text-secondary: #D1D5DB;
  --text-tertiary: #9CA3AF;
  --border-color: #374151;
  --border-color-strong: #4B5563;
  --color-primary-light: rgba(56,189,248,0.18);
  --color-primary-bg: rgba(56,189,248,0.15);
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.35), 0 2px 4px -2px rgba(0,0,0,0.25);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.4), 0 4px 6px -4px rgba(0,0,0,0.3);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.5), 0 8px 10px -6px rgba(0,0,0,0.4);
}

/* Force light via data-theme */
:root[data-theme="light"] {
  --bg-page: #F9FAFB;
  --bg-card: #FFFFFF;
  --bg-input: #FFFFFF;
  --bg-hover: #F3F4F6;
  --bg-code: #F3F4F6;
  --text-primary: #111827;
  --text-secondary: #6B7280;
  --text-tertiary: #9CA3AF;
  --border-color: #E5E7EB;
  --border-color-strong: #D1D5DB;
  --color-primary-light: #EEF2FF;
  --color-primary-bg: rgba(56,189,248,0.08);
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.06);
}

/* ----- 3. Layout Utilities ----- */
.container {
  width: 100%;
  max-width: 960px;
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.container-lg {
  max-width: 1200px;
}

.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.flex-wrap {
  flex-wrap: wrap;
}

.items-center {
  align-items: center;
}

.items-start {
  align-items: flex-start;
}

.justify-center {
  justify-content: center;
}

.justify-between {
  justify-content: space-between;
}

.justify-end {
  justify-content: flex-end;
}

.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

.grid {
  display: grid;
}

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

.flex-1 {
  flex: 1;
}

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

.text-right {
  text-align: right;
}

.w-full {
  width: 100%;
}

.hidden {
  display: none !important;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

/* ----- 4. Buttons ----- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 10px 20px;
  font-size: 0.9375rem;
  font-weight: 500;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  white-space: nowrap;
  user-select: none;
  line-height: 1.4;
}

.btn:hover {
  text-decoration: none;
}

.btn:disabled, .btn.is-loading {
  opacity: 0.55;
  cursor: not-allowed;
  pointer-events: none;
}

.btn-primary {
  background: var(--color-primary);
  color: #FFFFFF;
}

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

.btn-primary:active {
  background: var(--color-primary-active);
}

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

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

.btn-danger {
  background: var(--color-danger);
  color: #FFFFFF;
}

.btn-danger:hover {
  background: #B91C1C;
}

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

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

.btn-sm {
  padding: 6px 12px;
  font-size: 0.8125rem;
}

.btn-lg {
  padding: 14px 28px;
  font-size: 1.0625rem;
}

.btn-icon {
  padding: 8px;
  border-radius: var(--radius-md);
}

.btn-icon.btn-sm {
  padding: 6px;
}

/* ----- 5. Form Inputs ----- */
.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.form-label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-primary);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: 10px 14px;
  font-size: 0.9375rem;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-bg);
}

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

.form-textarea {
  resize: vertical;
  min-height: 120px;
}

.form-select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%236B7280' viewBox='0 0 16 16'%3E%3Cpath d='M8 11.4L2.6 6h10.8L8 11.4z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}

.form-hint {
  font-size: 0.8125rem;
  color: var(--text-tertiary);
}

.form-error {
  font-size: 0.8125rem;
  color: var(--color-danger);
}

.form-input.is-error,
.form-textarea.is-error {
  border-color: var(--color-danger);
}

.form-input.is-error:focus,
.form-textarea.is-error:focus {
  box-shadow: 0 0 0 3px rgba(220,38,38,0.12);
}

/* ----- 6. Card ----- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

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

.card-header {
  padding: var(--space-4) var(--space-6);
  border-bottom: 1px solid var(--border-color);
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-footer {
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--border-color);
  background: var(--bg-hover);
}

/* Stat card variant */
.stat-card {
  padding: var(--space-5);
}

.stat-card .stat-label {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-1);
}

.stat-card .stat-value {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.2;
}

.stat-card .stat-change {
  font-size: 0.8125rem;
  margin-top: var(--space-1);
}

.stat-card .stat-change.up {
  color: var(--color-success);
}

.stat-card .stat-change.down {
  color: var(--color-danger);
}

/* ----- 7. Modal / Dialog ----- */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: var(--z-modal-backdrop);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-base), visibility var(--transition-base);
}

.modal-backdrop.is-active {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
  z-index: var(--z-modal);
  transform: translateY(20px) scale(0.97);
  transition: transform var(--transition-base);
}

.modal-backdrop.is-active .modal {
  transform: translateY(0) scale(1);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-5) var(--space-6);
  border-bottom: 1px solid var(--border-color);
}

.modal-header h3 {
  font-size: 1.125rem;
  font-weight: 600;
}

.modal-close {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  transition: background var(--transition-fast);
  font-size: 1.25rem;
}

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

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

.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--border-color);
}

/* ----- 8. Table ----- */
.table-wrapper {
  overflow-x: auto;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
}

.table {
  width: 100%;
  font-size: 0.875rem;
}

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

.table th {
  padding: 12px 16px;
  text-align: left;
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 0.8125rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  white-space: nowrap;
  border-bottom: 1px solid var(--border-color);
}

.table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-primary);
}

.table tbody tr:last-child td {
  border-bottom: none;
}

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

.table td.mono {
  font-family: "SF Mono", "Fira Code", "Consolas", monospace;
  font-size: 0.8125rem;
}

/* ----- 9. Badge / Tag ----- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 10px;
  font-size: 0.75rem;
  font-weight: 500;
  border-radius: var(--radius-full);
  line-height: 1.6;
}

.badge-primary {
  background: var(--color-primary-light);
  color: var(--color-primary);
}

.badge-success {
  background: var(--color-success-light);
  color: var(--color-success);
}

.badge-warning {
  background: var(--color-warning-light);
  color: var(--color-warning);
}

.badge-danger {
  background: var(--color-danger-light);
  color: var(--color-danger);
}

.badge-info {
  background: var(--color-info-light);
  color: var(--color-info);
}

.badge-neutral {
  background: var(--bg-hover);
  color: var(--text-secondary);
}

/* Dot indicator inside badge */
.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  margin-right: 6px;
  flex-shrink: 0;
}

.badge-success .badge-dot { background: var(--color-success); }
.badge-danger .badge-dot  { background: var(--color-danger); }
.badge-warning .badge-dot { background: var(--color-warning); }

/* ----- 10. Loading Spinner ----- */
.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2.5px solid var(--border-color);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

.spinner-sm {
  width: 14px;
  height: 14px;
  border-width: 2px;
}

.spinner-lg {
  width: 36px;
  height: 36px;
  border-width: 3.5px;
}

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

/* Loading overlay */
.loading-overlay {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-4);
  padding: var(--space-12) var(--space-4);
  color: var(--text-secondary);
  font-size: 0.9375rem;
}

/* Skeleton placeholder */
.skeleton {
  background: linear-gradient(90deg, var(--bg-hover) 25%, var(--border-color) 50%, var(--bg-hover) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: var(--radius-sm);
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ----- 11. Progress Bar ----- */
.progress {
  width: 100%;
  height: 8px;
  background: var(--bg-hover);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  background: var(--color-primary);
  border-radius: var(--radius-full);
  transition: width var(--transition-base);
  min-width: 0;
}

.progress-bar.is-success {
  background: var(--color-success);
}

.progress-bar.is-danger {
  background: var(--color-danger);
}

.progress-sm {
  height: 4px;
}

.progress-lg {
  height: 12px;
}

/* ----- 12. Toast / Notification ----- */
.toast-container {
  position: fixed;
  top: var(--space-4);
  right: var(--space-4);
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  pointer-events: none;
  max-width: 420px;
  width: calc(100% - 32px);
}

.toast {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  pointer-events: auto;
  animation: slideInRight 0.3s ease;
  transition: opacity 0.3s, transform 0.3s;
}

.toast.is-removing {
  opacity: 0;
  transform: translateX(100%);
}

.toast-icon {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  margin-top: 1px;
}

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

.toast-title {
  font-weight: 600;
  font-size: 0.875rem;
  margin-bottom: 2px;
}

.toast-message {
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

.toast-close {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-tertiary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition-fast);
}

.toast-close:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.toast.toast-success { border-left: 3px solid var(--color-success); }
.toast.toast-danger  { border-left: 3px solid var(--color-danger); }
.toast.toast-warning { border-left: 3px solid var(--color-warning); }
.toast.toast-info    { border-left: 3px solid var(--color-info); }

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(80px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* ----- 13. Tabs ----- */
.tabs {
  display: flex;
  gap: var(--space-1);
  border-bottom: 2px solid var(--border-color);
  padding: 0;
}

.tab-item {
  padding: 10px 20px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: color var(--transition-fast), border-color var(--transition-fast);
  cursor: pointer;
  user-select: none;
  background: none;
  border-top: none;
  border-left: none;
  border-right: none;
}

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

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

.tab-panel {
  display: none;
  padding-top: var(--space-6);
}

.tab-panel.is-active {
  display: block;
}

/* Pill-style tabs variant */
.tabs-pill {
  border-bottom: none;
  background: var(--bg-hover);
  border-radius: var(--radius-md);
  padding: 3px;
  gap: 0;
}

.tabs-pill .tab-item {
  border-bottom: none;
  margin-bottom: 0;
  border-radius: var(--radius-sm);
  padding: 8px 18px;
}

.tabs-pill .tab-item.is-active {
  background: var(--bg-card);
  box-shadow: var(--shadow-sm);
  color: var(--text-primary);
}

/* ----- 14. Navigation ----- */

/* Top nav (main page) */
.top-nav {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border-color);
  padding: 0 var(--space-4);
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
}

.top-nav .nav-inner {
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.top-nav .nav-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
}

.top-nav .nav-brand .brand-icon {
  width: 32px;
  height: 32px;
  background: var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFFFFF;
  font-size: 1rem;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* Sidebar nav (admin page) */
.admin-layout {
  display: flex;
  min-height: 100vh;
}

.sidebar {
  width: var(--sidebar-width);
  background: var(--sidebar-bg);
  color: var(--sidebar-text);
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: var(--z-sticky);
  transition: transform var(--transition-base);
}

.sidebar-header {
  padding: var(--space-5) var(--space-5);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.sidebar-header .brand-icon {
  width: 36px;
  height: 36px;
  background: var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFF;
  font-size: 1.125rem;
  flex-shrink: 0;
}

.sidebar-header .brand-text {
  font-size: 1rem;
  font-weight: 700;
  color: #FFFFFF;
}

.sidebar-header .brand-sub {
  font-size: 0.75rem;
  color: var(--sidebar-text);
}

.sidebar-nav {
  flex: 1;
  padding: var(--space-4) var(--space-3);
  overflow-y: auto;
}

.sidebar-section-title {
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: rgba(255,255,255,0.35);
  padding: var(--space-4) var(--space-3) var(--space-2);
}

.sidebar-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 10px var(--space-3);
  border-radius: var(--radius-md);
  color: var(--sidebar-text);
  font-size: 0.9375rem;
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast);
  text-decoration: none;
  user-select: none;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
}

.sidebar-item:hover {
  background: var(--sidebar-item-hover);
  color: #FFFFFF;
  text-decoration: none;
}

.sidebar-item.is-active {
  background: var(--sidebar-item-active);
  color: var(--sidebar-text-active);
}

.sidebar-item .item-icon {
  width: 20px;
  text-align: center;
  flex-shrink: 0;
  font-size: 1rem;
}

.sidebar-footer {
  padding: var(--space-4) var(--space-3);
  border-top: 1px solid rgba(255,255,255,0.08);
}

/* Admin main content */
.admin-main {
  flex: 1;
  margin-left: var(--sidebar-width);
  min-height: 100vh;
}

.admin-topbar {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border-color);
  padding: 0 var(--space-6);
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
}

.admin-topbar h1 {
  font-size: 1.125rem;
  font-weight: 600;
}

.admin-content {
  padding: var(--space-6);
}

/* Mobile sidebar toggle */
.sidebar-toggle {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 1.25rem;
}

/* ----- 15. Drag & Drop Upload Zone ----- */
.upload-zone {
  border: 2px dashed var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--space-10) var(--space-6);
  text-align: center;
  cursor: pointer;
  transition: border-color var(--transition-fast), background var(--transition-fast);
  position: relative;
}

.upload-zone:hover {
  border-color: var(--color-primary);
  background: var(--color-primary-bg);
}

.upload-zone.is-dragover {
  border-color: var(--color-primary);
  background: var(--color-primary-bg);
  border-style: solid;
}

.upload-zone.has-file {
  border-color: var(--color-success);
  border-style: solid;
  background: rgba(5,150,105,0.04);
}

.upload-zone input[type="file"] {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}

.upload-zone .upload-icon {
  font-size: 2.5rem;
  margin-bottom: var(--space-4);
  color: var(--text-tertiary);
}

.upload-zone.is-dragover .upload-icon,
.upload-zone:hover .upload-icon {
  color: var(--color-primary);
}

.upload-zone .upload-title {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.upload-zone .upload-hint {
  font-size: 0.8125rem;
  color: var(--text-tertiary);
}

.upload-zone .upload-formats {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-2);
  margin-top: var(--space-4);
}

.upload-zone .format-tag {
  padding: 2px 10px;
  background: var(--bg-hover);
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* ----- 16. Responsive ----- */
@media (max-width: 1024px) {
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

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

  .grid-4 {
    grid-template-columns: 1fr;
  }

  /* Admin sidebar */
  .sidebar {
    transform: translateX(-100%);
  }

  .sidebar.is-open {
    transform: translateX(0);
  }

  .admin-main {
    margin-left: 0;
  }

  .sidebar-toggle {
    display: flex;
  }

  /* Mobile sidebar overlay */
  .sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.4);
    z-index: calc(var(--z-sticky) - 1);
  }

  .sidebar-overlay.is-active {
    display: block;
  }

  .admin-content {
    padding: var(--space-4);
  }
}

@media (max-width: 640px) {
  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }

  .container {
    padding: 0 var(--space-3);
  }

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

  .modal {
    max-width: 100%;
    margin: var(--space-4);
    max-height: calc(100vh - 32px);
  }

  .tabs {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .tab-item {
    padding: 8px 14px;
    font-size: 0.875rem;
    flex-shrink: 0;
  }

  .btn {
    padding: 8px 16px;
    font-size: 0.875rem;
  }

  .btn-lg {
    padding: 12px 22px;
    font-size: 1rem;
  }

  .top-nav .nav-inner {
    height: 52px;
  }

  .upload-zone {
    padding: var(--space-8) var(--space-4);
  }
}

/* ----- 17. Transitions & Animations ----- */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.95);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.anim-fade-in     { animation: fadeIn 0.3s ease; }
.anim-fade-in-up  { animation: fadeInUp 0.35s ease; }
.anim-fade-in-down { animation: fadeInDown 0.35s ease; }
.anim-scale-in    { animation: scaleIn 0.25s ease; }

/* ----- 18. Tooltip ----- */
.tooltip-wrapper {
  position: relative;
  display: inline-flex;
}

.tooltip {
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  padding: 6px 12px;
  background: var(--sidebar-bg);
  color: #FFFFFF;
  font-size: 0.75rem;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  pointer-events: none;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-fast), visibility var(--transition-fast);
  z-index: var(--z-tooltip);
}

.tooltip::after {
  content: "";
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 5px solid transparent;
  border-top-color: var(--sidebar-bg);
}

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

/* ----- 19. Pagination ----- */
.pagination {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.page-item {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  height: 36px;
  padding: 0 8px;
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast);
  background: none;
  border: none;
  user-select: none;
}

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

.page-item.is-active {
  background: var(--color-primary);
  color: #FFFFFF;
}

.page-item:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  pointer-events: none;
}

.page-info {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  margin: 0 var(--space-2);
}

/* ----- 20. Toggle Switch ----- */
.toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  cursor: pointer;
  gap: var(--space-2);
  user-select: none;
}

.toggle input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-track {
  width: 44px;
  height: 24px;
  background: var(--border-color-strong);
  border-radius: var(--radius-full);
  position: relative;
  transition: background var(--transition-fast);
  flex-shrink: 0;
}

.toggle-track::after {
  content: "";
  position: absolute;
  top: 3px;
  left: 3px;
  width: 18px;
  height: 18px;
  background: #FFFFFF;
  border-radius: 50%;
  transition: transform var(--transition-fast);
  box-shadow: 0 1px 3px rgba(0,0,0,0.15);
}

.toggle input:checked + .toggle-track {
  background: var(--color-primary);
}

.toggle input:checked + .toggle-track::after {
  transform: translateX(20px);
}

.toggle-label {
  font-size: 0.875rem;
  color: var(--text-primary);
}

/* ----- Additional Components ----- */

/* Theme toggle button */
.theme-toggle {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast);
  background: none;
  border: none;
  font-size: 1.125rem;
}

.theme-toggle:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

/* Result section */
.result-section {
  margin-top: var(--space-6);
  animation: fadeInUp 0.35s ease;
}

.result-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-4);
}

.result-header h3 {
  font-size: 1rem;
  font-weight: 600;
}

/* Cleaned text output */
.text-output {
  position: relative;
  background: var(--bg-code);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  font-size: 0.9375rem;
  line-height: 1.7;
  white-space: pre-wrap;
  word-break: break-word;
  min-height: 80px;
  max-height: 400px;
  overflow-y: auto;
}

.copy-btn {
  position: absolute;
  top: var(--space-2);
  right: var(--space-2);
}

/* Watermark type list */
.watermark-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.watermark-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-3) var(--space-4);
  background: var(--bg-hover);
  border-radius: var(--radius-md);
}

.watermark-item .wm-type {
  font-weight: 500;
  font-size: 0.875rem;
}

.watermark-item .wm-desc {
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

.watermark-item .wm-count {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-primary);
}

/* JSON viewer */
.json-viewer {
  background: #1E1E2E;
  color: #CDD6F4;
  border-radius: var(--radius-md);
  padding: var(--space-4);
  font-family: "SF Mono", "Fira Code", "Consolas", monospace;
  font-size: 0.8125rem;
  line-height: 1.6;
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-all;
  max-height: 500px;
  overflow-y: auto;
}

/* File info display */
.file-info {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  background: var(--bg-hover);
  border-radius: var(--radius-md);
}

.file-info .file-icon {
  font-size: 1.5rem;
}

.file-info .file-name {
  font-weight: 500;
  font-size: 0.875rem;
}

.file-info .file-size {
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

/* Empty state */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-12) var(--space-6);
  text-align: center;
  color: var(--text-tertiary);
}

.empty-state .empty-icon {
  font-size: 3rem;
  margin-bottom: var(--space-4);
}

.empty-state .empty-title {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: var(--space-2);
}

.empty-state .empty-desc {
  font-size: 0.875rem;
  max-width: 360px;
}

/* Footer */
.site-footer {
  padding: var(--space-8) var(--space-4);
  text-align: center;
  color: var(--text-tertiary);
  font-size: 0.8125rem;
  border-top: 1px solid var(--border-color);
  margin-top: var(--space-16);
}

/* Login page */
.login-wrapper {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  background: var(--bg-page);
}

.login-card {
  width: 100%;
  max-width: 400px;
}

.login-card .login-header {
  text-align: center;
  margin-bottom: var(--space-8);
}

.login-card .login-header .brand-icon {
  width: 48px;
  height: 48px;
  background: var(--color-primary);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFFFFF;
  font-size: 1.5rem;
  margin: 0 auto var(--space-4);
}

.login-card .login-header h1 {
  font-size: 1.375rem;
  margin-bottom: var(--space-1);
}

.login-card .login-header p {
  color: var(--text-secondary);
  font-size: 0.875rem;
}

/* Chart containers */
.chart-container {
  position: relative;
  width: 100%;
}

.chart-container canvas {
  width: 100% !important;
  height: auto !important;
}

/* Filter bar */
.filter-bar {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-bottom: var(--space-4);
}

.filter-bar .form-input,
.filter-bar .form-select {
  width: auto;
  min-width: 160px;
}

/* Password input with toggle */
.password-wrapper {
  position: relative;
}

.password-wrapper .form-input {
  padding-right: 44px;
}

.password-toggle {
  position: absolute;
  right: 8px;
  top: 50%;
  transform: translateY(-50%);
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--text-tertiary);
  cursor: pointer;
}

.password-toggle:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

/* Scrollbar styling */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--border-color-strong);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-tertiary);
}

/* Print styles */
@media print {
  .top-nav, .sidebar, .admin-topbar, .toast-container {
    display: none !important;
  }

  body {
    background: #fff;
    color: #000;
  }

  .admin-main {
    margin-left: 0;
  }
}