/* ==========================================
   Layout CSS — Design Tokens + Admin Layout
   ========================================== */

/* CSS Variables — Gold/Parchment Design System */
:root {
  /* Brand Colors */
  --gold: #EDC348;
  --gold-dim: #d4a930;
  --gold-glow: rgba(237, 195, 72, .18);

  /* Text Colors */
  --ink: #1a1a1a;
  --ink-soft: #4a4a4a;
  --ink-muted: #8a8a8a;

  /* Background Colors */
  --parchment: #faf8f4;
  --parchment-deep: #f0ece4;

  /* Surface Colors */
  --card: #ffffff;
  --card-border: rgba(0,0,0,.06);

  /* Status Colors */
  --danger: #c0392b;
  --danger-bg: rgba(192,57,43,.06);
  --success: #27714a;
  --success-bg: #e8f5ee;
  --warning: #b8860b;
  --warning-bg: #fef9e7;

  /* Typography */
  --font-display: 'Noto Serif TC', 'Georgia', serif;
  --font-body: 'Noto Sans TC', -apple-system, sans-serif;

  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;

  /* Layout Dimensions */
  --sidebar-width: 256px;
  --topbar-height: 64px;

  /* Border Radius */
  --radius: 12px;
  --radius-lg: 8px;
  --radius-md: 6px;
  --radius-sm: 4px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0,0,0,.05), 0 1px 2px rgba(0,0,0,.04);
  --shadow-md: 0 4px 16px rgba(0,0,0,.06), 0 1px 3px rgba(0,0,0,.04);
  --shadow-lg: 0 12px 40px rgba(0,0,0,.08), 0 4px 12px rgba(0,0,0,.04);

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(.4,0,.2,1);
  --transition-base: 200ms cubic-bezier(.4,0,.2,1);
  --transition-slow: 300ms cubic-bezier(.4,0,.2,1);
}

/* CSS Reset */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-body);
  background: var(--parchment);
  color: var(--ink);
  font-size: 14px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Subtle paper grain texture */
body::before {
  content: '';
  position: fixed; inset: 0; z-index: -1;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.025'/%3E%3C/svg%3E");
  background-size: 256px;
  pointer-events: none;
}

/* Admin Layout Structure */
.admin-layout {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* Main Area */
.main-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  min-width: 0;
}

/* Workspace */
.workspace {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  background: var(--parchment);
  padding: var(--spacing-xl);
}

.workspace::-webkit-scrollbar { width: 8px; }
.workspace::-webkit-scrollbar-track { background: var(--parchment-deep); }
.workspace::-webkit-scrollbar-thumb { background: rgba(0,0,0,.1); border-radius: 9999px; }
.workspace::-webkit-scrollbar-thumb:hover { background: var(--ink-muted); }

.workspace-container {
  max-width: 1100px;
  margin: 0 auto;
}

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

.workspace-title {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--ink);
}

.workspace-title-sub {
  font-size: .82rem;
  color: var(--ink-muted);
  font-weight: 300;
  margin-top: 2px;
}

/* Card Component */
.card {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  animation: fadeSlideUp .5s ease both;
  transition: box-shadow var(--transition-base);
}

.card-header {
  padding: 20px var(--spacing-lg);
  border-bottom: 1px solid var(--card-border);
}

.card-header h3 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--ink);
  display: flex;
  align-items: center;
  gap: 10px;
}

.card-header h3::before {
  content: '';
  display: block;
  width: 3px;
  height: 18px;
  background: var(--gold);
  border-radius: 2px;
}

.card-body {
  padding: var(--spacing-lg);
}

/* Loading State */
.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 300px;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--parchment-deep);
  border-top-color: var(--gold);
  border-radius: 9999px;
  animation: spin 0.8s linear infinite;
}

/* Animations */
@keyframes fadeSlideUp {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeSlideDown {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

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

@keyframes shimmer {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

/* Responsive */
@media (max-width: 768px) {
  .workspace { padding: var(--spacing-md); }
  .workspace-header { flex-direction: column; align-items: flex-start; gap: 12px; }
}