/* ============================================
   GameVault - Design System
   ============================================ */

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

:root {
  /* Colors - Dark Mode (default) */
  --bg-primary: #0f0f1a;
  --bg-secondary: #1a1a2e;
  --bg-tertiary: #16213e;
  --bg-card: #1a1a2e;
  --bg-card-hover: #222240;
  --bg-input: #16213e;
  --bg-overlay: rgba(0,0,0,0.6);
  
  --text-primary: #e8e8f0;
  --text-secondary: #a0a0b8;
  --text-muted: #6b6b80;
  --text-inverse: #0f0f1a;
  
  --accent-primary: #6c5ce7;
  --accent-primary-hover: #5a4bd1;
  --accent-secondary: #00cec9;
  --accent-gradient: linear-gradient(135deg, #6c5ce7 0%, #a855f7 50%, #ec4899 100%);
  --accent-gradient-soft: linear-gradient(135deg, rgba(108,92,231,0.15) 0%, rgba(168,85,247,0.15) 50%, rgba(236,72,153,0.15) 100%);
  
  --success: #00b894;
  --warning: #fdcb6e;
  --danger: #ff6b6b;
  --info: #74b9ff;
  
  --border-color: rgba(255,255,255,0.08);
  --border-color-strong: rgba(255,255,255,0.15);
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.5);
  --shadow-glow: 0 0 30px rgba(108,92,231,0.2);
  
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;
  
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 400ms ease;
  
  --sidebar-width: 260px;
  --navbar-height: 64px;
  --container-max: 1200px;
}

/* Light Mode */
[data-theme="light"] {
  --bg-primary: #f5f5fa;
  --bg-secondary: #ffffff;
  --bg-tertiary: #eef0f6;
  --bg-card: #ffffff;
  --bg-card-hover: #f8f9fc;
  --bg-input: #f0f1f6;
  --bg-overlay: rgba(0,0,0,0.3);
  
  --text-primary: #1a1a2e;
  --text-secondary: #555570;
  --text-muted: #9090a8;
  --text-inverse: #ffffff;
  
  --accent-primary: #6c5ce7;
  --accent-primary-hover: #5a4bd1;
  --accent-gradient-soft: linear-gradient(135deg, rgba(108,92,231,0.08) 0%, rgba(168,85,247,0.08) 50%, rgba(236,72,153,0.08) 100%);
  
  --border-color: rgba(0,0,0,0.08);
  --border-color-strong: rgba(0,0,0,0.15);
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.12);
  --shadow-glow: 0 0 30px rgba(108,92,231,0.1);
}

/* --- Base --- */
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a { color: var(--accent-primary); text-decoration: none; transition: color var(--transition-fast); }
a:hover { color: var(--accent-primary-hover); }

img { max-width: 100%; height: auto; }
button { cursor: pointer; font-family: inherit; }
input, select, textarea { font-family: inherit; }

/* --- Layout --- */
.container { max-width: var(--container-max); margin: 0 auto; padding: 0 24px; }
.page-wrapper { min-height: 100vh; display: flex; flex-direction: column; }
.page-content { flex: 1; padding-top: var(--navbar-height); }

/* --- App Layout (Dashboard/Game Pages) --- */
.app-layout { display: flex; min-height: 100vh; }
.app-sidebar {
  width: var(--sidebar-width);
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  z-index: 100;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-normal);
}
.app-main { flex: 1; margin-left: var(--sidebar-width); min-height: 100vh; }
.app-header {
  height: var(--navbar-height);
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(20px);
}
.app-body { padding: 24px; }

/* Sidebar Logo */
.sidebar-logo {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 12px;
}
.sidebar-logo .logo-icon {
  width: 36px;
  height: 36px;
  background: var(--accent-gradient);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: white;
  font-weight: 700;
}
.sidebar-logo .logo-text {
  font-size: 18px;
  font-weight: 700;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Sidebar Nav */
.sidebar-nav { flex: 1; padding: 12px; overflow-y: auto; }
.sidebar-nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
  transition: all var(--transition-fast);
  margin-bottom: 2px;
  cursor: pointer;
}
.sidebar-nav-item:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}
.sidebar-nav-item.active {
  background: var(--accent-gradient-soft);
  color: var(--accent-primary);
}
.sidebar-nav-item .nav-icon { font-size: 18px; width: 24px; text-align: center; }
.sidebar-nav-section {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  padding: 16px 16px 8px;
}

/* Sidebar Footer */
.sidebar-footer {
  padding: 16px;
  border-top: 1px solid var(--border-color);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 24px;
  padding: 4px;
}
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--bg-overlay);
  z-index: 99;
}

/* --- Navbar (Landing Page) --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--navbar-height);
  background: rgba(15,15,26,0.8);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  display: flex;
  align-items: center;
}
[data-theme="light"] .navbar { background: rgba(245,245,250,0.8); }
.navbar-inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.navbar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 20px;
  color: var(--text-primary);
}
.navbar-brand .brand-icon {
  width: 32px;
  height: 32px;
  background: var(--accent-gradient);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 16px;
}
.navbar-links { display: flex; gap: 8px; align-items: center; }
.navbar-link {
  padding: 8px 16px;
  border-radius: var(--radius-full);
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
  transition: all var(--transition-fast);
}
.navbar-link:hover { color: var(--text-primary); background: var(--bg-tertiary); }

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 600;
  border: none;
  transition: all var(--transition-fast);
  white-space: nowrap;
  line-height: 1.4;
}
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-primary {
  background: var(--accent-gradient);
  color: white;
  box-shadow: 0 4px 15px rgba(108,92,231,0.3);
}
.btn-primary:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(108,92,231,0.4);
}
.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}
.btn-secondary:hover:not(:disabled) { background: var(--bg-card-hover); border-color: var(--border-color-strong); }
.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}
.btn-ghost:hover:not(:disabled) { background: var(--bg-tertiary); color: var(--text-primary); }
.btn-danger { background: var(--danger); color: white; }
.btn-danger:hover:not(:disabled) { background: #e55a5a; }
.btn-success { background: var(--success); color: white; }
.btn-success:hover:not(:disabled) { background: #00a884; }
.btn-sm { padding: 6px 14px; font-size: 13px; border-radius: var(--radius-sm); }
.btn-lg { padding: 14px 28px; font-size: 16px; }
.btn-icon { padding: 8px; width: 36px; height: 36px; border-radius: var(--radius-sm); }
.btn-icon.btn-lg { width: 44px; height: 44px; }
.btn-block { width: 100%; }

/* --- Cards --- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: all var(--transition-normal);
}
.card:hover { border-color: var(--border-color-strong); }
.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}
.card-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
}
.card-subtitle {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 4px;
}

/* Game Card */
.game-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-normal);
  cursor: pointer;
}
.game-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-primary);
  box-shadow: var(--shadow-glow);
}
.game-card-thumbnail {
  width: 100%;
  aspect-ratio: 16/10;
  background: var(--accent-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 48px;
  position: relative;
  overflow: hidden;
}
.game-card-thumbnail::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(transparent 60%, rgba(0,0,0,0.3));
}
.game-card-body { padding: 16px; }
.game-card-name {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
  color: var(--text-primary);
}
.game-card-desc {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 12px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.game-card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.game-card-plays {
  font-size: 12px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 4px;
}

/* --- Forms --- */
.form-group { margin-bottom: 20px; }
.form-label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
}
.form-input {
  width: 100%;
  padding: 10px 14px;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 14px;
  transition: all var(--transition-fast);
  outline: none;
}
.form-input:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px rgba(108,92,231,0.15);
}
.form-input::placeholder { color: var(--text-muted); }
.form-input.error { border-color: var(--danger); }
.form-error { font-size: 12px; color: var(--danger); margin-top: 4px; }
.form-hint { font-size: 12px; color: var(--text-muted); margin-top: 4px; }
.form-checkbox {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--text-secondary);
  cursor: pointer;
}
.form-checkbox input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--accent-primary);
}
.form-select {
  width: 100%;
  padding: 10px 14px;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 14px;
  outline: none;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%236b6b80' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}
.form-select:focus { border-color: var(--accent-primary); box-shadow: 0 0 0 3px rgba(108,92,231,0.15); }
textarea.form-input { min-height: 100px; resize: vertical; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* Search Input */
.search-box {
  position: relative;
}
.search-box .search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 16px;
  pointer-events: none;
}
.search-box .form-input { padding-left: 38px; }

/* --- Badge --- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 600;
  line-height: 1.4;
}
.badge-purple { background: rgba(108,92,231,0.15); color: #a78bfa; }
.badge-blue { background: rgba(59,130,246,0.15); color: #60a5fa; }
.badge-green { background: rgba(16,185,129,0.15); color: #34d399; }
.badge-orange { background: rgba(245,158,11,0.15); color: #fbbf24; }
.badge-red { background: rgba(239,68,68,0.15); color: #f87171; }
.badge-gray { background: rgba(107,107,128,0.15); color: #a0a0b8; }
[data-theme="light"] .badge-purple { background: rgba(108,92,231,0.12); color: #6c5ce7; }
[data-theme="light"] .badge-blue { background: rgba(59,130,246,0.12); color: #3b82f6; }
[data-theme="light"] .badge-green { background: rgba(16,185,129,0.12); color: #10b981; }
[data-theme="light"] .badge-orange { background: rgba(245,158,11,0.12); color: #d97706; }
[data-theme="light"] .badge-red { background: rgba(239,68,68,0.12); color: #ef4444; }

/* --- Stats Card --- */
.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 20px;
  display: flex;
  align-items: center;
  gap: 16px;
}
.stat-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
}
.stat-icon.purple { background: rgba(108,92,231,0.15); }
.stat-icon.blue { background: rgba(59,130,246,0.15); }
.stat-icon.green { background: rgba(16,185,129,0.15); }
.stat-icon.orange { background: rgba(245,158,11,0.15); }
.stat-value { font-size: 24px; font-weight: 700; color: var(--text-primary); line-height: 1.2; }
.stat-label { font-size: 13px; color: var(--text-muted); margin-top: 2px; }

/* --- Progress Bar --- */
.progress-bar {
  width: 100%;
  height: 8px;
  background: var(--bg-tertiary);
  border-radius: var(--radius-full);
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: var(--accent-gradient);
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}
.progress-bar.lg { height: 12px; }
.progress-bar.sm { height: 4px; }

/* --- Table --- */
.table-wrapper { overflow-x: auto; }
table {
  width: 100%;
  border-collapse: collapse;
}
table th {
  padding: 12px 16px;
  text-align: left;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border-color);
  white-space: nowrap;
}
table td {
  padding: 12px 16px;
  font-size: 14px;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-color);
}
table tr:hover td { background: var(--bg-tertiary); }

/* --- Tabs --- */
.tabs {
  display: flex;
  gap: 4px;
  padding: 4px;
  background: var(--bg-tertiary);
  border-radius: var(--radius-md);
  overflow-x: auto;
}
.tab {
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
  border: none;
  background: none;
}
.tab:hover { color: var(--text-primary); }
.tab.active {
  background: var(--bg-card);
  color: var(--text-primary);
  box-shadow: var(--shadow-sm);
}

/* --- Modal --- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: var(--bg-overlay);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}
.modal-overlay.active { opacity: 1; visibility: visible; }
.modal {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  width: 100%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  transform: translateY(20px) scale(0.95);
  transition: transform var(--transition-normal);
}
.modal-overlay.active .modal { transform: translateY(0) scale(1); }
.modal-header {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.modal-title { font-size: 18px; font-weight: 600; }
.modal-close {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 20px;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.modal-close:hover { background: var(--bg-tertiary); color: var(--text-primary); }
.modal-body { padding: 24px; }
.modal-footer {
  padding: 16px 24px;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: flex-end;
  gap: 8px;
}

/* --- Toast --- */
.toast-container {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 10000;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.toast {
  padding: 12px 20px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 500;
  color: white;
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 280px;
  max-width: 400px;
  box-shadow: var(--shadow-lg);
  animation: toastIn 0.3s ease, toastOut 0.3s ease forwards;
  animation-delay: 0s, 3.5s;
}
.toast-success { background: var(--success); }
.toast-error { background: var(--danger); }
.toast-warning { background: var(--warning); color: #1a1a2e; }
.toast-info { background: var(--info); }

@keyframes toastIn {
  from { opacity: 0; transform: translateX(100px); }
  to { opacity: 1; transform: translateX(0); }
}
@keyframes toastOut {
  from { opacity: 1; transform: translateX(0); }
  to { opacity: 0; transform: translateX(100px); }
}

/* --- Loading / Skeleton --- */
.skeleton {
  background: linear-gradient(90deg, var(--bg-tertiary) 25%, var(--bg-card-hover) 50%, var(--bg-tertiary) 75%);
  background-size: 200% 100%;
  animation: skeleton 1.5s infinite;
  border-radius: var(--radius-sm);
}
@keyframes skeleton {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}
.skeleton-text { height: 14px; margin-bottom: 8px; }
.skeleton-text:last-child { width: 60%; }
.skeleton-circle { border-radius: 50%; }
.skeleton-card { height: 200px; border-radius: var(--radius-lg); }
.spinner {
  width: 32px;
  height: 32px;
  border: 3px solid var(--border-color);
  border-top-color: var(--accent-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.loading-overlay {
  position: absolute;
  inset: 0;
  background: var(--bg-overlay);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  border-radius: inherit;
}

/* --- Empty State --- */
.empty-state {
  text-align: center;
  padding: 60px 20px;
}
.empty-state-icon { font-size: 48px; margin-bottom: 16px; opacity: 0.5; }
.empty-state-title { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
.empty-state-text { font-size: 14px; color: var(--text-muted); max-width: 400px; margin: 0 auto; }

/* --- Avatar --- */
.avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  object-fit: cover;
  background: var(--bg-tertiary);
}
.avatar.sm { width: 32px; height: 32px; }
.avatar.lg { width: 56px; height: 56px; }
.avatar.xl { width: 80px; height: 80px; }
.avatar-xxl { width: 120px; height: 120px; }

/* --- Grid Layouts --- */
.grid { display: grid; gap: 16px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-games { grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); }

/* --- Flex Utilities --- */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.gap-4 { gap: 4px; }
.gap-8 { gap: 8px; }
.gap-12 { gap: 12px; }
.gap-16 { gap: 16px; }
.gap-24 { gap: 24px; }

/* --- Spacing --- */
.mt-4 { margin-top: 4px; }
.mt-8 { margin-top: 8px; }
.mt-12 { margin-top: 12px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mb-4 { margin-bottom: 4px; }
.mb-8 { margin-bottom: 8px; }
.mb-12 { margin-bottom: 12px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.mb-32 { margin-bottom: 32px; }

/* --- Text --- */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-sm { font-size: 13px; }
.text-xs { font-size: 12px; }
.text-lg { font-size: 18px; }
.text-xl { font-size: 24px; }
.text-2xl { font-size: 32px; }
.text-3xl { font-size: 40px; }
.font-bold { font-weight: 700; }
.font-semibold { font-weight: 600; }
.text-muted { color: var(--text-muted); }
.text-secondary { color: var(--text-secondary); }
.text-accent { color: var(--accent-primary); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-warning { color: var(--warning); }
.gradient-text {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* --- Section --- */
.section-title {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* --- Card User Info --- */
.user-info-card {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  transition: background var(--transition-fast);
}
.user-info-card:hover { background: var(--bg-tertiary); }

/* --- Leaderboard --- */
.leaderboard-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  transition: background var(--transition-fast);
}
.leaderboard-item:hover { background: var(--bg-tertiary); }
.leaderboard-rank {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  font-weight: 700;
  background: var(--bg-tertiary);
  color: var(--text-muted);
}
.leaderboard-rank.top-1 { background: linear-gradient(135deg, #fbbf24, #f59e0b); color: #1a1a2e; }
.leaderboard-rank.top-2 { background: linear-gradient(135deg, #94a3b8, #64748b); color: white; }
.leaderboard-rank.top-3 { background: linear-gradient(135deg, #d97706, #b45309); color: white; }

/* --- Achievement --- */
.achievement-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  transition: all var(--transition-normal);
}
.achievement-card.locked { opacity: 0.5; filter: grayscale(0.5); }
.achievement-card:hover { border-color: var(--border-color-strong); }
.achievement-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: var(--bg-tertiary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  flex-shrink: 0;
}
.achievement-card:not(.locked) .achievement-icon {
  background: var(--accent-gradient-soft);
}
.achievement-info { flex: 1; min-width: 0; }
.achievement-name { font-size: 15px; font-weight: 600; margin-bottom: 2px; }
.achievement-desc { font-size: 13px; color: var(--text-muted); }
.achievement-rewards {
  display: flex;
  gap: 8px;
  margin-top: 8px;
}
.achievement-reward {
  font-size: 12px;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: var(--bg-tertiary);
  color: var(--text-secondary);
}

/* --- Theme Toggle --- */
.theme-toggle {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  background: none;
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  font-size: 18px;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.theme-toggle:hover { background: var(--bg-tertiary); color: var(--text-primary); }

/* --- Hero Section --- */
.hero {
  min-height: calc(100vh - var(--navbar-height));
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 60px 24px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  width: 600px;
  height: 600px;
  background: var(--accent-gradient);
  border-radius: 50%;
  filter: blur(150px);
  opacity: 0.15;
  top: -200px;
  right: -100px;
}
.hero::after {
  content: '';
  position: absolute;
  width: 400px;
  height: 400px;
  background: linear-gradient(135deg, #ec4899, #8b5cf6);
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.1;
  bottom: -150px;
  left: -50px;
}
.hero-content { position: relative; z-index: 1; max-width: 640px; }
.hero-title {
  font-size: clamp(32px, 6vw, 56px);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 20px;
}
.hero-subtitle {
  font-size: clamp(16px, 2.5vw, 20px);
  color: var(--text-secondary);
  margin-bottom: 32px;
  line-height: 1.6;
}
.hero-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.hero-stats {
  display: flex;
  justify-content: center;
  gap: 40px;
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--border-color);
}
.hero-stat-value { font-size: 28px; font-weight: 700; }
.hero-stat-label { font-size: 13px; color: var(--text-muted); margin-top: 4px; }

/* --- Footer --- */
.footer {
  border-top: 1px solid var(--border-color);
  padding: 32px 24px;
  text-align: center;
}
.footer-text { font-size: 13px; color: var(--text-muted); }
.footer-links { display: flex; gap: 20px; justify-content: center; margin-bottom: 12px; }
.footer-link { font-size: 13px; color: var(--text-secondary); }

/* --- Page Titles --- */
.page-header {
  margin-bottom: 24px;
}
.page-title {
  font-size: 24px;
  font-weight: 700;
}
.page-subtitle {
  font-size: 14px;
  color: var(--text-muted);
  margin-top: 4px;
}

/* --- Auth Pages --- */
.auth-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  position: relative;
}
.auth-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 40px;
  width: 100%;
  max-width: 420px;
  box-shadow: var(--shadow-lg);
}
.auth-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-bottom: 32px;
}
.auth-title {
  font-size: 24px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 8px;
}
.auth-subtitle {
  font-size: 14px;
  color: var(--text-muted);
  text-align: center;
  margin-bottom: 24px;
}
.auth-divider {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 20px 0;
  color: var(--text-muted);
  font-size: 13px;
}
.auth-divider::before,
.auth-divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border-color);
}
.auth-footer {
  text-align: center;
  font-size: 14px;
  color: var(--text-muted);
  margin-top: 24px;
}

/* --- Game Page --- */
.game-container {
  max-width: 800px;
  margin: 0 auto;
  padding: 24px;
}
.game-area {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 24px;
  min-height: 400px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}
.game-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 24px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  margin-bottom: 16px;
  flex-wrap: wrap;
  gap: 12px;
}
.game-score {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 700;
}
.game-score .score-label { font-size: 13px; color: var(--text-muted); font-weight: 500; }
.game-over-overlay {
  position: absolute;
  inset: 0;
  background: var(--bg-overlay);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: inherit;
  z-index: 10;
}
.game-result {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 40px;
  text-align: center;
  max-width: 400px;
  width: 100%;
  box-shadow: var(--shadow-lg);
}
.game-result-score {
  font-size: 48px;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin: 16px 0;
}

/* --- Pagination --- */
.pagination {
  display: flex;
  align-items: center;
  gap: 4px;
  justify-content: center;
}
.page-btn {
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-secondary);
  font-size: 14px;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.page-btn:hover { background: var(--bg-tertiary); color: var(--text-primary); }
.page-btn.active {
  background: var(--accent-primary);
  color: white;
  border-color: var(--accent-primary);
}
.page-btn:disabled { opacity: 0.4; cursor: not-allowed; }

/* --- Game Thumbnail Color Variants --- */
.thumb-memory { background: linear-gradient(135deg, #6c5ce7, #a855f7); }
.thumb-snake { background: linear-gradient(135deg, #00b894, #00cec9); }
.thumb-tictactoe { background: linear-gradient(135deg, #fd79a8, #e84393); }
.thumb-whackamole { background: linear-gradient(135deg, #fdcb6e, #f39c12); }
.thumb-puzzle { background: linear-gradient(135deg, #74b9ff, #0984e3); }

/* --- Responsive --- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .app-sidebar {
    transform: translateX(-100%);
  }
  .app-sidebar.open { transform: translateX(0); }
  .sidebar-overlay.active { display: block; }
  .mobile-menu-toggle { display: flex; }
  .app-main { margin-left: 0; }
  .app-body { padding: 16px; }
  
  .navbar-links { gap: 4px; }
  .navbar-link { padding: 6px 10px; font-size: 13px; }
  
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .grid-games { grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); }
  
  .hero-stats { gap: 20px; flex-wrap: wrap; }
  .hero-actions { flex-direction: column; align-items: center; }
  
  .form-row { grid-template-columns: 1fr; }
  
  .stat-card { padding: 16px; }
  .stat-value { font-size: 20px; }
  
  .card { padding: 16px; }
  .auth-card { padding: 24px; }
  
  .game-toolbar { padding: 8px 16px; }
  
  .modal { max-width: calc(100% - 32px); margin: 16px; }
  
  .page-title { font-size: 20px; }
  .section-title { font-size: 17px; }
  
  .toast { min-width: auto; max-width: calc(100vw - 40px); }
}

@media (max-width: 480px) {
  .grid-games { grid-template-columns: 1fr; }
  .hero { padding: 40px 16px; min-height: auto; }
  .hero-title { font-size: 28px; }
  .hero-subtitle { font-size: 15px; }
}

/* --- Animations --- */
.fade-in {
  animation: fadeIn 0.3s ease;
}
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
.slide-in {
  animation: slideIn 0.3s ease;
}
@keyframes slideIn {
  from { opacity: 0; transform: translateX(-10px); }
  to { opacity: 1; transform: translateX(0); }
}

/* --- Scrollbar --- */
::-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-muted); }

/* --- Utility --- */
.hidden { display: none !important; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  border: 0;
}
.truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}