:root {
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-card: rgba(22, 27, 34, 0.9);
  --bg-card-solid: #1c2333;
  --bg-hover: #252d3d;
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --text-muted: #6e7681;
  --accent: #2ea043;
  --accent-hover: #3fb950;
  --accent-glow: rgba(46, 160, 67, 0.15);
  --accent-dark: #238636;
  --danger: #da3633;
  --danger-hover: #e53935;
  --warning: #ffa726;
  --border: rgba(48, 54, 61, 0.6);
  --shadow: rgba(0, 0, 0, 0.4);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 16px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --accent-gold: #d29922;
  --accent-blue: #58a6ff;
  --accent-purple: #bc8cff;
}

[data-theme="light"] {
  --bg-primary: #f6f8fa;
  --bg-secondary: #eef1f5;
  --bg-card: rgba(255, 255, 255, 0.95);
  --bg-card-solid: #ffffff;
  --bg-hover: #f0f4f8;
  --text-primary: #1c2128;
  --text-secondary: #57606a;
  --text-muted: #6e7681;
  --accent: #2ea043;
  --accent-hover: #238636;
  --accent-glow: rgba(46, 160, 67, 0.1);
  --accent-dark: #238636;
  --danger: #da3633;
  --danger-hover: #e53935;
  --warning: #ffa726;
  --border: rgba(208, 215, 222, 0.6);
  --shadow: rgba(0, 0, 0, 0.06);
  --accent-gold: #d29922;
  --accent-blue: #58a6ff;
  --accent-purple: #bc8cff;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  animation: pageIn 0.3s ease;
}

::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }

::selection { background: var(--accent); color: #fff; }

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

.logo { font-size: 2rem; font-weight: 800; letter-spacing: -0.02em; }
.logo span { color: var(--accent); }

.landing {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 2rem;
  position: relative;
  overflow: hidden;
  background: radial-gradient(ellipse at 50% 30%, var(--accent-glow), transparent 60%);
}

.landing::before {
  content: '';
  position: absolute; inset: 0;
  background: url("data:image/svg+xml,%3Csvg viewBox='0 0 1024 1024' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E") center/cover;
  opacity: 0.03;
  pointer-events: none;
}

.landing-content { animation: fadeUp 0.8s ease; position: relative; z-index: 1; max-width: 700px; }
.landing h1 { font-size: 3.5rem; font-weight: 900; letter-spacing: -0.03em; line-height: 1.1; }
.landing h1 span { color: var(--accent); }
.landing .tagline { font-size: 1.2rem; color: var(--text-secondary); margin: 1rem 0 2.5rem; line-height: 1.7; }
.tagline { color: var(--text-secondary); font-size: 1.15rem; margin: 0.75rem 0 2rem; }

.landing-buttons { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }

.landing-nav {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin: 1.5rem 0 2.5rem;
}
.landing-nav-link {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 2rem;
  text-align: center;
  transition: all var(--transition);
  color: var(--text);
  font-size: 1.05rem;
  font-weight: 600;
  text-decoration: none;
  min-width: 140px;
}
.landing-nav-link:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  color: var(--accent);
}

.btn {
  padding: 0.7rem 1.75rem;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  letter-spacing: 0.01em;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  color: #fff;
  box-shadow: 0 4px 16px var(--accent-glow);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px var(--accent-glow);
}

.btn-secondary {
  background: transparent;
  color: var(--accent);
  border: 2px solid var(--accent);
}
.btn-secondary:hover {
  background: var(--accent);
  color: #fff;
  transform: translateY(-2px);
}

.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { background: var(--danger-hover); transform: translateY(-1px); }

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

.btn-small { padding: 0.35rem 0.85rem; font-size: 0.8rem; }
.btn-sm { padding: 0.5rem 1rem; font-size: 0.85rem; }

.theme-toggle {
  position: fixed; top: 1rem; right: 1rem;
  font-size: 1.4rem; cursor: pointer;
  padding: 0.5rem; border-radius: 50%;
  background: var(--bg-card); border: 1px solid var(--border);
  backdrop-filter: blur(12px); z-index: 100;
  transition: all var(--transition);
}
.theme-toggle:hover { transform: scale(1.1); }

.auth-page {
  display: flex; align-items: center; justify-content: center;
  min-height: 100vh; padding: 1rem;
  background: radial-gradient(ellipse at 50% 40%, var(--accent-glow), transparent 60%);
}

.auth-card {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  width: 100%; max-width: 420px;
  box-shadow: 0 8px 48px var(--shadow);
}

.form-group { margin-bottom: 1.2rem; }
.form-group label {
  display: block; margin-bottom: 0.35rem;
  color: var(--text-secondary); font-size: 0.85rem; font-weight: 500;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%; padding: 0.7rem 1rem;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg-primary);
  color: var(--text-primary);
  font-size: 0.95rem;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.form-group textarea { min-height: 100px; resize: vertical; }

.auth-switch { text-align: center; margin-top: 1.2rem; color: var(--text-secondary); font-size: 0.88rem; }

.error-msg { color: var(--danger); font-size: 0.85rem; margin-top: 0.5rem; text-align: center; }
.success-msg { color: var(--accent); font-size: 0.85rem; margin-top: 0.5rem; text-align: center; }

.navbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 0.6rem 2rem;
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 100;
}

.nav-brand { font-size: 1.2rem; font-weight: 800; letter-spacing: -0.02em; }
.nav-brand span { color: var(--accent); }

.nav-links { display: flex; gap: 0.25rem; }

.nav-links a {
  color: var(--text-secondary);
  font-weight: 500; font-size: 0.9rem;
  padding: 0.4rem 0.9rem;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}
.nav-links a:hover, .nav-links a.active {
  color: var(--text-primary);
  background: var(--accent-glow);
}

.nav-user { display: flex; align-items: center; gap: 0.75rem; }

.credits-badge {
  background: rgba(255, 167, 38, 0.1);
  padding: 0.25rem 0.7rem;
  border-radius: 20px;
  font-size: 0.82rem; font-weight: 600;
  color: var(--warning);
  border: 1px solid rgba(255, 167, 38, 0.2);
}

.xp-badge {
  background: var(--accent-glow);
  padding: 0.25rem 0.7rem;
  border-radius: 20px;
  font-size: 0.82rem; font-weight: 600;
  color: var(--accent);
  border: 1px solid rgba(76, 175, 80, 0.2);
}

.user-dropdown { position: relative; }

.user-btn {
  display: flex; align-items: center; gap: 0.4rem;
  padding: 0.45rem 0.9rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  cursor: pointer;
  font-size: 0.88rem;
  transition: all var(--transition);
}
.user-btn:hover { background: var(--bg-hover); border-color: var(--accent); }

.badge-tier { font-size: 0.65rem; padding: 0.1rem 0.35rem; border-radius: 4px; font-weight: 800; text-transform: uppercase; letter-spacing: 0.04em; }
.badge-tier.free { background: var(--bg-hover); color: var(--text-muted); }
.badge-tier.plus { background: var(--accent-blue); color: #fff; }
.badge-tier.pro { background: var(--accent); color: #fff; }
.badge-tier.ultra { background: var(--accent-gold); color: #000; }

.dropdown-menu {
  display: none;
  position: absolute; top: 100%; right: 0;
  margin-top: 0.4rem;
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  min-width: 190px;
  box-shadow: 0 12px 40px var(--shadow);
  z-index: 200;
  overflow: hidden;
}
.dropdown-menu.show { display: block; animation: fadeIn 0.15s ease; }

.dropdown-menu a {
  display: flex; align-items: center; gap: 0.5rem;
  padding: 0.65rem 1rem;
  color: var(--text-primary);
  font-size: 0.88rem;
  transition: background var(--transition);
}
.dropdown-menu a:hover { background: var(--bg-hover); }
.dropdown-menu a .icon { font-size: 1.1rem; }

.dropdown-menu hr { border: none; border-top: 1px solid var(--border); margin: 0.25rem 0; }

.theme-toggle-small { font-size: 1.1rem; cursor: pointer; background: none; border: none; padding: 0.3rem; opacity: 0.7; transition: opacity var(--transition); }
.theme-toggle-small:hover { opacity: 1; }

.admin-tag { font-size: 0.65rem; padding: 0.12rem 0.4rem; background: var(--danger); color: #fff; border-radius: 4px; vertical-align: middle; margin-left: 0.3rem; font-weight: 700; }

.ad-banner { text-align: center; padding: 0.75rem; background: var(--bg-card); backdrop-filter: blur(8px); border-top: 1px solid var(--border); margin-top: auto; }
#adPlaceholder { color: var(--text-muted); font-size: 0.82rem; }
.ad-banner img { max-width: 100%; max-height: 80px; border-radius: var(--radius-sm); }

.status-msg { font-size: 0.85rem; margin-top: 0.5rem; }

/* Modal */
.modal-overlay {
  display: none;
  position: fixed; inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  z-index: 1000;
  align-items: center; justify-content: center;
  padding: 1rem;
}
.modal-overlay.show { display: flex; animation: fadeIn 0.2s ease; }

.modal {
  background: var(--bg-card-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  width: 100%; max-width: 480px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 16px 64px var(--shadow);
  animation: slideUp 0.25s ease;
}

.modal h2 { font-size: 1.3rem; margin-bottom: 1.5rem; }

.modal-close {
  position: absolute; top: 1rem; right: 1rem;
  background: none; border: none;
  font-size: 1.4rem; cursor: pointer;
  color: var(--text-muted);
  transition: color var(--transition);
}
.modal-close:hover { color: var(--text-primary); }

.modal .form-group { margin-bottom: 1rem; }
.modal .btn { width: 100%; margin-top: 0.5rem; }

/* Modal header with close */
.modal-header {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 1.5rem;
}
.modal-header h2 { margin: 0; }

/* Color picker grid */
.color-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 0.4rem;
  margin: 0.5rem 0;
}
.color-swatch {
  width: 100%; aspect-ratio: 1;
  border-radius: var(--radius-sm);
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
}
.color-swatch:hover { transform: scale(1.1); }
.color-swatch.selected { border-color: var(--text-primary); }

/* Sidebar toggle */
.sidebar-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 1.2rem;
  cursor: pointer;
}

/* Mobile menu button */
.mobile-menu-btn {
  display: none;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 1.2rem;
  cursor: pointer;
}

/* Page transition */
@keyframes pageIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes fadeUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
@keyframes slideUp { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: translateY(0); } }

@media (max-width: 768px) {
  .mobile-menu-btn { display: flex; }
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 0.5rem;
  }
  .nav-links.show { display: flex; }
  .nav-links a { padding: 0.7rem 1rem; }
  .home-layout { flex-direction: column; }
  .sidebar { display: none; width: 100%; border-right: none; border-bottom: 1px solid var(--border); }
  .sidebar.show { display: block; }
  .sidebar-toggle { display: flex; }
  .main-content { padding: 1rem; max-width: 100%; }
  .games-grid { grid-template-columns: 1fr; }
  .admin-sidebar { width: 56px; }
  .admin-sidebar a { padding: 0.7rem; justify-content: center; gap: 0; }
  .admin-sidebar a .nav-icon { font-size: 1.2rem; }
  .admin-sidebar a span:not(.nav-icon) { display: none; }
  .admin-content { padding: 1rem; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .modal { padding: 1.5rem; margin: 0.5rem; max-width: 100%; }
  .landing-content { padding: 1rem; }
  .landing h1 { font-size: 2rem; }
  .landing-nav { flex-direction: column; align-items: center; }
  .landing-nav-link { min-width: 200px; }
}