:root {
  --bg-primary: #0a0f1e;
  --bg-secondary: #0c1222;
  --bg-card: rgba(18, 25, 45, 0.95);
  --bg-input: rgba(10, 14, 23, 0.7);
  --border-subtle: rgba(72, 187, 255, 0.1);
  --border-medium: rgba(72, 187, 255, 0.15);
  --border-strong: rgba(72, 187, 255, 0.3);
  --text-primary: #f0f4ff;
  --text-secondary: #b9c3e6;
  --text-muted: #6b7280;
  --accent-primary: #3b82f6;
  --accent-blue: #3b82f6;
  --accent-green: #22c55e;
  --accent-red: #ef4444;
  --accent-yellow: #f59e0b;
  --streak-fire: linear-gradient(135deg, #FF6B35, #F5C842);
  --border-radius: 1rem;
  --border-radius-sm: 0.75rem;
  --border-radius-lg: 1.5rem;
  --transition-fast: 0.2s;
  --transition-base: 0.3s;
  --font-display: 'Inter', sans-serif;
  --font-body: 'Inter', sans-serif;
}

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

body {
  font-family: var(--font-body);
  background: linear-gradient(145deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
  color: var(--text-primary);
  min-height: 100vh;
}

/* Auth Styles */
.auth-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.auth-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border-radius: var(--border-radius-lg);
  padding: 40px 36px;
  max-width: 440px;
  width: 100%;
  border: 1px solid var(--border-medium);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.5);
}

.auth-header {
  text-align: center;
  margin-bottom: 32px;
}

.logo-gradient {
  font-size: 48px;
  font-weight: 800;
  background: var(--streak-fire);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  letter-spacing: -2px;
}

.tagline {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-top: 6px;
}

.auth-tabs {
  display: flex;
  background: var(--bg-input);
  border-radius: var(--border-radius-sm);
  padding: 4px;
  margin-bottom: 28px;
}

.auth-tab {
  flex: 1;
  padding: 10px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-secondary);
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.auth-tab.active {
  background: var(--bg-card);
  color: var(--text-primary);
  box-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.auth-form {
  display: none;
}

.auth-form.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

.input-group {
  position: relative;
  margin-bottom: 12px;
}

.input-icon {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 14px;
}

.form-input {
  width: 100%;
  padding: 14px 14px 14px 40px;
  background: var(--bg-input);
  border: 1px solid var(--border-medium);
  border-radius: var(--border-radius-sm);
  color: var(--text-primary);
  font-size: 14px;
  font-family: inherit;
  transition: all var(--transition-fast);
}

.form-input:focus {
  outline: none;
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}

.password-toggle {
  position: absolute;
  right: 14px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
}

.btn-primary {
  background: linear-gradient(95deg, var(--accent-primary), #2563eb);
  border: none;
  padding: 14px;
  border-radius: var(--border-radius-sm);
  font-weight: 700;
  color: white;
  cursor: pointer;
  font-family: inherit;
  transition: all var(--transition-base);
}

.btn-primary:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(59, 130, 246, 0.4);
}

.btn-full {
  width: 100%;
}

.btn-google {
  width: 100%;
  padding: 12px;
  background: var(--bg-input);
  border: 1px solid var(--border-medium);
  border-radius: var(--border-radius-sm);
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-google:hover {
  background: var(--border-medium);
}

.divider {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 20px 0;
  color: var(--text-muted);
  font-size: 12px;
}

.divider::before,
.divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border-subtle);
}

.auth-switch {
  text-align: center;
  margin-top: 24px;
  font-size: 13px;
  color: var(--text-secondary);
}

.link-btn {
  background: none;
  border: none;
  color: var(--accent-primary);
  font-weight: 600;
  cursor: pointer;
  font-family: inherit;
}

/* Sidebar */
.sidebar {
  position: fixed;
  left: 0;
  top: 0;
  width: 260px;
  height: 100vh;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border-right: 1px solid var(--border-medium);
  padding: 2rem 1rem;
  display: flex;
  flex-direction: column;
  z-index: 100;
}

.nav-menu {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1rem;
  border-radius: 0.75rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all var(--transition-fast);
  font-weight: 500;
}

.nav-item i {
  font-size: 1.5rem;
  width: 28px;
}

.nav-item:hover,
.nav-item.active {
  background: rgba(59, 130, 246, 0.15);
  color: var(--accent-primary);
}

.sidebar-footer {
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
  margin-top: auto;
}

.user-info-sidebar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
}

.sidebar-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  object-fit: cover;
}

.logout-btn {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1rem;
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.3);
  border-radius: 0.75rem;
  color: #fca5a5;
  cursor: pointer;
  font-family: inherit;
  transition: var(--transition-fast);
}

.logout-btn:hover {
  background: rgba(239, 68, 68, 0.2);
}

/* Main Content */
.main-content {
  margin-left: 260px;
  max-width: 800px;
  padding: 2rem 1.5rem;
  width: 100%;
}

/* Bottom Navigation */
.bottom-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border-top: 1px solid var(--border-medium);
  padding: 0.75rem 1rem;
  justify-content: space-around;
  z-index: 100;
}

.bottom-nav .nav-item {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 0.5rem;
  font-size: 0.7rem;
}

/* Modal */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.8);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal.hidden {
  display: none;
}

.modal-content {
  background: var(--bg-card);
  border-radius: var(--border-radius-lg);
  max-width: 500px;
  width: 90%;
  max-height: 80vh;
  overflow: hidden;
  border: 1px solid var(--border-medium);
}

.modal-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-close {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 24px;
  cursor: pointer;
}

/* Responsive */
@media (max-width: 768px) {
  .sidebar {
    display: none;
  }
  
  .main-content {
    margin-left: 0;
    padding: 1rem 1rem 5rem;
  }
  
  .bottom-nav {
    display: flex;
  }
  
  .auth-card {
    padding: 28px 20px;
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}