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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  color: #333;
}

.navbar {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  gap: 1rem;
  align-items: center;
}

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

.user-name {
  font-weight: 500;
  color: #555;
}

.main-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
}

.auth-container {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: calc(100vh - 200px);
}

.auth-card {
  background: white;
  border-radius: 16px;
  padding: 2.5rem;
  width: 100%;
  max-width: 420px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.auth-tabs {
  display: flex;
  gap: 1rem;
  margin-bottom: 2rem;
  border-bottom: 2px solid #eee;
}

.tab-btn {
  flex: 1;
  padding: 0.75rem;
  border: none;
  background: none;
  font-size: 1rem;
  font-weight: 500;
  color: #999;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: all 0.3s ease;
}

.tab-btn.active {
  color: #667eea;
  border-bottom-color: #667eea;
}

.auth-form {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.auth-form.hidden {
  display: none;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.form-group label {
  font-size: 0.875rem;
  font-weight: 500;
  color: #555;
}

.form-group input,
.form-group textarea {
  padding: 0.75rem 1rem;
  border: 2px solid #e8e8e8;
  border-radius: 8px;
  font-size: 1rem;
  transition: all 0.3s ease;
  font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: #667eea;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-primary {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
  background: #f5f5f5;
  color: #555;
}

.btn-secondary:hover {
  background: #e8e8e8;
}

.btn-danger {
  background: #ef4444;
  color: white;
}

.btn-danger:hover {
  background: #dc2626;
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.error-msg {
  color: #ef4444;
  font-size: 0.875rem;
  text-align: center;
  min-height: 1.25rem;
}

.dashboard {
  animation: fadeIn 0.3s ease;
}

.dashboard.hidden {
  display: none;
}

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

.dashboard-header {
  text-align: center;
  margin-bottom: 2.5rem;
  color: white;
}

.dashboard-header h2 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.subtitle {
  opacity: 0.9;
}

.items-section {
  display: grid;
  grid-template-columns: 350px 1fr;
  gap: 2rem;
}

.add-item-card,
.items-list {
  background: white;
  border-radius: 16px;
  padding: 1.5rem;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.add-item-card h3,
.items-list h3 {
  margin-bottom: 1rem;
  color: #333;
}

.items-grid {
  display: grid;
  gap: 1rem;
}

.item-card {
  background: #f9fafb;
  border-radius: 12px;
  padding: 1.25rem;
  border-left: 4px solid #667eea;
  transition: all 0.3s ease;
}

.item-card:hover {
  transform: translateX(4px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.item-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: #333;
  margin-bottom: 0.5rem;
}

.item-content {
  color: #666;
  font-size: 0.875rem;
  margin-bottom: 1rem;
  line-height: 1.5;
}

.item-date {
  color: #999;
  font-size: 0.75rem;
  margin-bottom: 0.75rem;
}

.item-actions {
  display: flex;
  gap: 0.5rem;
}

.empty-state {
  text-align: center;
  color: #999;
  padding: 3rem 1rem;
}

.empty-state.hidden {
  display: none;
}

.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
  animation: fadeIn 0.2s ease;
}

.modal.hidden {
  display: none;
}

.modal-content {
  background: white;
  border-radius: 16px;
  padding: 2rem;
  width: 90%;
  max-width: 500px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  animation: slideUp 0.3s ease;
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.modal-content h3 {
  margin-bottom: 1.5rem;
}

.modal-actions {
  display: flex;
  gap: 1rem;
  justify-content: flex-end;
  margin-top: 1.5rem;
}

@media (max-width: 768px) {
  .nav-container {
    padding: 1rem;
  }

  .main-content {
    padding: 1rem;
  }

  .items-section {
    grid-template-columns: 1fr;
  }

  .auth-card {
    padding: 1.5rem;
  }
}