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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
    sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background: #fafafa;
  color: #262626;
  min-height: 100vh;
}

button {
  cursor: pointer;
  font-family: inherit;
}

input, textarea {
  font-family: inherit;
}

.header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 2rem;
  text-align: center;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.header h1 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.header p {
  opacity: 0.9;
}

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

.section {
  background: white;
  border-radius: 12px;
  padding: 1.5rem;
  margin-bottom: 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid #f0f0f0;
}

.section-header h2 {
  font-size: 1.5rem;
  color: #262626;
}

.btn-primary, .btn-secondary {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 8px;
  font-weight: 600;
  transition: all 0.2s;
}

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

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.btn-secondary {
  background: #f0f0f0;
  color: #262626;
}

.btn-secondary:hover {
  background: #e0e0e0;
}

.accounts-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1rem;
}

.account-card {
  border: 2px solid #e0e0e0;
  border-radius: 8px;
  padding: 1rem;
  cursor: pointer;
  transition: all 0.2s;
}

.account-card:hover {
  border-color: #667eea;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.2);
}

.account-card.active {
  border-color: #667eea;
  background: #f8f9ff;
}

.account-info h3 {
  color: #262626;
  margin-bottom: 0.5rem;
}

.account-info p {
  color: #666;
  font-size: 0.9rem;
  margin-bottom: 0.25rem;
}

.account-info small {
  color: #999;
  font-size: 0.75rem;
}

.status-badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  background: #4caf50;
  color: white;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 600;
}

.send-message {
  background: #f8f9ff;
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 2rem;
}

.send-message h3 {
  margin-bottom: 1rem;
  color: #262626;
}

.input, .textarea {
  width: 100%;
  padding: 0.75rem;
  border: 2px solid #e0e0e0;
  border-radius: 8px;
  margin-bottom: 1rem;
  font-size: 0.95rem;
  transition: border-color 0.2s;
}

.input:focus, .textarea:focus {
  outline: none;
  border-color: #667eea;
}

.textarea {
  resize: vertical;
  min-height: 80px;
}

.messages-list h3 {
  margin-bottom: 1rem;
  color: #262626;
}

.messages-container {
  max-height: 600px;
  overflow-y: auto;
}

.message-card {
  background: #f8f9ff;
  border-left: 4px solid #667eea;
  border-radius: 8px;
  padding: 1rem;
  margin-bottom: 1rem;
}

.message-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 0.5rem;
}

.message-header strong {
  color: #262626;
}

.message-time {
  color: #999;
  font-size: 0.85rem;
}

.message-body p {
  color: #262626;
  line-height: 1.5;
}

.message-reply {
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid #e0e0e0;
}

.message-reply small {
  color: #4caf50;
}

.empty-state {
  text-align: center;
  color: #999;
  padding: 2rem;
  font-style: italic;
}