* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f3f4f6;
  color: #111827;
}

.chat-shell {
  max-width: 760px;
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: #fff;
}

.chat-header {
  padding: 16px;
  border-bottom: 1px solid #e5e7eb;
}

.chat-header h1 {
  margin: 0 0 6px;
  font-size: 20px;
}

.chat-header p {
  margin: 0;
  font-size: 13px;
  color: #6b7280;
}

.messages {
  flex: 1;
  padding: 16px;
  overflow-y: auto;
}

.msg {
  max-width: 80%;
  margin: 0 0 10px;
  padding: 10px 12px;
  border-radius: 14px;
  background: #e5e7eb;
}

.msg.self {
  margin-left: auto;
  background: #bfdbfe;
}

.composer {
  border-top: 1px solid #e5e7eb;
  padding: 12px;
}

.row {
  display: flex;
  gap: 8px;
  align-items: center;
  margin-bottom: 8px;
}

#messageInput {
  flex: 1;
  border: 1px solid #d1d5db;
  border-radius: 10px;
  padding: 10px 12px;
}

button {
  border: 1px solid #d1d5db;
  background: #fff;
  border-radius: 10px;
  padding: 10px 12px;
  cursor: pointer;
}

.emoji-panel {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.emoji-panel.hidden {
  display: none;
}

@media (max-width: 768px) {
  .chat-shell {
    max-width: 100%;
  }
}