* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f2f2f2;
}

.chat-app {
  width: 500px;
  height: 600px;
  margin: 40px auto;
  background: white;
  border: 1px solid #ccc;
  border-radius: 8px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.chat-header {
  text-align: center;
  padding: 10px;
  border-bottom: 1px solid #ccc;
}

.chat-header h1 {
  margin: 0;
  font-size: 24px;
}

.messages {
  flex: 1;
  padding: 20px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

.message {
  max-width: 70%;
  padding: 10px;
  margin-bottom: 15px;
  border: 1px solid #ccc;
  border-radius: 8px;
  word-wrap: break-word;
}

.received {
  align-self: flex-start;
}

.sent {
  align-self: flex-end;
}

.reactions {
  margin-top: 8px;
}

.reactions button {
  border: none;
  background: none;
  cursor: pointer;
  padding: 3px 6px;
}

.reactions button:hover {
  background: #f0f0f0;
  border-radius: 4px;
}

.chat-input {
  display: flex;
  padding: 10px;
  border-top: 1px solid #ccc;
}

#message-input {
  flex: 1;
  padding: 10px;
  border: 1px solid #ccc;
  border-radius: 4px;
}

#send-button {
  margin-left: 8px;
  padding: 10px 20px;
  border: 1px solid #ccc;
  border-radius: 4px;
  background: white;
  cursor: pointer;
}

#send-button:hover {
  background: #f0f0f0;
}