body {
  font-family: Arial, sans-serif;
  background-color: #f4f4f9;
  margin: 0;
  padding: 20px;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  background: white;
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

h1, h2 {
  color: #333;
}

button, a {
  padding: 10px 20px;
  background: #007bff;
  color: white;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  text-decoration: none;
}

button:hover, a:hover {
  background: #0056b3;
}

#metrics p {
  font-size: 18px;
  margin: 10px 0;
}

#contacts-list, #chat-view {
  border: 1px solid #ddd;
  border-radius: 5px;
  padding: 10px;
  max-height: 400px;
  overflow-y: auto;
}

.contact {
  padding: 10px;
  border-bottom: 1px solid #eee;
  cursor: pointer;
}

.contact:hover {
  background: #f9f9f9;
}

.message {
  padding: 10px;
  margin: 5px 0;
  border-radius: 15px;
  max-width: 70%;
}

.sent {
  background: #dcf8c6;
  align-self: flex-end;
  margin-left: auto;
}

.received {
  background: #ffffff;
  border: 1px solid #ddd;
  align-self: flex-start;
}

form {
  display: flex;
  flex-direction: column;
  max-width: 300px;
  margin: 0 auto;
}

label {
  margin-top: 10px;
}

input {
  padding: 10px;
  margin: 5px 0;
  border: 1px solid #ddd;
  border-radius: 5px;
}