body {
  font-family: 'Segoe UI', sans-serif;
  background-color: #f4f4f4;
  margin: 0;
  padding: 0;
}

header {
  display: flex;
  align-items: center;
  background-color: #222;
  color: #fff;
  padding: 10px 20px;
}

#logo {
  height: 40px;
  margin-right: 15px;
}

h1 {
  margin: 0;
  font-size: 1.8em;
}

.container {
  max-width: 800px;
  margin: 20px auto;
  background-color: #fff;
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

input, textarea {
  width: 100%;
  padding: 10px;
  margin-top: 8px;
  margin-bottom: 16px;
  border: 1px solid #ccc;
  border-radius: 4px;
  box-sizing: border-box;
}

button {
  background-color: #0078d4;
  color: white;
  padding: 10px 16px;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 14px;
}

button:hover {
  background-color: #005fa3;
}

.account {
  background-color: #f9f9f9;
  border: 1px solid #ddd;
  border-radius: 5px;
  padding: 15px;
  margin-top: 20px;
}

.mailList ul {
  list-style: none;
  padding-left: 0;
}

.mailList li {
  padding: 5px 0;
  border-bottom: 1px solid #eee;
}

@media (max-width: 600px) {
  header, .container {
    padding: 10px;
  }
  h1 {
    font-size: 1.4em;
  }
  button {
    width: 100%;
  }
}