body {
  font-family: Arial, sans-serif;
  background: #f5f5f5;
  color: #333;
  margin: 0;
  padding: 0;
  line-height: 1.6;
}

header, main, footer {
  max-width: 900px;
  margin: auto;
  background: white;
  padding: 20px;
  margin-top: 10px;
  border-radius: 10px;
}

h1, h2 {
  color: #2a4f7c;
}

input[type="text"],
input[type="email"],
textarea {
  width: 100%;
  margin-bottom: 10px;
  padding: 8px;
}

input[type="submit"],
button {
  padding: 10px 15px;
  background-color: #2a4f7c;
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
}

.dark-mode {
  background-color: #1a1a1a;
  color: #eee;
}

.dark-mode input,
.dark-mode textarea {
  background: #333;
  color: #eee;
}