*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: sans-serif;
  font-size: 1rem;
  line-height: 1.6;
  max-width: 680px;
  margin: 0 auto;
  padding: 1.5rem 1rem;
  background: #fff;
  color: #111;
}

header {
  border-bottom: 2px solid #111;
  padding-bottom: 0.5rem;
  margin-bottom: 1.5rem;
}

h1 {
  font-size: 1.8rem;
}

h2 {
  font-size: 1.2rem;
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

h3 {
  font-weight: bold;
  font-size: 1rem;
  margin-top: 1rem;
  margin-bottom: 0.5rem;
}

p {
  margin-bottom: 0.75rem;
}

ul {
  padding-left: 1.25rem;
  margin-bottom: 0.75rem;
}

li {
  margin-bottom: 0.25rem;
}

form {
  margin-top: 0.75rem;
}

form div {
  margin-bottom: 0.75rem;
}

label {
  display: block;
  margin-bottom: 0.25rem;
  font-weight: bold;
}

input[type="text"],
input[type="email"],
textarea {
  width: 100%;
  padding: 0.4rem;
  font-family: sans-serif;
  font-size: 1rem;
  border: 1px solid #888;
}

textarea {
  resize: vertical;
}

button[type="submit"] {
  padding: 0.4rem 1rem;
  font-family: sans-serif;
  font-size: 1rem;
  cursor: pointer;
}

footer {
  border-top: 1px solid #ccc;
  margin-top: 2rem;
  padding-top: 0.75rem;
  font-size: 0.85rem;
  color: #555;
}