* {
  box-sizing: border-box;
}

body {
  font-family: sans-serif;
  background-color: #223;
  color: #fff;
  max-width: 720px;
  padding: 1rem;
}

img {
  max-width: 5rem;
}

h1 {
  font-size: 2rem;
  font-family: sans-serif;
  margin-top: 1rem;
}

a, a:visited {
  color: #bdf;
}

input[type="text"], textarea {
  background-color: #445;
  color: #fff;
  border: none;
  padding: 0.25rem 0.3rem;
  width: 20rem;
}

input[type="text"]::placeholder, textarea::placeholder {
  color: #aaa;
}

input[type="text"]:focus, textarea:focus {
  outline: none;
  border: 2px solid #aaa;
}

input[type="text"] {
  height: 2rem;
}
textarea {
  font-family: sans-serif;
  height: 4rem;
  width: 30rem;
  resize: none;
}

button {
  background-color: #457;
  color: #fff;
  padding: 0.25rem 0.5rem;
  border: 1px solid #aaa;
  cursor: pointer;
}

code {
  font-size: 1.5rem;
}

.error:not(:empty) {
  background-color: #744;
  color: #faa;
  padding: 0.5rem 0.625rem;
  width: max-content;
}