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

body {
  min-height: 100vh;
  font-family: Arial, sans-serif;
}

.container {
  max-width: 100%;
  padding-inline: 12px;
  padding-block: 12px;
  margin-inline: auto;
}

/*
    Header
*/

header {
  padding: 1rem 0;
}

header h1.title {
  text-align: center;
}

/*
    Main
*/

main .display textarea {
  width: 100%;
  padding: 8px;
  resize: vertical;
}

main .container > * {
  margin-block-end: 1rem;
}

/*
    Footer
*/

footer {
  padding: 1rem;
}

footer p {
  text-align: center;
}

/*
  Button
*/

.btn {
  display: inline-block;
  padding: 8px 16px;
  border-radius: 4px;

  font-weight: 400;
  font-size: 15px;

  cursor: pointer;
  transition: 0.15s ease-in-out;
}

@media screen and (min-width: 768px) {
  .container {
    max-width: 600px;
  }
}

@media screen and (min-width: 992px) {
  .container {
    max-width: 800px;
  }
}