:root {
  --bg: #222222;
  --fg: #e9e9e9;
}

html {
  box-sizing: border-box;
}

*,
*::before,
*::after {
  box-sizing: inherit;
}

body {
  background-color: var(--bg);
  margin: 0;
}

main {
  color: var(--fg);
  font-family: sans;
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem;
}

h1 > a,
h1 > a:visited {
  color: var(--fg);
}

a {
  color: cornflowerblue;
}

a:visited {
  color: mediumorchid;
}

label {
  display: inline-block;
  margin-right: 0.25em;
  margin-bottom: 0.5em;
}

input,
select,
textarea,
.button {
  display: inline-block;
  background-color: var(--bg);
  color: var(--fg);
  padding: 0.5rem;
  border: 2px solid var(--fg);
  border-radius: 5px;
  margin-bottom: 1rem;
  max-width: calc(100vw - 2rem);
}

*.hidden {
  display: none;
}

input[type="checkbox"] {
  margin-bottom: 1.5rem;
}

.button {
  cursor: pointer;
  font-size: 1rem;
}

a.button {
  text-decoration: none;
}

a.button:visited {
  color: var(--fg);
}

.button:hover {
  background-color: #444444;
}

.button.main {
  background-color: #007600;
}

.button.main:hover {
  background-color: forestgreen;
}

.usage {
  margin-top: 2em;
  overflow: auto;
}