:root {
  --bg: #ffffff;
  --colour: #000000;
  --shadow: rgba(0, 0, 0, 0.2);
  --error: #ff0000;
  --offset-bg: #dddddd;
  --offset-colour: #000000;
  --offset-bg--active: #eeeeee;
  --offset-colour--active: #000000;
  --gutter: 2rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111111;
    --colour: #ffffff;
    --shadow: rgba(255, 255, 255, 0.2);
    --error: #ff6666;
    --offset-bg: #666666;
    --offset-colour: #ffffff;
    --offset-bg--active: #777777;
    --offset-colour--active: #ffffff;
  }
}
* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0 0 2rem 0;
  color-scheme: dark light;
  font-family: "Arial", "Helvetica", sans-serif;
  background-color: var(--bg);
  color: var(--colour);
}

.no-transitions * {
  transition: none !important;
}

button {
  all: unset;
}

summary {
  cursor: pointer;
}
summary :where(h1, h2, h3, h4, h5, h6) {
  display: inline-block;
}
details:not([open]) summary :where(h1, h2, h3, h4, h5, h6) {
  margin: 0;
}

.content {
  margin: 1rem auto;
  padding-inline: var(--gutter);
  max-width: 80ch;
}
.content h1,
.content h2,
.content h3,
.content h4,
.content h5,
.content h6 {
  margin-top: 0;
}
.content section + section {
  margin-top: 2rem;
  border-top: 1px solid var(--colour);
  padding-top: 2rem;
}

.typeguardian {
  display: grid;
  gap: 2rem;
  padding: 1rem var(--gutter);
  min-height: calc(100svh - 5rem);
  grid-template-areas: "header" "controls" "input" "output";
  grid-template-rows: auto auto 1fr 1fr;
}
@media (width >= 1024px) {
  .typeguardian {
    grid-template-areas: "header header" "controls controls" "input output";
    grid-template-columns: repeat(2, 1fr);
    grid-template-rows: auto auto 1fr;
  }
}

.typeguardian__header {
  grid-area: header;
}

.typeguardian__controls {
  grid-area: controls;
}

.typeguardian__input {
  grid-area: input;
}

.typeguardian__output {
  grid-area: output;
}

.no-js .typeguardian__controls,
.no-js .typeguardian__input,
.no-js .typeguardian__output {
  display: none;
}

.typeguardian__no-js {
  grid-row: 2/5;
  align-self: center;
  justify-self: center;
  font-size: 1.2rem;
  color: var(--error);
}
@media (width >= 1024px) {
  .typeguardian__no-js {
    grid-column: 1/3;
    grid-row: 2/4;
  }
}

.typeguardian__title {
  display: inline-block;
  margin: 0;
  font-size: 2rem;
}
@media (width >= 768px) {
  .typeguardian__title {
    font-size: 3rem;
  }
}

.typeguardian__controls__actions {
  display: flex;
  gap: 1rem;
}

.typeguardian__button {
  padding: 0.5rem 0.7rem;
  cursor: pointer;
  border-radius: 0.2rem;
  background: var(--offset-bg);
  color: var(--offset-colour);
  transition: background-color 0.3s ease-in-out, color 0.3s ease-in-out;
}
.typeguardian__button:hover, .typeguardian__button:focus {
  background: var(--offset-bg--active);
  color: var(--offset-colour--active);
}

.typeguardian__controls__options {
  margin-top: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.typeguardian__input,
.typeguardian__output {
  padding: 0.5rem;
  min-height: 100%;
  resize: vertical;
}
.typeguardian__input.has-error,
.typeguardian__output.has-error {
  border-color: var(--error);
}

.toast__container {
  position: fixed;
  bottom: 1rem;
  right: var(--gutter);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.toast {
  padding: 0.5rem;
  background: var(--bg);
  border: 1px solid currentColor;
  box-shadow: 0 0 0.5rem var(--shadow);
}