base.scss

// stylelint-disable selector-max-type, selector-no-qualifying-type, primer/typography
* {
  box-sizing: border-box;
}

input,
select,
textarea,
button {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
}

body {
  font-family: $body-font;
  font-size: var(--body-font-size, $body-font-size);
  line-height: $body-line-height;
  color: var(--fgColor-default, var(--color-fg-default));
  background-color: var(--bgColor-default, var(--color-canvas-default));
}

a {
  color: var(--fgColor-accent, var(--color-accent-fg));
  text-decoration: none;

  &:hover {
    text-decoration: underline;
  }
}

b,
strong {
  font-weight: $font-weight-bold;
}

fieldset {
  padding: 0;
  margin: 0;
  border: 0;
}

label {
  font-weight: $font-weight-bold;
}

// Custom styling for HTML5 validation bubbles (WebKit only)
::placeholder {
  color: var(--fgColor-muted, var(--color-fg-subtle));
  opacity: 1; // override opacity in normalize.css
}

// Horizontal lines
//
// TODO-MDO: Remove `.rule` from everywhere and replace with `<hr>`s
hr,
.rule {
  height: 0;
  // stylelint-disable-next-line primer/spacing
  margin: 15px 0;
  overflow: hidden;
  background: transparent;
  border: 0;
  border-bottom: $border-width $border-style var(--borderColor-muted, var(--color-border-muted));

  @include clearfix();
}

//
// Remove most spacing between table cells.
//

table {
  border-spacing: 0;
  border-collapse: collapse;
}

td,
th {
  padding: 0;
}

button {
  cursor: pointer;
  // Remove border radius added by Chrome macOS
  border-radius: 0;
}

// increase the selector specificity for [hidden]
// so that it always overrides utility classes (.d-block, etc.)
[hidden][hidden] {
  display: none !important;
}

details {
  summary {
    cursor: pointer;
  }

  &:not([open]) {
    // Set details content hidden by default for browsers that don't do this
    > *:not(summary) {
      display: none;
    }
  }
}

// global focus styles

a,
button,
[role='button'],
input[type='radio'],
input[type='checkbox'] {
  // fallback :focus state
  &:focus {
    @include focusOutline;

    // remove fallback :focus if :focus-visible is supported
    &:not(:focus-visible) {
      outline: solid 1px transparent;
    }
  }

  // default focus state
  &:focus-visible {
    @include focusOutline;
  }
}

a:not([class]),
input[type='radio'],
input[type='checkbox'] {
  &:focus,
  &:focus-visible {
    outline-offset: 0;
  }
}

// for handling focus conditionally
.focus {
  @include focusBoxShadowInset;
}

// Windows High Contrast mode
@media (forced-colors: active) {
  *:focus,
  *:focus-visible {
    outline: solid 1px transparent;
  }

  input:not([type='radio'], [type='checkbox']),
  textarea,
  select {
    &:focus,
    &:focus-visible {
      outline-offset: 2px;
    }
  }
}