silverstripe-framework/admin/scss/_reset.scss

// Based on [Eric Meyer's reset 2.0](http://meyerweb.com/eric/tools/css/reset/index.html)
// Global reset rules.
// For more specific resets, use the reset mixins provided below
@mixin global-reset {
  html, body, div, span, applet, object, iframe,
  h1, h2, h3, h4, h5, h6, p, blockquote, pre,
  a, abbr, acronym, address, big, cite, code,
  del, dfn, em, img, ins, kbd, q, s, samp,
  small, strike, strong, sub, sup, tt, var,
  b, u, i, center,
  dl, dt, dd, ol, ul, li,
  fieldset, form, label, legend,
  table, caption, tbody, tfoot, thead, tr, th, td,
  article, aside, canvas, details, embed, 
  figure, figcaption, footer, header, hgroup, 
  menu, nav, output, ruby, section, summary,
  time, mark, audio, video {
    @include reset-box-model;
    @include reset-font; }
  // Unlike Eric's original reset, we reset the html element to be compatible
  // with the vertical rhythm mixins.
  html {
    @include reset-body; }
  ol, ul {
    @include reset-list-style; }
  table {
    @include reset-table; }
  caption, th, td {
    @include reset-table-cell; }
  q, blockquote {
    @include reset-quotation; }
  a img {
    @include reset-image-anchor-border; }
  @include reset-html5; }

// Reset all elements within some selector scope. To reset the selector itself,
// mixin the appropriate reset mixin for that element type as well. This could be
// useful if you want to style a part of your page in a dramatically different way.
@mixin nested-reset {
  div, span, applet, object, iframe,
  h1, h2, h3, h4, h5, h6, p, blockquote, pre,
  a, abbr, acronym, address, big, cite, code,
  del, dfn, em, img, ins, kbd, q, s, samp,
  small, strike, strong, sub, sup, tt, var,
  b, u, i, center,
  dl, dt, dd, ol, ul, li,
  fieldset, form, label, legend,
  table, caption, tbody, tfoot, thead, tr, th, td,
  article, aside, canvas, details, embed, 
  figure, figcaption, footer, header, hgroup, 
  menu, nav, output, ruby, section, summary,
  time, mark, audio, video {
    @include reset-box-model;
    @include reset-font; }
  table {
    @include reset-table; }
  caption, th, td {
    @include reset-table-cell; }
  q, blockquote {
    @include reset-quotation; }
  a img {
    @include reset-image-anchor-border; } }

// Reset the box model measurements.
@mixin reset-box-model {
  margin: 0;
  padding: 0;
  border: 0; }

// Reset the font and vertical alignment.
@mixin reset-font {
  vertical-align: baseline; }

// Resets the outline when focus.
// For accessibility you need to apply some styling in its place.
@mixin reset-focus {
  outline: 0; }

// Reset a body element.
@mixin reset-body {
  line-height: 1; }

// Reset the list style of an element.
@mixin reset-list-style {
  list-style: none; }

// Reset a table
@mixin reset-table {
  border-collapse: collapse;
  border-spacing: 0; }

// Reset a table cell (`th`, `td`)
@mixin reset-table-cell {
  text-align: left;
  font-weight: normal;
  vertical-align: middle; }

// Reset a quotation (`q`, `blockquote`)
@mixin reset-quotation {
  quotes: none;
  &:before, &:after {
    content: ""; 
    content: none; } }

// Resets the border.
@mixin reset-image-anchor-border {
  border: none; }

// Unrecognized elements are displayed inline.
// This reset provides a basic reset for block html5 elements
// so they are rendered correctly in browsers that don't recognize them
// and reset in browsers that have default styles for them.
@mixin reset-html5 {
  #{elements-of-type(html5-block)} {
    display: block; } }

// Resets the display of inline and block elements to their default display
// according to their tag type. Elements that have a default display that varies across
// versions of html or browser are not handled here, but this covers the 90% use case.
// Usage Example:
//
//     // Turn off the display for both of these classes
//     .unregistered-only, .registered-only
//       display: none
//     // Now turn only one of them back on depending on some other context.
//     body.registered
//       +reset-display(".registered-only")
//     body.unregistered
//       +reset-display(".unregistered-only")
@mixin reset-display($selector: "", $important: false) {
  #{append-selector(elements-of-type("inline"), $selector)} {
    @if $important {
      display: inline !important; }
    @else {
      display: inline; } }
  #{append-selector(elements-of-type("block"), $selector)} {
    @if $important {
      display: block !important; }
    @else {
      display: block; } } }

@include global-reset;