KNACSS/sass/base/_reset-base.scss

/* ----------------------------- */
/* ==Reset (base)                */
/* ----------------------------- */

/*
 * 1. Switch to border-box model for all elements
 * 2. Avoid min-width: auto on flex and grid items
 */

*,
*::before,
*::after {
  box-sizing: border-box;
  /* 1 */
  min-width: 0;
  /* 2 */
}

/*
 * 1. Remove the grey highlight on links in iOS 
 * 2. Prevent orientation font changes in iOS
 * 3. Breaks words to prevent overflow in all browsers
 */

html {
  font-size: $font-size-html;
  -webkit-tap-highlight-color: transparent;
  /* 1 */
  -webkit-text-size-adjust: 100%;
  /* 2 */
  overflow-wrap: break-word;
  /* 3 */
}

body {
  margin: 0;
  font-family: $font-family-base;
  font-size: $font-size-base;
  line-height: $line-height-base;
  background-color: $body-bg;
  color: $body-color;
}

/*
 * Headings
 */

h1,
.h1-like,
h2,
.h2-like,
h3,
.h3-like,
h4,
.h4-like,
h5,
.h5-like,
h6,
.h6-like {
  color: $gray-900;
}

/*
 * Links
 */

a {
  color: $gray-600;
  text-decoration: $link-decoration;
}

a:focus,
a:hover,
a:active {
  color: $gray-900;
  text-decoration: $link-decoration-hover;
}

/**
 * 1. Remove the bottom border in Chrome 57-
 * 2. Add the correct text decoration in Chrome, Edge, IE, Opera, and Safari.
 */

abbr[title] {
  border-bottom: none;
  /* 1 */
  text-decoration: underline;
  /* 2 */
  text-decoration: underline dotted;
  /* 2 */
}

/*
 * Vertical rythm
 */

h1,
.h1-like,
h2,
.h2-like {
  margin-top: 0;
  margin-bottom: $spacer-medium;
}

p,
address,
ol,
ul,
dl,
blockquote,
pre,
h3,
.h3-like,
h4,
.h4-like,
h5,
.h5-like,
h6,
.h6-like,
dt,
dd {
  margin-top: 0;
  margin-bottom: $spacer-small;
}

/*
 * Nested elements
 */

ol ol,
ol ul,
ul ol,
ul ul,
li ul,
li ol,
nav ul,
nav ol,
li p,
li .p-like {
  margin-top: 0;
  margin-bottom: 0;
}

/*
 * Lists
 */

ul,
ol {
  padding-left: $spacer-medium;
}

nav ul,
nav ol {
  list-style: none;
  padding: 0;
}

/*
 * Embed content
 */

audio,
canvas,
iframe,
img,
svg,
video {
  vertical-align: middle;
}

img,
table,
td,
blockquote,
pre,
code,
input,
textarea,
select,
video,
svg,
iframe {
  max-width: 100%;
}

iframe,
img,
input,
select,
textarea {
  height: auto;
}

img {
  border-style: none;
}

/**
 * Remove the border on iframes in all browsers
 */

iframe {
  border-style: none;
}

/*
 * Fill color matching to text color
 */

svg:not([fill]) {
  fill: currentColor;
}

/*
 * Hide the overflow in IE
 */

svg:not(:root) {
  overflow: hidden;
}

/*
 * Tables
 */

table {
  border-collapse: collapse;
}

/*
 * Rulers
 */

hr {
  box-sizing: content-box;
  height: 0;
  overflow: visible;
  border: 0;
  border-top: 1px solid;
  margin: $spacer-medium 0;
  clear: both;
  color: inherit;
}

/*
 * table styles
 */

table {
  width: 100%;
  max-width: 100%;
  table-layout: fixed;
  border-collapse: collapse;
  vertical-align: top;
  margin-bottom: $spacer-medium;
}