リセットCSS は何を使う？ おすすめ８選（コピペも可能！）

Web開発でブラウザごとの表示の違いをリセットしてくれる リセットCSS というものがあります。
しかし、何を使っていいのかと感じている人もいると思います。

今回はこの リセットCSS について、この記事にまとめました。

リセットCSSが必要な理由

リセットCSS は、ブラウザごとの表示の違いをリセットしてくれるCSSファイルです。

ブラウザにはEdgeやChrome、Safariなど、様々なものがあります。
しかし、そういったブラウザの違いを意識せずにサイトを作ると、ブラウザによって異なる見た目になってしまうため、レイアウトが崩れてしまったりといったことが起こります。

そういったブラウザによる見え方の違いを揃えてくれるのがリセットCSSです。
これを使うことによって、ブラウザごとの違いを意識せずにコーディングができ、サイト制作が楽になります。

Eric Meyer’s “Reset CSS” 2.0

リセットCSS でもっとも人気が高いのが、 Eric Meyer’s “Reset CSS” 2.0 です。
Eric Meyer’s “Reset CSS” 2.0

「Eric Meyer’s “Reset CSS” 2.0」は、リセットCSSの先駆者の一人、Eric Meyerさんによって作られたリセットCSSです。
2008年2月にv1.0が作られ、いまも断トツの一位となっています。

以下がそのCSSです。

/* http://meyerweb.com/eric/tools/css/reset/ 
   v2.0 | 20110126
   License: none (public domain)
*/

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 {
	margin: 0;
	padding: 0;
	border: 0;
	font-size: 100%;
	font: inherit;
	vertical-align: baseline;
}
/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure, 
footer, header, hgroup, menu, nav, section {
	display: block;
}
body {
	line-height: 1;
}
ol, ul {
	list-style: none;
}
blockquote, q {
	quotes: none;
}
blockquote:before, blockquote:after,
q:before, q:after {
	content: '';
	content: none;
}
table {
	border-collapse: collapse;
	border-spacing: 0;
}

HTML5 Doctor CSS Reset

リセットCSSで二番目に人気なのが、「HTML5 Doctor CSS Reset」です。
HTML5 Doctor CSS Reset

HTML5 Doctor CSS Reset は、先ほど紹介した Eric Meyer’s CSS reset を HTML5 で使うために修正したものだそうです。
HTML5で非推奨になったタグの削除や、新しいHTML5の要素の追加などがされています。

/* 
html5doctor.com Reset Stylesheet
v1.6.1
Last Updated: 2010-09-17
Author: Richard Clark - http://richclarkdesign.com 
Twitter: @rich_clark
*/

html, body, div, span, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
abbr, address, cite, code,
del, dfn, em, img, ins, kbd, q, samp,
small, strong, sub, sup, var,
b, i,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, figcaption, figure, 
footer, header, hgroup, menu, nav, section, summary,
time, mark, audio, video {
    margin:0;
    padding:0;
    border:0;
    outline:0;
    font-size:100%;
    vertical-align:baseline;
    background:transparent;
}

body {
    line-height:1;
}

article,aside,details,figcaption,figure,
footer,header,hgroup,menu,nav,section { 
    display:block;
}

nav ul {
    list-style:none;
}

blockquote, q {
    quotes:none;
}

blockquote:before, blockquote:after,
q:before, q:after {
    content:'';
    content:none;
}

a {
    margin:0;
    padding:0;
    font-size:100%;
    vertical-align:baseline;
    background:transparent;
}

/* change colours to suit your needs */
ins {
    background-color:#ff9;
    color:#000;
    text-decoration:none;
}

/* change colours to suit your needs */
mark {
    background-color:#ff9;
    color:#000; 
    font-style:italic;
    font-weight:bold;
}

del {
    text-decoration: line-through;
}

abbr[title], dfn[title] {
    border-bottom:1px dotted;
    cursor:help;
}

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

/* change border colour to suit your needs */
hr {
    display:block;
    height:1px;
    border:0;   
    border-top:1px solid #cccccc;
    margin:1em 0;
    padding:0;
}

input, select {
    vertical-align:middle;
}

Yahoo! (YUI 3) Reset CSS

Yahoo! (YUI 3) Reset CSS は、 Yahoo! が開発したものです。
Yahoo! (YUI 3) Reset CSS

/*
YUI 3.18.1 (build f7e7bcb)
Copyright 2014 Yahoo! Inc. All rights reserved.
Licensed under the BSD License.
http://yuilibrary.com/license/
*/

/*
	TODO will need to remove settings on HTML since we can't namespace it.
	TODO with the prefix, should I group by selector or property for weight savings?
*/
html{
	color:#000;
	background:#FFF;
}
/*
	TODO remove settings on BODY since we can't namespace it.
*/
/*
	TODO test putting a class on HEAD.
		- Fails on FF.
*/
body,
div,
dl,
dt,
dd,
ul,
ol,
li,
h1,
h2,
h3,
h4,
h5,
h6,
pre,
code,
form,
fieldset,
legend,
input,
textarea,
p,
blockquote,
th,
td {
	margin:0;
	padding:0;
}
table {
	border-collapse:collapse;
	border-spacing:0;
}
fieldset,
img {
	border:0;
}
/*
	TODO think about hanlding inheritence differently, maybe letting IE6 fail a bit...
*/
address,
caption,
cite,
code,
dfn,
em,
strong,
th,
var {
	font-style:normal;
	font-weight:normal;
}

ol,
ul {
	list-style:none;
}

caption,
th {
	text-align:left;
}
h1,
h2,
h3,
h4,
h5,
h6 {
	font-size:100%;
	font-weight:normal;
}
q:before,
q:after {
	content:'';
}
abbr,
acronym {
	border:0;
	font-variant:normal;
}
/* to preserve line-height and selector appearance */
sup {
	vertical-align:text-top;
}
sub {
	vertical-align:text-bottom;
}
input,
textarea,
select {
	font-family:inherit;
	font-size:inherit;
	font-weight:inherit;
	*font-size:100%; /*to enable resizing for IE*/
}
/*because legend doesn't inherit in IE */
legend {
	color:#000;
}

/* YUI CSS Detection Stamp */
#yui3-css-stamp.cssreset { display: none; }

Universal Selector ‘*’ Reset

Universal Selector ‘*’ Reset は、ユニバーサルセレクタを使って、全ての要素に margin: 0, padding: 0 を指定する、かなりシンプルなものです。

* {
	margin: 0;
	padding: 0;
}

Normalize.css

Normalize.css は、 リセットCSS とは少し違い、デフォルトのスタイルはあえて残しつつ、ブラウザごとの違いを修正するという考え方で作られているようです。
Normalize.css

/*! normalize.css v8.0.1 | MIT License | github.com/necolas/normalize.css */

/* Document
   ========================================================================== */

/**
 * 1. Correct the line height in all browsers.
 * 2. Prevent adjustments of font size after orientation changes in iOS.
 */

html {
  line-height: 1.15; /* 1 */
  -webkit-text-size-adjust: 100%; /* 2 */
}

/* Sections
   ========================================================================== */

/**
 * Remove the margin in all browsers.
 */

body {
  margin: 0;
}

/**
 * Render the `main` element consistently in IE.
 */

main {
  display: block;
}

/**
 * Correct the font size and margin on `h1` elements within `section` and
 * `article` contexts in Chrome, Firefox, and Safari.
 */

h1 {
  font-size: 2em;
  margin: 0.67em 0;
}

/* Grouping content
   ========================================================================== */

/**
 * 1. Add the correct box sizing in Firefox.
 * 2. Show the overflow in Edge and IE.
 */

hr {
  box-sizing: content-box; /* 1 */
  height: 0; /* 1 */
  overflow: visible; /* 2 */
}

/**
 * 1. Correct the inheritance and scaling of font size in all browsers.
 * 2. Correct the odd `em` font sizing in all browsers.
 */

pre {
  font-family: monospace, monospace; /* 1 */
  font-size: 1em; /* 2 */
}

/* Text-level semantics
   ========================================================================== */

/**
 * Remove the gray background on active links in IE 10.
 */

a {
  background-color: transparent;
}

/**
 * 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 */
}

/**
 * Add the correct font weight in Chrome, Edge, and Safari.
 */

b,
strong {
  font-weight: bolder;
}

/**
 * 1. Correct the inheritance and scaling of font size in all browsers.
 * 2. Correct the odd `em` font sizing in all browsers.
 */

code,
kbd,
samp {
  font-family: monospace, monospace; /* 1 */
  font-size: 1em; /* 2 */
}

/**
 * Add the correct font size in all browsers.
 */

small {
  font-size: 80%;
}

/**
 * Prevent `sub` and `sup` elements from affecting the line height in
 * all browsers.
 */

sub,
sup {
  font-size: 75%;
  line-height: 0;
  position: relative;
  vertical-align: baseline;
}

sub {
  bottom: -0.25em;
}

sup {
  top: -0.5em;
}

/* Embedded content
   ========================================================================== */

/**
 * Remove the border on images inside links in IE 10.
 */

img {
  border-style: none;
}

/* Forms
   ========================================================================== */

/**
 * 1. Change the font styles in all browsers.
 * 2. Remove the margin in Firefox and Safari.
 */

button,
input,
optgroup,
select,
textarea {
  font-family: inherit; /* 1 */
  font-size: 100%; /* 1 */
  line-height: 1.15; /* 1 */
  margin: 0; /* 2 */
}

/**
 * Show the overflow in IE.
 * 1. Show the overflow in Edge.
 */

button,
input { /* 1 */
  overflow: visible;
}

/**
 * Remove the inheritance of text transform in Edge, Firefox, and IE.
 * 1. Remove the inheritance of text transform in Firefox.
 */

button,
select { /* 1 */
  text-transform: none;
}

/**
 * Correct the inability to style clickable types in iOS and Safari.
 */

button,
[type="button"],
[type="reset"],
[type="submit"] {
  -webkit-appearance: button;
}

/**
 * Remove the inner border and padding in Firefox.
 */

button::-moz-focus-inner,
[type="button"]::-moz-focus-inner,
[type="reset"]::-moz-focus-inner,
[type="submit"]::-moz-focus-inner {
  border-style: none;
  padding: 0;
}

/**
 * Restore the focus styles unset by the previous rule.
 */

button:-moz-focusring,
[type="button"]:-moz-focusring,
[type="reset"]:-moz-focusring,
[type="submit"]:-moz-focusring {
  outline: 1px dotted ButtonText;
}

/**
 * Correct the padding in Firefox.
 */

fieldset {
  padding: 0.35em 0.75em 0.625em;
}

/**
 * 1. Correct the text wrapping in Edge and IE.
 * 2. Correct the color inheritance from `fieldset` elements in IE.
 * 3. Remove the padding so developers are not caught out when they zero out
 *    `fieldset` elements in all browsers.
 */

legend {
  box-sizing: border-box; /* 1 */
  color: inherit; /* 2 */
  display: table; /* 1 */
  max-width: 100%; /* 1 */
  padding: 0; /* 3 */
  white-space: normal; /* 1 */
}

/**
 * Add the correct vertical alignment in Chrome, Firefox, and Opera.
 */

progress {
  vertical-align: baseline;
}

/**
 * Remove the default vertical scrollbar in IE 10+.
 */

textarea {
  overflow: auto;
}

/**
 * 1. Add the correct box sizing in IE 10.
 * 2. Remove the padding in IE 10.
 */

[type="checkbox"],
[type="radio"] {
  box-sizing: border-box; /* 1 */
  padding: 0; /* 2 */
}

/**
 * Correct the cursor style of increment and decrement buttons in Chrome.
 */

[type="number"]::-webkit-inner-spin-button,
[type="number"]::-webkit-outer-spin-button {
  height: auto;
}

/**
 * 1. Correct the odd appearance in Chrome and Safari.
 * 2. Correct the outline style in Safari.
 */

[type="search"] {
  -webkit-appearance: textfield; /* 1 */
  outline-offset: -2px; /* 2 */
}

/**
 * Remove the inner padding in Chrome and Safari on macOS.
 */

[type="search"]::-webkit-search-decoration {
  -webkit-appearance: none;
}

/**
 * 1. Correct the inability to style clickable types in iOS and Safari.
 * 2. Change font properties to `inherit` in Safari.
 */

::-webkit-file-upload-button {
  -webkit-appearance: button; /* 1 */
  font: inherit; /* 2 */
}

/* Interactive
   ========================================================================== */

/*
 * Add the correct display in Edge, IE 10+, and Firefox.
 */

details {
  display: block;
}

/*
 * Add the correct display in all browsers.
 */

summary {
  display: list-item;
}

/* Misc
   ========================================================================== */

/**
 * Add the correct display in IE 10+.
 */

template {
  display: none;
}

/**
 * Add the correct display in IE 10.
 */

[hidden] {
  display: none;
}

ress.css

ress

以下のコマンドでダウンロードが可能です。

npm install --save ress

/*!
 * ress.css • v1.2.2
 * MIT License
 * github.com/filipelinhares/ress
 */

/* # =================================================================
   # Global selectors
   # ================================================================= */

html {
  box-sizing: border-box;
  overflow-y: scroll; /* All browsers without overlaying scrollbars */
  -webkit-text-size-adjust: 100%; /* iOS 8+ */
}

*,
::before,
::after {
  background-repeat: no-repeat; /* Set `background-repeat: no-repeat` to all elements */
  box-sizing: inherit;
}

::before,
::after {
  text-decoration: inherit; /* Inherit text-decoration and vertical align to ::before and ::after pseudo elements */
  vertical-align: inherit;
}

/* Remove margin, padding of all elements and set background-no-repeat as default */
* {
  padding: 0; /* Reset `padding` and `margin` of all elements */
  margin: 0;
}

/* # =================================================================
   # General elements
   # ================================================================= */

/* Add the correct display in iOS 4-7.*/
audio:not([controls]) {
  display: none;
  height: 0;
}

hr {
  overflow: visible; /* Show the overflow in Edge and IE */
}

/*
* Correct `block` display not defined for any HTML5 element in IE 8/9
* Correct `block` display not defined for `details` or `summary` in IE 10/11
* and Firefox
* Correct `block` display not defined for `main` in IE 11
*/
article,
aside,
details,
figcaption,
figure,
footer,
header,
main,
menu,
nav,
section,
summary {
  display: block;
}

summary {
  display: list-item; /* Add the correct display in all browsers */
}

small {
  font-size: 80%; /* Set font-size to 80% in `small` elements */
}

[hidden],
template {
  display: none; /* Add the correct display in IE */
}

abbr[title] {
  border-bottom: 1px dotted; /* Add a bordered underline effect in all browsers */
  text-decoration: none; /* Remove text decoration in Firefox 40+ */
}

a {
  background-color: transparent; /* Remove the gray background on active links in IE 10 */
  -webkit-text-decoration-skip: objects; /* Remove gaps in links underline in iOS 8+ and Safari 8+ */
}

a:active,
a:hover {
  outline-width: 0; /* Remove the outline when hovering in all browsers */
}

code,
kbd,
pre,
samp {
  font-family: monospace, monospace; /* Specify the font family of code elements */
}

b,
strong {
  font-weight: bolder; /* Correct style set to `bold` in Edge 12+, Safari 6.2+, and Chrome 18+ */
}

dfn {
  font-style: italic; /* Address styling not present in Safari and Chrome */
}

/* Address styling not present in IE 8/9 */
mark {
  background-color: #ff0;
  color: #000;
}

/* https://gist.github.com/unruthless/413930 */
sub,
sup {
  font-size: 75%;
  line-height: 0;
  position: relative;
  vertical-align: baseline;
}

sub {
  bottom: -0.25em;
}

sup {
  top: -0.5em;
}

/* # =================================================================
   # Forms
   # ================================================================= */

input {
  border-radius: 0;
}

/* Apply cursor pointer to button elements */
button,
[type="button"],
[type="reset"],
[type="submit"],
[role="button"] {
  cursor: pointer;
}

/* Replace pointer cursor in disabled elements */
[disabled] {
  cursor: default;
}

[type="number"] {
  width: auto; /* Firefox 36+ */
}

[type="search"] {
  -webkit-appearance: textfield; /* Safari 8+ */
}

[type="search"]::-webkit-search-cancel-button,
[type="search"]::-webkit-search-decoration {
  -webkit-appearance: none; /* Safari 8 */
}

textarea {
  overflow: auto; /* Internet Explorer 11+ */
  resize: vertical; /* Specify textarea resizability */
}

button,
input,
optgroup,
select,
textarea {
  font: inherit; /* Specify font inheritance of form elements */
}

optgroup {
  font-weight: bold; /* Restore the font weight unset by the previous rule. */
}

button {
  overflow: visible; /* Address `overflow` set to `hidden` in IE 8/9/10/11 */
}

/* Remove inner padding and border in Firefox 4+ */
button::-moz-focus-inner,
[type="button"]::-moz-focus-inner,
[type="reset"]::-moz-focus-inner,
[type="submit"]::-moz-focus-inner {
  border-style: 0;
  padding: 0;
}

/* Replace focus style removed in the border reset above */
button:-moz-focusring,
[type="button"]::-moz-focus-inner,
[type="reset"]::-moz-focus-inner,
[type="submit"]::-moz-focus-inner {
  outline: 1px dotted ButtonText;
}

button,
html [type="button"], /* Prevent a WebKit bug where (2) destroys native `audio` and `video`controls in Android 4 */
[type="reset"],
[type="submit"] {
  -webkit-appearance: button; /* Correct the inability to style clickable types in iOS */
}

button,
select {
  text-transform: none; /* Firefox 40+, Internet Explorer 11- */
}

/* Remove the default button styling in all browsers */
button,
input,
select,
textarea {
  background-color: transparent;
  border-style: none;
  color: inherit;
}

/* Style select like a standard input */
select {
  -moz-appearance: none; /* Firefox 36+ */
  -webkit-appearance: none; /* Chrome 41+ */
}

select::-ms-expand {
  display: none; /* Internet Explorer 11+ */
}

select::-ms-value {
  color: currentColor; /* Internet Explorer 11+ */
}

legend {
  border: 0; /* Correct `color` not being inherited in IE 8/9/10/11 */
  color: inherit; /* Correct the color inheritance from `fieldset` elements in IE */
  display: table; /* Correct the text wrapping in Edge and IE */
  max-width: 100%; /* Correct the text wrapping in Edge and IE */
  white-space: normal; /* Correct the text wrapping in Edge and IE */
}

::-webkit-file-upload-button {
  -webkit-appearance: button; /* Correct the inability to style clickable types in iOS and Safari */
  font: inherit; /* Change font properties to `inherit` in Chrome and Safari */
}

[type="search"] {
  -webkit-appearance: textfield; /* Correct the odd appearance in Chrome and Safari */
  outline-offset: -2px; /* Correct the outline style in Safari */
}

/* # =================================================================
   # Specify media element style
   # ================================================================= */

img {
  border-style: none; /* Remove border when inside `a` element in IE 8/9/10 */
}

/* Add the correct vertical alignment in Chrome, Firefox, and Opera */
progress {
  vertical-align: baseline;
}

svg:not(:root) {
  overflow: hidden; /* Internet Explorer 11- */
}

audio,
canvas,
progress,
video {
  display: inline-block; /* Internet Explorer 11+, Windows Phone 8.1+ */
}

/* # =================================================================
   # Accessibility
   # ================================================================= */

/* Hide content from screens but not screenreaders */
@media screen {
  [hidden~="screen"] {
    display: inherit;
  }
  [hidden~="screen"]:not(:active):not(:focus):not(:target) {
    position: absolute !important;
    clip: rect(0 0 0 0) !important;
  }
}

/* Specify the progress cursor of updating elements */
[aria-busy="true"] {
  cursor: progress;
}

/* Specify the pointer cursor of trigger elements */
[aria-controls] {
  cursor: pointer;
}

/* Specify the unstyled cursor of disabled, not-editable, or otherwise inoperable elements */
[aria-disabled] {
  cursor: default;
}

/* # =================================================================
   # Selection
   # ================================================================= */

/* Specify text selection background color and omit drop shadow */

::-moz-selection {
  background-color: #b3d4fc; /* Required when declaring ::selection */
  color: #000;
  text-shadow: none;
}

::selection {
  background-color: #b3d4fc; /* Required when declaring ::selection */
  color: #000;
  text-shadow: none;
}

ress.css

Reboot.css

Bootstrap

Reboot.cssはBootstrapが開発しているリセットCSSです。
GitHubのBootstrapのページの中からダウンロードできます。
Reboot.css

/*!
 * Bootstrap Reboot v4.3.1 (https://getbootstrap.com/)
 * Copyright 2011-2019 The Bootstrap Authors
 * Copyright 2011-2019 Twitter, Inc.
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 * Forked from Normalize.css, licensed MIT (https://github.com/necolas/normalize.css/blob/master/LICENSE.md)
 */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-family: sans-serif;
  line-height: 1.15;
  -webkit-text-size-adjust: 100%;
  -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
}

article, aside, figcaption, figure, footer, header, hgroup, main, nav, section {
  display: block;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #212529;
  text-align: left;
  background-color: #fff;
}

[tabindex="-1"]:focus {
  outline: 0 !important;
}

hr {
  box-sizing: content-box;
  height: 0;
  overflow: visible;
}

h1, h2, h3, h4, h5, h6 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

p {
  margin-top: 0;
  margin-bottom: 1rem;
}

abbr[title],
abbr[data-original-title] {
  text-decoration: underline;
  -webkit-text-decoration: underline dotted;
  text-decoration: underline dotted;
  cursor: help;
  border-bottom: 0;
  -webkit-text-decoration-skip-ink: none;
  text-decoration-skip-ink: none;
}

address {
  margin-bottom: 1rem;
  font-style: normal;
  line-height: inherit;
}

ol,
ul,
dl {
  margin-top: 0;
  margin-bottom: 1rem;
}

ol ol,
ul ul,
ol ul,
ul ol {
  margin-bottom: 0;
}

dt {
  font-weight: 700;
}

dd {
  margin-bottom: .5rem;
  margin-left: 0;
}

blockquote {
  margin: 0 0 1rem;
}

b,
strong {
  font-weight: bolder;
}

small {
  font-size: 80%;
}

sub,
sup {
  position: relative;
  font-size: 75%;
  line-height: 0;
  vertical-align: baseline;
}

sub {
  bottom: -.25em;
}

sup {
  top: -.5em;
}

a {
  color: #007bff;
  text-decoration: none;
  background-color: transparent;
}

a:hover {
  color: #0056b3;
  text-decoration: underline;
}

a:not([href]):not([tabindex]) {
  color: inherit;
  text-decoration: none;
}

a:not([href]):not([tabindex]):hover, a:not([href]):not([tabindex]):focus {
  color: inherit;
  text-decoration: none;
}

a:not([href]):not([tabindex]):focus {
  outline: 0;
}

pre,
code,
kbd,
samp {
  font-family: SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 1em;
}

pre {
  margin-top: 0;
  margin-bottom: 1rem;
  overflow: auto;
}

figure {
  margin: 0 0 1rem;
}

img {
  vertical-align: middle;
  border-style: none;
}

svg {
  overflow: hidden;
  vertical-align: middle;
}

table {
  border-collapse: collapse;
}

caption {
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
  color: #6c757d;
  text-align: left;
  caption-side: bottom;
}

th {
  text-align: inherit;
}

label {
  display: inline-block;
  margin-bottom: 0.5rem;
}

button {
  border-radius: 0;
}

button:focus {
  outline: 1px dotted;
  outline: 5px auto -webkit-focus-ring-color;
}

input,
button,
select,
optgroup,
textarea {
  margin: 0;
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
}

button,
input {
  overflow: visible;
}

button,
select {
  text-transform: none;
}

select {
  word-wrap: normal;
}

button,
[type="button"],
[type="reset"],
[type="submit"] {
  -webkit-appearance: button;
}

button:not(:disabled),
[type="button"]:not(:disabled),
[type="reset"]:not(:disabled),
[type="submit"]:not(:disabled) {
  cursor: pointer;
}

button::-moz-focus-inner,
[type="button"]::-moz-focus-inner,
[type="reset"]::-moz-focus-inner,
[type="submit"]::-moz-focus-inner {
  padding: 0;
  border-style: none;
}

input[type="radio"],
input[type="checkbox"] {
  box-sizing: border-box;
  padding: 0;
}

input[type="date"],
input[type="time"],
input[type="datetime-local"],
input[type="month"] {
  -webkit-appearance: listbox;
}

textarea {
  overflow: auto;
  resize: vertical;
}

fieldset {
  min-width: 0;
  padding: 0;
  margin: 0;
  border: 0;
}

legend {
  display: block;
  width: 100%;
  max-width: 100%;
  padding: 0;
  margin-bottom: .5rem;
  font-size: 1.5rem;
  line-height: inherit;
  color: inherit;
  white-space: normal;
}

progress {
  vertical-align: baseline;
}

[type="number"]::-webkit-inner-spin-button,
[type="number"]::-webkit-outer-spin-button {
  height: auto;
}

[type="search"] {
  outline-offset: -2px;
  -webkit-appearance: none;
}

[type="search"]::-webkit-search-decoration {
  -webkit-appearance: none;
}

::-webkit-file-upload-button {
  font: inherit;
  -webkit-appearance: button;
}

output {
  display: inline-block;
}

summary {
  display: list-item;
  cursor: pointer;
}

template {
  display: none;
}

[hidden] {
  display: none !important;
}
/*# sourceMappingURL=bootstrap-reboot.css.map */

sanitize.css

sanitize.css

以下のコマンドでダウンロードが可能です。

npm install --save sanitize.css

/* Document
 * ========================================================================== */

/**
 * Add border box sizing in all browsers (opinionated).
 */

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

/**
 * 1. Add text decoration inheritance in all browsers (opinionated).
 * 2. Add vertical alignment inheritance in all browsers (opinionated).
 */

::before,
::after {
  text-decoration: inherit; /* 1 */
  vertical-align: inherit; /* 2 */
}

/**
 * 1. Use the default cursor in all browsers (opinionated).
 * 2. Change the line height in all browsers (opinionated).
 * 3. Use a 4-space tab width in all browsers (opinionated).
 * 4. Remove the grey highlight on links in iOS (opinionated).
 * 5. Prevent adjustments of font size after orientation changes in
 *    IE on Windows Phone and in iOS.
 * 6. Breaks words to prevent overflow in all browsers (opinionated).
 */

html {
  cursor: default; /* 1 */
  line-height: 1.5; /* 2 */
  -moz-tab-size: 4; /* 3 */
  tab-size: 4; /* 3 */
  -webkit-tap-highlight-color: transparent /* 4 */;
  -ms-text-size-adjust: 100%; /* 5 */
  -webkit-text-size-adjust: 100%; /* 5 */
  word-break: break-word; /* 6 */
}

/* Sections
 * ========================================================================== */

/**
 * Remove the margin in all browsers (opinionated).
 */

body {
  margin: 0;
}

/**
 * Correct the font size and margin on `h1` elements within `section` and
 * `article` contexts in Chrome, Edge, Firefox, and Safari.
 */

h1 {
  font-size: 2em;
  margin: 0.67em 0;
}

/* Grouping content
 * ========================================================================== */

/**
 * Remove the margin on nested lists in Chrome, Edge, IE, and Safari.
 */

dl dl,
dl ol,
dl ul,
ol dl,
ul dl {
  margin: 0;
}

/**
 * Remove the margin on nested lists in Edge 18- and IE.
 */

ol ol,
ol ul,
ul ol,
ul ul {
  margin: 0;
}

/**
 * 1. Add the correct sizing in Firefox.
 * 2. Show the overflow in Edge 18- and IE.
 */

hr {
  height: 0; /* 1 */
  overflow: visible; /* 2 */
}

/**
 * Add the correct display in IE.
 */

main {
  display: block;
}

/**
 * Remove the list style on navigation lists in all browsers (opinionated).
 */

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

/**
 * 1. Correct the inheritance and scaling of font size in all browsers.
 * 2. Correct the odd `em` font sizing in all browsers.
 */

pre {
  font-family: monospace, monospace; /* 1 */
  font-size: 1em; /* 2 */
}

/* Text-level semantics
 * ========================================================================== */

/**
 * Remove the gray background on active links in IE 10.
 */

a {
  background-color: transparent;
}

/**
 * Add the correct text decoration in Edge 18-, IE, and Safari.
 */

abbr[title] {
  text-decoration: underline;
  text-decoration: underline dotted;
}

/**
 * Add the correct font weight in Chrome, Edge, and Safari.
 */

b,
strong {
  font-weight: bolder;
}

/**
 * 1. Correct the inheritance and scaling of font size in all browsers.
 * 2. Correct the odd `em` font sizing in all browsers.
 */

code,
kbd,
samp {
  font-family: monospace, monospace; /* 1 */
  font-size: 1em; /* 2 */
}

/**
 * Add the correct font size in all browsers.
 */

small {
  font-size: 80%;
}

/* Embedded content
 * ========================================================================== */

/*
 * Change the alignment on media elements in all browsers (opinionated).
 */

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

/**
 * Add the correct display in IE 9-.
 */

audio,
video {
  display: inline-block;
}

/**
 * Add the correct display in iOS 4-7.
 */

audio:not([controls]) {
  display: none;
  height: 0;
}

/**
 * Remove the border on iframes in all browsers (opinionated).
 */

iframe {
  border-style: none;
}

/**
 * Remove the border on images within links in IE 10-.
 */

img {
  border-style: none;
}

/**
 * Change the fill color to match the text color in all browsers (opinionated).
 */

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

/**
 * Hide the overflow in IE.
 */

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

/* Tabular data
 * ========================================================================== */

/**
 * Collapse border spacing in all browsers (opinionated).
 */

table {
  border-collapse: collapse;
}

/* Forms
 * ========================================================================== */

/**
 * Remove the margin on controls in Safari.
 */

button,
input,
select {
  margin: 0;
}

/**
 * 1. Show the overflow in IE.
 * 2. Remove the inheritance of text transform in Edge 18-, Firefox, and IE.
 */

button {
  overflow: visible; /* 1 */
  text-transform: none; /* 2 */
}

/**
 * Correct the inability to style buttons in iOS and Safari.
 */

button,
[type="button"],
[type="reset"],
[type="submit"] {
  -webkit-appearance: button;
}

/**
 * 1. Change the inconsistent appearance in all browsers (opinionated).
 * 2. Correct the padding in Firefox.
 */

fieldset {
  border: 1px solid #a0a0a0; /* 1 */
  padding: 0.35em 0.75em 0.625em; /* 2 */
}

/**
 * Show the overflow in Edge 18- and IE.
 */

input {
  overflow: visible;
}

/**
 * 1. Correct the text wrapping in Edge 18- and IE.
 * 2. Correct the color inheritance from `fieldset` elements in IE.
 */

legend {
  color: inherit; /* 2 */
  display: table; /* 1 */
  max-width: 100%; /* 1 */
  white-space: normal; /* 1 */
}

/**
 * 1. Add the correct display in Edge 18- and IE.
 * 2. Add the correct vertical alignment in Chrome, Edge, and Firefox.
 */

progress {
  display: inline-block; /* 1 */
  vertical-align: baseline; /* 2 */
}

/**
 * Remove the inheritance of text transform in Firefox.
 */

select {
  text-transform: none;
}

/**
 * 1. Remove the margin in Firefox and Safari.
 * 2. Remove the default vertical scrollbar in IE.
 * 3. Change the resize direction in all browsers (opinionated).
 */

textarea {
  margin: 0; /* 1 */
  overflow: auto; /* 2 */
  resize: vertical; /* 3 */
}

/**
 * Remove the padding in IE 10-.
 */

[type="checkbox"],
[type="radio"] {
  padding: 0;
}

/**
 * 1. Correct the odd appearance in Chrome, Edge, and Safari.
 * 2. Correct the outline style in Safari.
 */

[type="search"] {
  -webkit-appearance: textfield; /* 1 */
  outline-offset: -2px; /* 2 */
}

/**
 * Correct the cursor style of increment and decrement buttons in Safari.
 */

::-webkit-inner-spin-button,
::-webkit-outer-spin-button {
  height: auto;
}

/**
 * Correct the text style of placeholders in Chrome, Edge, and Safari.
 */

::-webkit-input-placeholder {
  color: inherit;
  opacity: 0.54;
}

/**
 * Remove the inner padding in Chrome, Edge, and Safari on macOS.
 */

::-webkit-search-decoration {
  -webkit-appearance: none;
}

/**
 * 1. Correct the inability to style upload buttons in iOS and Safari.
 * 2. Change font properties to `inherit` in Safari.
 */

::-webkit-file-upload-button {
  -webkit-appearance: button; /* 1 */
  font: inherit; /* 2 */
}

/**
 * Remove the inner border and padding of focus outlines in Firefox.
 */

::-moz-focus-inner {
  border-style: none;
  padding: 0;
}

/**
 * Restore the focus outline styles unset by the previous rule in Firefox.
 */

:-moz-focusring {
  outline: 1px dotted ButtonText;
}

/**
 * Remove the additional :invalid styles in Firefox.
 */

:-moz-ui-invalid {
  box-shadow: none;
}

/* Interactive
 * ========================================================================== */

/*
 * Add the correct display in Edge 18- and IE.
 */

details {
  display: block;
}

/*
 * Add the correct styles in Edge 18-, IE, and Safari.
 */

dialog {
  background-color: white;
  border: solid;
  color: black;
  display: block;
  height: -moz-fit-content;
  height: -webkit-fit-content;
  height: fit-content;
  left: 0;
  margin: auto;
  padding: 1em;
  position: absolute;
  right: 0;
  width: -moz-fit-content;
  width: -webkit-fit-content;
  width: fit-content;
}

dialog:not([open]) {
  display: none;
}

/*
 * Add the correct display in all browsers.
 */

summary {
  display: list-item;
}

/* Scripting
 * ========================================================================== */

/**
 * Add the correct display in IE 9-.
 */

canvas {
  display: inline-block;
}

/**
 * Add the correct display in IE.
 */

template {
  display: none;
}

/* User interaction
 * ========================================================================== */

/*
 * 1. Remove the tapping delay in IE 10.
 * 2. Remove the tapping delay on clickable elements
      in all browsers (opinionated).
 */

a,
area,
button,
input,
label,
select,
summary,
textarea,
[tabindex] {
  -ms-touch-action: manipulation; /* 1 */
  touch-action: manipulation; /* 2 */
}

/**
 * Add the correct display in IE 10-.
 */

[hidden] {
  display: none;
}

/* Accessibility
 * ========================================================================== */

/**
 * Change the cursor on busy elements in all browsers (opinionated).
 */

[aria-busy="true"] {
  cursor: progress;
}

/*
 * Change the cursor on control elements in all browsers (opinionated).
 */

[aria-controls] {
  cursor: pointer;
}

/*
 * Change the cursor on disabled, not-editable, or otherwise
 * inoperable elements in all browsers (opinionated).
 */

[aria-disabled="true"],
[disabled] {
  cursor: not-allowed;
}

/*
 * Change the display on visually hidden accessible elements
 * in all browsers (opinionated).
 */

[aria-hidden="false"][hidden] {
  display: initial;
}

[aria-hidden="false"][hidden]:not(:focus) {
  clip: rect(0, 0, 0, 0);
  position: absolute;
}

リセットCSS の人気ランキング

最後にリセットCSSダウンロード数人気ランキングをみていきましょう。
以下が現在(2019/6/30)人気な リセットCSS です。

参考:CSS Reset

1. Eric Meyer’s “Reset CSS” 2.0
2. HTML5 Doctor CSS Reset
3. Yahoo! (YUI 3) Reset CSS
4. Universal Selector ‘*’ Reset
5. Normalize.css

---

※追記
cssresetは、以前は上記のようなサイトでしたが、今現在CSSのチュートリアルが表示されています。

---

まとめ

今回はリセットCSSを8つ紹介しました。
Web開発で、どれを使うのか、はたまた使わないのか。もちろん、自分用にカスタマイズしたり、自作したものを使うという方法もあると思います。

自分にあったものを見つけてみてください。

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