リセットCSS | Webデザインラボ

リセットCSS

　Web制作者の方ならばすでにご存じと思われますが、文字のサイズやマージンの幅などWebブラウザはブラウザ毎に独自のCSSが設定されております。なので普通にHTMLを書いてサーバにアップしてブラウザで表示させても文字が小さすぎて見づらいなどというような不具合は避けることができます。ところが、今時HTMLだけ書いてそのままサーバにアップして「ホームページです。はい見てください。」というようなWebサイトはまずありませんね。コンテンツを元に、デザイナーさんがデザインしたデザインをコーダーさんがコーディングしてプログラマーさんがプログラムを組み込んで最後にサーバにアップという流れになると思います。その場合、ブラウザが持っているCSSはコーディングするコーダーさんにとってはとても邪魔な存在となります。ではその邪魔なCSSはどうしたらいいのか、そうリセットしてしまいます。ブラウザ毎に持っているフォントサイズやマージンなどの設定をクリアしてしまえばコーディングやプログラミングはとても楽になるため、ブラウザのCSSをリセットする、リセットCSSが使われるようになりました。リセットCSSは自分で作ることもできるし、Web上に公開されているリセットCSSをダウンロードして使うこともできます。一般的には後者が多いと思いますのでいくつか有名どころをピックアップしてご紹介します。

1. Eric Meyer’s CSS Reset

　作者はEric Meyer氏です。最終更新日が20110126と古いのですが、海外でも多く使われ今でも一般的なリセットCSSです。

http://meyerweb.com/eric/tools/css/reset/

/* 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;
}

2. HTML5 Doctor CSS ResetGet The Code

　Richard Clark氏がEric Meyers CSS resetをベースに改変したリセットCSSです。HTML5向けに調整されてあり、新しく追加された要素も加え、廃止された要素は除外して再設定されたものです。しかしなぜかEric Meyers CSS resetよりも更新日が古くなっております。

http://html5doctor.com/html-5-reset-stylesheet/

/* 
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;
}

3. Yahoo! CSS Reset(YUI 3)

　Yahoo! User Interface Library提供のリセットCSSです。使っていた方も多かったのではないでしょうか。しかしご存知の通り、米Yahoo!からはすでにJavaScriptライブラリ「YUI」の開発は行わないというアナウンスがなされております。

http://yuilibrary.com/yui/docs/cssreset/

<link rel="stylesheet" type="text/css" href="http://yui.yahooapis.com/3.18.1/build/cssreset/cssreset-min.css">

4. normalize.css

　Normalize.cssはそれぞれのブラウザが持っている有用なスタイルをなるべく残しつつ、それぞれのブラウザ毎の差が少なくなるように作られたリセットCSSです。

https://necolas.github.io/normalize.css/

/*! normalize.css v4.1.1 | MIT License | github.com/necolas/normalize.css */
/**
 * 1. Change the default font family in all browsers (opinionated).
 * 2. Prevent adjustments of font size after orientation changes in IE and iOS.
 */
html {
  font-family: sans-serif; /* 1 */
  -ms-text-size-adjust: 100%; /* 2 */
  -webkit-text-size-adjust: 100%; /* 2 */
}
/**
 * Remove the margin in all browsers (opinionated).
 */
body {
  margin: 0;
}
/* HTML5 display definitions
   ========================================================================== */
/**
 * Add the correct display in IE 9-.
 * 1. Add the correct display in Edge, IE, and Firefox.
 * 2. Add the correct display in IE.
 */
article,
aside,
details, /* 1 */
figcaption,
figure,
footer,
header,
main, /* 2 */
menu,
nav,
section,
summary { /* 1 */
  display: block;
}
/**
 * Add the correct display in IE 9-.
 */
audio,
canvas,
progress,
video {
  display: inline-block;
}
/**
 * Add the correct display in iOS 4-7.
 */
audio:not([controls]) {
  display: none;
  height: 0;
}
/**
 * Add the correct vertical alignment in Chrome, Firefox, and Opera.
 */
progress {
  vertical-align: baseline;
}
/**
 * Add the correct display in IE 10-.
 * 1. Add the correct display in IE.
 */
template, /* 1 */
[hidden] {
  display: none;
}
/* Links
   ========================================================================== */
/**
 * 1. Remove the gray background on active links in IE 10.
 * 2. Remove gaps in links underline in iOS 8+ and Safari 8+.
 */
a {
  background-color: transparent; /* 1 */
  -webkit-text-decoration-skip: objects; /* 2 */
}
/**
 * Remove the outline on focused links when they are also active or hovered
 * in all browsers (opinionated).
 */
a:active,
a:hover {
  outline-width: 0;
}
/* Text-level semantics
   ========================================================================== */
/**
 * 1. Remove the bottom border in Firefox 39-.
 * 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 */
}
/**
 * Prevent the duplicate application of `bolder` by the next rule in Safari 6.
 */
b,
strong {
  font-weight: inherit;
}
/**
 * Add the correct font weight in Chrome, Edge, and Safari.
 */
b,
strong {
  font-weight: bolder;
}
/**
 * Add the correct font style in Android 4.3-.
 */
dfn {
  font-style: italic;
}
/**
 * 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;
}
/**
 * Add the correct background and color in IE 9-.
 */
mark {
  background-color: #ff0;
  color: #000;
}
/**
 * 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;
}
/**
 * Hide the overflow in IE.
 */
svg:not(:root) {
  overflow: hidden;
}
/* Grouping content
   ========================================================================== */
/**
 * 1. Correct the inheritance and scaling of font size in all browsers.
 * 2. Correct the odd `em` font sizing in all browsers.
 */
code,
kbd,
pre,
samp {
  font-family: monospace, monospace; /* 1 */
  font-size: 1em; /* 2 */
}
/**
 * Add the correct margin in IE 8.
 */
figure {
  margin: 1em 40px;
}
/**
 * 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 */
}
/* Forms
   ========================================================================== */
/**
 * 1. Change font properties to `inherit` in all browsers (opinionated).
 * 2. Remove the margin in Firefox and Safari.
 */
button,
input,
select,
textarea {
  font: inherit; /* 1 */
  margin: 0; /* 2 */
}
/**
 * Restore the font weight unset by the previous rule.
 */
optgroup {
  font-weight: bold;
}
/**
 * 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;
}
/**
 * 1. Prevent a WebKit bug where (2) destroys native `audio` and `video`
 *    controls in Android 4.
 * 2. Correct the inability to style clickable types in iOS and Safari.
 */
button,
html [type="button"], /* 1 */
[type="reset"],
[type="submit"] {
  -webkit-appearance: button; /* 2 */
}
/**
 * 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;
}
/**
 * Change the border, margin, and padding in all browsers (opinionated).
 */
fieldset {
  border: 1px solid #c0c0c0;
  margin: 0 2px;
  padding: 0.35em 0.625em 0.75em;
}
/**
 * 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 */
}
/**
 * Remove the default vertical scrollbar in IE.
 */
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 and cancel buttons in Chrome and Safari on OS X.
 */
[type="search"]::-webkit-search-cancel-button,
[type="search"]::-webkit-search-decoration {
  -webkit-appearance: none;
}
/**
 * Correct the text style of placeholders in Chrome, Edge, and Safari.
 */
::-webkit-input-placeholder {
  color: inherit;
  opacity: 0.54;
}
/**
 * 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 */
}

5. ress

　ressはnormalize.cssをカスタマイズしたリセットCSSです。ブラウザ毎に違った各要素の相違を吸収するようにカスタマイズされたリセットCSSです。

https://github.com/filipelinhares/ress

/*!
 * ress.css • v1.1.1
 * 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 {
  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 */
* {
  background-repeat: no-repeat; /* Set `background-repeat: no-repeat` to all elements */
  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;
}

6. Universal Selector Reset

　結局ユニバーサルセレクタでリセットしちゃってませんか？！。今後Webデザインラボでも改めてリセットCSSをまとめてみたいと思います。

* {
  margin: 0;
  padding: 0;
}

　いかがでしたでしょうか。リセットCSSもいろいろとあって選ぶのも迷うところです(汗。どのリセットCSSも自由に使えますが、ライセンス表記は消さないよう注意してください。