下面展示了 6 个仓库代码，来说明现在 CSS 框架主要使用的样式重置方案：一个是 CSS Reset，一个是 CSS Normalize。其实两者并非是我们所想象的那样水火不容，相反，它们还能结合使用，用来获得更加舒适的样式控制体验。

modern-css-reset

现在已不再像 IE 6 时代那样，需要很重量的重置代码。现代浏览器对标准的兼容更加完善，各浏览器在样式表现上也更加统一，因此 CSS 重置代码也应该变得比以前更加轻量。

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

/* Remove default padding */
ul[class],
ol[class] {
  padding: 0;
}

/* Remove default margin */
body,
h1,
h2,
h3,
h4,
p,
ul[class],
ol[class],
li,
figure,
figcaption,
blockquote,
dl,
dd {
  margin: 0;
}

/* Set core body defaults */
body {
  min-height: 100vh;
  scroll-behavior: smooth;
  text-rendering: optimizeSpeed;
  line-height: 1.5;
}

/* Remove list styles on ul, ol elements with a class attribute */
ul[class],
ol[class] {
  list-style: none;
}

/* A elements that don't have a class get default styles */
a:not([class]) {
  text-decoration-skip-ink: auto;
}

/* Make images easier to work with */
img {
  max-width: 100%;
  display: block;
}

/* Natural flow and rhythm in articles by default */
article > * + * {
  margin-top: 1em;
}

/* Inherit fonts for inputs and buttons */
input,
button,
textarea,
select {
  font: inherit;
}

/* Remove all animations and transitions for people that prefer not to see them */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

minireset.css

以下是著名 CSS 框架 Bulma 使用的基础重置库。

/*! minireset.css v0.0.6 | MIT License | github.com/jgthms/minireset.css */
html,
body,
p,
ol,
ul,
li,
dl,
dt,
dd,
blockquote,
figure,
fieldset,
legend,
textarea,
pre,
iframe,
hr,
h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0;
  padding: 0;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-size: 100%;
  font-weight: normal;
}

ul {
  list-style: none;
}

button,
input,
select,
textarea {
  margin: 0;
}

html {
  box-sizing: border-box;
}

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

img,
video {
  height: auto;
  max-width: 100%;
}

iframe {
  border: 0;
}

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

td,
th {
  padding: 0;
}

td:not([align]),
th:not([align]) {
  text-align: left;
}

normalize.css

其实可以把 normalize.css 看成是“轻度的重置”，只不过它重置的方向是把浏览器中的元素按照标准的、一致性上的渲染上做努力的。

/*! 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;
}

modern-normalize

是 normalize.css 的一个 Fork 版本，但只兼容最新的浏览器，所以删去了不少的样式，也更小。

正如项目发起人所说：该仓库目标就是为了让自己过时，当浏览器之间不再存在需要修复的样式一致性问题时，也就是这个项目死去之时，因为仓库文件没有需要写的代码了。

/*! modern-normalize v0.6.0 | MIT License | https://github.com/sindresorhus/modern-normalize */

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

/**
Use a better box model (opinionated).
*/

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

/**
Use a more readable tab size (opinionated).
*/

:root {
	-moz-tab-size: 4;
	tab-size: 4;
}

/**
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;
}

/**
Improve consistency of default fonts in all browsers. (https://github.com/sindresorhus/modern-normalize/issues/3)
*/

body {
	font-family:
		system-ui,
		-apple-system, /* Firefox supports this but not yet `system-ui` */
		'Segoe UI',
		Roboto,
		Helvetica,
		Arial,
		sans-serif,
		'Apple Color Emoji',
		'Segoe UI Emoji';
}

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

/**
Add the correct height in Firefox.
*/

hr {
	height: 0;
}

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

/**
Add the correct text decoration in Chrome, Edge, and Safari.
*/

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

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

b,
strong {
	font-weight: bolder;
}

/**
1. Improve consistency of default fonts in all browsers. (https://github.com/sindresorhus/modern-normalize/issues/3)
2. Correct the odd 'em' font sizing in all browsers.
*/

code,
kbd,
samp,
pre {
	font-family:
		SFMono-Regular,
		Consolas,
		'Liberation Mono',
		Menlo,
		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;
}

/*
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 */
}

/**
Remove the inheritance of text transform in Edge and Firefox.
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;
}

/**
Remove the padding so developers are not caught out when they zero out 'fieldset' elements in all browsers.
*/

legend {
	padding: 0;
}

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

progress {
	vertical-align: baseline;
}

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

[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 Chrome and Safari.
*/

summary {
	display: list-item;
}

sanitize.css

也是 normalize.css 的一个 Fork 版本。但区别是：normalize.css 样式遵循 CSS 规范；sanitize.css 样式遵循开发人员共同的期望和偏好；而 reset.css 是为了取消所有元素的样式。sanitize.css 会和 normalize.css 保持同步的。

/* 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;
}

Bootstrap Reboot

Bootstrap 在 v4 版本引入了 Reboot 的概念。这也许从某方面表现了 CSS Normalize 和 CSS Reset 并非是两个相互冲突的概念，而是可以相互融合使用的。

Bootstrap Reboot 的作用是为框架内容的编写提供一个基准，在此之上在进行框架的构建将更加方便。

/*!
 * 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;
}

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;
  background-color: #fff;
  -webkit-text-size-adjust: 100%;
  -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
}

[tabindex="-1"]:focus:not(:focus-visible) {
  outline: 0 !important;
}

hr {
  margin: 1rem 0;
  color: inherit;
  background-color: currentColor;
  border: 0;
  opacity: 0.25;
}

hr:not([size]) {
  height: 1px;
}

h1, h2, h3, h4, h5, h6 {
  margin-top: 0;
  margin-bottom: 0.5rem;
  font-weight: 500;
  line-height: 1.2;
}

h1 {
  font-size: 2.5rem;
}

h2 {
  font-size: 2rem;
}

h3 {
  font-size: 1.75rem;
}

h4 {
  font-size: 1.5rem;
}

h5 {
  font-size: 1.25rem;
}

h6 {
  font-size: 1rem;
}

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;
  -webkit-text-decoration-skip-ink: none;
  text-decoration-skip-ink: none;
}

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

ol,
ul {
  padding-left: 2rem;
}

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: 0.875em;
}

sub,
sup {
  position: relative;
  font-size: 0.75em;
  line-height: 0;
  vertical-align: baseline;
}

sub {
  bottom: -.25em;
}

sup {
  top: -.5em;
}

a {
  color: #0d6efd;
  text-decoration: none;
}

a:hover {
  color: #024dbc;
  text-decoration: underline;
}

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

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

pre {
  display: block;
  margin-top: 0;
  margin-bottom: 1rem;
  overflow: auto;
  font-size: 0.875em;
}

pre code {
  font-size: inherit;
  color: inherit;
  word-break: normal;
}

code {
  font-size: 0.875em;
  color: #d63384;
  word-wrap: break-word;
}

a > code {
  color: inherit;
}

kbd {
  padding: 0.2rem 0.4rem;
  font-size: 0.875em;
  color: #fff;
  background-color: #212529;
  border-radius: 0.2rem;
}

kbd kbd {
  padding: 0;
  font-size: 1em;
  font-weight: 700;
}

figure {
  margin: 0 0 1rem;
}

img {
  vertical-align: middle;
}

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

table {
  border-collapse: collapse;
}

caption {
  padding-top: 0.5rem;
  padding-bottom: 0.5rem;
  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;
}

[list]::-webkit-calendar-picker-indicator {
  display: none;
}

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;
}

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

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

textarea {
  overflow: auto;
  resize: vertical;
}

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

legend {
  float: left;
  width: 100%;
  padding: 0;
  margin-bottom: 0.5rem;
  font-size: 1.5rem;
  line-height: inherit;
  color: inherit;
  white-space: normal;
}

mark {
  padding: 0.2em;
  background-color: #fcf8e3;
}

progress {
  vertical-align: baseline;
}

::-webkit-datetime-edit {
  overflow: visible;
  line-height: 0;
}

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

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

::-webkit-color-swatch-wrapper {
  padding: 0;
}

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

output {
  display: inline-block;
}

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

template {
  display: none;
}

main {
  display: block;
}

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

结语

我比较喜欢 Sarah Gebauer 说的这段话：

归根结底，这两个（CSS Reset 和 CSS Normalize）都不过是工具，如果你觉得自己对 normalize.css 更了解，并想要继续使用它，那就接着用。我过去曾经使用过 CSS Normalize（现在是 CSS Reset），如果我周围的人更喜欢使用 normalize.css，那么我也会再次使用它的。

到底该用哪个，首先取决于与你熟悉哪一个；另外，团队的选择，也会影响我们的决策。

值得注意的是，Bootstrap Reboot 的思想还是挺值得借鉴的。我们没有必要全部使用某一个方案大而全的代码，而是根据实际项目需要，使用其中的部分代码，再加上我们的自定义代码就行了。

（完）