CSS Resets & Normalizing

As developers, we want our HTML elements to look the same way regardless of which browser is being used to view our pages. Unfortunately, this isn’t the case due to the way browsers run.

Each browser has its own default stylesheet, which specifies some minimal rules that apply to elements.

For example: an unstyled <h1> element will often have a slightly different amount of padding, depending on which browser is used.

Most of the time these style defaults are useful. However, there will come a time when a bug occurs in a particular browser, as a result of these differing defaults.

To avoid these inconsistencies we use CSS Resets & Normalization!

CSS Resets

A CSS Reset will remove all the browsers’ default styles. Leaving us to define the styles that we want, according to our needs.

There are multiple types of CSS Reset on the web. By far, the most popular is the Meyer 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;
}

Here all HTML tags are given no padding, no margin, no border, an equal font-size and a baseline alignment.

Whilst it’s great to start a project on a level playing field. As you can see, CSS Resets are quite ugly & have lots of unnecessary overrides.

There are a few more widely used resets that have come along post HTML5, such as Richard Clark’s HTML5 Reset, Cleanslate & mini reset to name a few.

Many developers go for a more minimal approach, by just removing any padding & margins:

* {
  padding: 0;
  margin: 0;
}

Normalization

Normalization is an alternative to resets that is less “aggressive”. Rather than removing all defaults, it’ll just remove the browser inconsistencies, while keeping in place a basic set of defaults.

Normalize.css was created to provide this cross-browser consistency.

In accordance with the W3C standards, it won’t remove styling from elements that are already consistent across browsers.

Here is the code, heavily commented so you know exactly that its doing:

/*! 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;
}

Wrapping up

As to which you should use, it’s really up to you! You could also choose a combination of both or even to write your own.

However, you can’t go wrong running Normalize CSS & peppering in a few Resets on an as-needed basis 👌.

Related Posts:

• Media Queries
• Feature Queries