CSS: Selector Tutorial

By Xah Lee. Date: . Last updated: .

The following are most common patterns in using CSS. You should memorize them by heart.

Match Tag Names

Some common examples of setting appearance for HTML elements.

body {font-family:sans-serif}

h1,h2,h3,h4,h5,h6 {font-family:serif}

p {line-height:1.5}

blockquote {color:navy}

img {margin:1px}

Match Class Value

/* matches any tag of class “xyz”*/
.xyz {color:red}

the above will match both of the following:

<div class="xyz">…</div>
<span class="xyz"></span>

Note: a HTML element can have more than one class.

[see HTML: Multiple Class Attribute Values]

Match Tag Name and Class Value

/* matches any div of class “xyz”*/
div.xyz {color:red}

the above will match

<div class="xyz">…</div>

Here's another example:

/* matches any span of class “ab”*/
span.ab {color:blue}

This will match:

<span class="ab"></span>

Match a Tag's ID

/* matches any tag with id of “xyz”*/
#xyz {color:red}

the above will match any of:

<div id="xyz"></div>
<span id="xyz"></span>
<p id="xyz"></p>

Note: a tag's id should be unique on a page. A page cannot have two tags having the same id. A frame [see HTML: Split Windows; Frameset] or iframe [see HTML: Iframe] counts as separate pages.

Change Link Appearance

Example of removing the underline in links.

a:link {text-decoration:none}
a:visited {text-decoration:none}

[see CSS: Text Decoration: Underline, Overline, Line-Through]

Multiple Tags A, B, C

If you have multiple tags and want them all to have the same appearance, you can use comma.

For example, this:

span.x, span.y, span.z {color:red}

is equivalent to:

span.x {color:red}
span.y {color:red}
span.z {color:red}

Match Nested Tags (all levels)

Sometimes, you want to match a tag only if it is nested inside another tag (regardless how many levels deep). You can use the space to specify this, like this:

div.abc span.xyz {color:red}

In the above example, it'll match any HTML span with attribute class="xyz" inside div with attribute class="abc" .

<div class="abc">

 Once <span class="xyz">upon</span> a time,

 <div>
 some <span class="xyz">thing</span>
 </div>

</div>

Parent Child Relation (Nested Tags (1st level only))

Sometimes you want to match a tag only if it is a immediate child of a given parent tag. You can use the > to specify a parent-child relationship.

Here's a example:

div > span {color:red}

In the following HTML code, the CSS code above will match the “upon” but not “you”.

<div>
once <span>upon</span> a time
<footer>Thank <span>you</span> for reading</footer>
</div>

Complete List of CSS Selector Syntax

CSS Selector Syntax

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