This table has many of the common selectors used in CSS. It is not exhaustive, there are combinations not displayed here, but it does have the ones you will use most on a normal basis.
Element types:
Selector
Example
Description
tag
p
Selects all p elements
.class
.container
Selects all elements whose class="container"
#id
#myButton
Selects an element whose id="myButton"
Combinations:
Selector
Example
Description
element
h1
Selects all h1 elements
element, element
div, h1
Selects all div elements and all h1 elements (regardless of level)
element element
div h1
Selects all h1 elements inside of div elements
element > element
div > h1
Selects all h1 elements whose direct parent is a div
element + element
p + p
Selects p elements that are the next element after another p element
Attribute Selectors:
Selector
Example
Description
[attribute]
input[type]
Selects all input elements that are using the type attribute
[attribute=value]
input[type=text]
Selects all input elements of type text (text boxes)
[attribute^=value]
[class^=grid]
Selects all elements that start with a class name of "grid", ie: grid__row
[attribute$=value]
[class$=primary]
Selects all elements that end with a class name of "primary", ie: button--primary
Pseudo-Classes:
Selector
Example
Description
:active
button:active
Selects the button that is currently being pressed or touched
:focus
input:focus
Selects the input currently in focus
:hover
a:hover
Selects a link that the mouse pointer is over.
Index Selectors (Subset of Pseudo-Classes):
Selector
Example
Description
:nth-child(n)
p:nth-child(3)
Selects every p element that is the third child of its parent.
:nth-child(odd or even)
p:nth-child(odd)
Selects every odd numbered p element inside of its parent.
:nth-last-child(n)
p:nth-last-child(3)
Selects every p element that is the third from last child of its parent
:nth-of-type(n)
p:nth-of-type(3)
Selects every p element that is the third p element inside its parent
:nth-last-of-type(n)
p:nth-last-of-type(3)
Selects every p element that is the third from last p element inside its parent