Nesting CSS classes

Can I do something like the following?

.class1{some stuff}

.class2{class1;some more stuff}

Update 1: There is a CSS3 spec for CSS level 3 nesting. It's currently a draft. https://tabatkins.github.io/specs/css-nesting/

Update 2 (2019): We now have a CSSWG editors draft https://drafts.csswg.org/css-nesting-1/

Update 3 (2022): We now have a W3C First Public Working Draft https://www.w3.org/TR/css-nesting-1/

If approved, the syntax would look like this:

table.colortable {
  & td {
    text-align:center;
    &.c { text-transform:uppercase }
    &:first-child, &:first-child + td { border:1px solid black }
  }
  & th {
    text-align:center;
    background:black;
    color:white;
  }
}

.foo {
  color: red;
  @nest & > .bar {
    color: blue;
  }
}

.foo {
  color: red;
  @nest .parent & {
    color: blue;
  }
}

Not possible with vanilla CSS. However you can use something like:

• Sass

> Sass makes CSS fun again. Sass is an > extension of CSS3, adding nested > rules, variables, mixins, selector > inheritance, and more. It’s translated > to well-formatted, standard CSS using > the command line tool or a > web-framework plugin.

Or

• Less

> Rather than constructing long selector > names to specify inheritance, in Less > you can simply nest selectors inside > other selectors. This makes > inheritance clear and style sheets > shorter.

Example:

#header {
  color: red;
  a {
    font-weight: bold;
    text-decoration: none;
  }
}

Not with pure CSS. The closest equivalent is this:

.class1, .class2 {
    some stuff
}

.class2 {
    some more stuff
}

Not directly. But you can use extensions such as LESS to help you achieve the same.

No.

You can use grouping selectors and/or multiple classes on a single element, or you can use a template language and process it with software to write your CSS.

See also my article on CSS inheritance.

I do not believe this is possible. You could add class1 to all elements which also have class2. If this is not practical to do manually, you could do it automatically with JavaScript (fairly easy to do with jQuery).

Try this...

Give the element an ID, and also a class Name. Then you can nest the #IDName.className in your CSS.

Here's a better explanation https://css-tricks.com/multiple-class-id-selectors/