Question

Is there a difference between .class element and element.class in a CSS selector?

I had always been shown element.class but just the other day came across a CSS file at work that had .class element and wanted to know if this was just a style choice (in which case I would make my changes match), or if there was a specific reason (in which case I would not necessarily want to make my changes match).

Answer 1

element.class selects all <element />s with that class. .class element selects all <element />s that are descendants of elements that have that class.

For example, HTML:

<div class='wrapper'>
  <div class='content'></div>
  <div></div>
  <div class='footer'></div>
</div>

For example, CSS:

div.wrapper {
  background-color: white; /* the div with wrapper class will be white */
}

.wrapper div {
  background-color: red;   /* all 3 child divs of wrapper will be red */
}