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                <h1>Style Queries Demo</h1>
  This demo is based on
  an article at
  <a href=""></a> -
  and demonstrates different approaches
  for replacing the 'variable space hack'
  with container style queries.
  The main limitation here
  is that it's not possible for an element
  to query itself,
  so some form of nesting is required.


<section class="context">
  <h2>Contextual variable setting</h2>
    The <code>--button: raised;</code> value
    is set on the wrapping section,
    allowing the <code>button</code>
    to query the value.

<section class="internal">
  <h2>Internal variable setting</h2>
    The <code>--button: raised;</code> value
    is set on the <code>button</code> itself,
    and the styles are applied
    to a nested <code>span</code>.
  <button class="wrap"><span>Raised</span></button>


button.wrap > span {
  padding: 0.6em 1em;
  border: 1px solid;
  border-radius: 0.2em;
  background: hsl(200 100% 50%);
  color: white;
  font: 600 100%/1 sans-serif;
  cursor: pointer;

button:hover {
  background-color: hsl(200 100% 40%);

.internal button {
  --button: raised;

@container style(--button: raised) {
  button.wrap > span {
    border: 1px solid rgb(0 0 0 / 0.1);
    background: linear-gradient(hsl(0 0% 100% / 0.3), transparent)
      hsl(200, 100%, 50%);
    box-shadow: 0 1px hsl(0 0% 100% / 0.8) inset,
      0 0.1em 0.1em -0.1em rgb(0 0 0 / 0.2);
    text-shadow: 0 -1px 1px rgb(0 0 0 / 0.3);

  .wrap > span:active {
    box-shadow: 0 1px 0.2em black inset;

@layer init {
  html {
    height: 100%;
    display: grid;
  body {
    padding: 1em;
  button {
    padding: 0;
    margin: 0;
    border: 0;
    font: inherit;