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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              body {
  font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Oxygen-Sans,Ubuntu,Cantarell,"Helvetica Neue",sans-serif;
  
  --html:(
    <h1>Hello ${data.name}!</h1>
    <p>This page was constructed entirely within the CSS file. That includes all the data, markup, scripts, and also styles.</p>
    <p>For more information, see the <a href="https://github.com/scottkellum/CJSS">CJSS</a> repo on Github.</p>
    <p>click the items below to toggle them. This is to illustrate component-level JS in the CSS file.</p>
    <nav>Nav heading</nav>
  );
  --data:(
    name:'world',
  );
}

nav {
  --data:(
    links: ['one', 'two', 'three'],
  );
  --html:(
    <h2>${yield}</h2>
    <div class="item">${data.links[0]}</div>
    <div class="item">${data.links[1]}</div>
    <div class="item">${data.links[2]}</div>
  );
}

nav .item {
  cursor: pointer;
  --js:(
    function toggle() {
      this.classList.toggle('active');
    }
    this.addEventListener('click', toggle );
  );
}
nav .item.active {
  color: red;
}

/* Run a script like typetura.js */
script {
  --data:(
    say: 'Hello world!'
  );
  --js:(
    console.log(data.say);
  );
}
            
          
!
            
              (() => {

  /**
   * Get value of a rule's property and remove surrounding parentheses.
   * @param rule The CSSStyleRule, which to select from.
   * @param propertyName The name/key which to select.
   **/
  function getPureProperty(rule, propertyName) {
    const raw = rule.style.getPropertyValue(propertyName);
    return raw.trim().slice(1, -1);
  }

  /**
   * Runs CJSS rules - CSS rules with the special properties --html, --js and --data.
   * @param rules An array of CJSS rules.
   **/
  function cjss(rules) {
    for (let rule of rules) {
      const ruleName = rule.constructor.name;

      // Handle imports (recursive)
      if (ruleName === 'CSSImportRule') {
        const importedRules = rule.styleSheet.cssRules;
        cjss(importedRules);
      }

      else if (ruleName === 'CSSStyleRule') {
        const selector = rule.style.parentRule.selectorText;
        const elements = document.querySelectorAll(selector);

        let js = getPureProperty(rule, '--js');
        let html = getPureProperty(rule, '--html');
        let data = getPureProperty(rule, '--data');

        if (data) {
          data = eval(`({ ${ data } })`);
        }

        if (html) {
          for (let element of elements) {
            const yield = element.innerHTML;

            // eval could be removed with a "shallow parser".
            element.innerHTML = eval(`\`${ html }\``);
          }
        }

        if (js) {
          if (selector === 'script') {
            eval(js);
            continue;
          }

          // There is a lot of room for optimization here.
          for (let n = 0; n < elements.length; n++) {
            eval(js.replace(/this/g, `document.querySelectorAll('${ selector }')[${ n }]`));
          }
        }
      }
    }
  }

  /**
   * Plug every stylesheet in the document into the cjss function.
   */
  function initialize() {
    for (let sheet of document.styleSheets) {
      const rules = sheet.rules || sheet.cssRules;

      if (!rules || !rules.length) continue;
      cjss(rules);
    }
  }

  document.addEventListener('DOMContentLoaded', initialize);
})();
            
          
!
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