a library of functions for ripping around the CSSOM, finding, operating on, or working with the CSS stylesheets and rules you find

css-building-blocks.js

var csstools = (function() {

  function parse(string) {
    var iframe = document.createElement('iframe')
    document.head.appendChild(iframe)
    var style = iframe.contentDocument.createElement('style')
    style.textContent = string
    iframe.contentDocument.head.appendChild(style)
    var stylesheet = iframe.contentDocument.styleSheets[0]
    document.head.removeChild(iframe)
    return stylesheet
  }

  function process(stylesheet, callback) {
    function readRules(list) {
      Array.prototype.slice.call(list.cssRules).forEach(function(rule) {
        callback(rule)
        if (rule.cssRules !== undefined) {
          readRules(rule)
        }
      })
    }
    if (
      [stylesheet, stylesheet.cssRules, callback].every(function(thing) {
        return thing !== undefined
      })
      && typeof callback === 'function'
    ) {
      readRules(stylesheet)
      return stylesheet
    }
  }

  function stringify(object) {
    function rule(rule) {
      return rule.cssText || ''
    }
    return Array.isArray(object)
    ? object.map(stringify).join('\n')
    : (object.cssRules
      ? Array.prototype.slice.call(object.cssRules)
          .map(rule)
          .join('\n')
      : rule(object)
    )
  }

  function all() {
    return Array.prototype.slice.call(document.styleSheets).map(function(stylesheet) {
      try {
        stylesheet.cssRules
      }
      catch(error) {
        return null
      }
      return stylesheet
    }).filter(Boolean)
  }

  function filter(stylesheet, test) {
    var output = {cssRules: []}
    process(
      stylesheet,
      function(rule) {
        if (test(rule)) {
          output.cssRules.push(rule)
        }
      }
    )
    return output
  }

  function selector(string) {
    return all().map(function(stylesheet) {
      return filter(
        stylesheet,
        function(rule) {
          return rule.selectorText && rule.selectorText.indexOf(string) !== -1
        }
      )
    })  
  }

  function property(string) {
    return all().map(function(stylesheet) {
      return filter(
        stylesheet,
        function(rule) {
          return rule.style && Array.prototype.slice.call(rule.style).some(function(property) {
            return property.indexOf(string) !== -1
          })
        }
      )
    })
  }

  function value(string) {
    return all().map(function(stylesheet) {
      return filter(
        stylesheet,
        function(rule) {
          return rule.style && Array.prototype.slice.call(rule.style).some(function(prop) { 
            return rule.style.getPropertyValue(prop).indexOf(string) !== -1
          })
        }
      )
    })
  }

  function query(string) {
    return all().map(function(stylesheet) {
      return filter(
        stylesheet,
        function(rule) {
          return rule.media && rule.media.mediaText.indexOf(string) !== -1
        }
      )
    })
  }

  function remove(object) {
    Array.isArray(object)
    ? object.forEach(remove)
    : (object.cssRules
      ? Array.prototype.slice.call(object.cssRules).map(remove)
      : object.parentRule
      ? object.parentRule.deleteRule(
        Array.prototype.slice.call(object.parentRule.cssRules).indexOf(object)
      )
      : object.parentStyleSheet.deleteRule(
        Array.prototype.slice.call(object.parentStyleSheet.cssRules).indexOf(object)
      )
    )
  }

  return {
    parse: parse,
    process: process,
    stringify: stringify,
    all: all,
    filter: filter,
    selector: selector,
    property: property,
    value: value,
    query: query,
    remove: remove
  }

})()

css-building-blocks.min.js

var csstools=function(){function g(a,b){function c(a){Array.prototype.slice.call(a.cssRules).forEach(function(a){b(a);void 0!==a.cssRules&&c(a)})}if([a,a.cssRules,b].every(function(a){return void 0!==a})&&"function"===typeof b)return c(a),a}function h(a){function b(a){return a.cssText||""}return Array.isArray(a)?a.map(h).join("\n"):a.cssRules?Array.prototype.slice.call(a.cssRules).map(b).join("\n"):b(a)}function d(){return Array.prototype.slice.call(document.styleSheets).map(function(a){try{a.cssRules}catch(b){return null}return a}).filter(Boolean)}function e(a,b){var c={cssRules:[]};g(a,function(a){b(a)&&c.cssRules.push(a)});return c}function f(a){Array.isArray(a)?a.forEach(f):a.cssRules?Array.prototype.slice.call(a.cssRules).map(f):a.parentRule?a.parentRule.deleteRule(Array.prototype.slice.call(a.parentRule.cssRules).indexOf(a)):a.parentStyleSheet.deleteRule(Array.prototype.slice.call(a.parentStyleSheet.cssRules).indexOf(a))}return{parse:function(a){var b=document.createElement("iframe");document.head.appendChild(b);var c=b.contentDocument.createElement("style");c.textContent=a;b.contentDocument.head.appendChild(c);a=b.contentDocument.styleSheets[0];document.head.removeChild(b);return a},process:g,stringify:h,all:d,filter:e,selector:function(a){return d().map(function(b){return e(b,function(b){return b.selectorText&&-1!==b.selectorText.indexOf(a)})})},property:function(a){return d().map(function(b){return e(b,function(b){return b.style&&Array.prototype.slice.call(b.style).some(function(b){return-1!==b.indexOf(a)})})})},value:function(a){return d().map(function(b){return e(b,function(b){return b.style&&Array.prototype.slice.call(b.style).some(function(c){return-1!==b.style.getPropertyValue(c).indexOf(a)})})})},query:function(a){return d().map(function(b){return e(b,function(b){return b.media&&-1!==b.media.mediaText.indexOf(a)})})},remove:f}}();