One < style > corresponding one CSSStyleSheet object (in document.styleSheets), but how to find it, such as the CSSStyleSheet object corresponding < style id="-yCoder-styles" >...< /style>
console.log(document.styleSheets.length);
var style = document.createElement('style');
style.title = "-yCoder-styles";
style.type= 'text/css';
style.id = "-yCoder-styles";
document.head.appendChild(style);
//how to get the corresponding CSSStyleSheet instance from document.styleSheets
console.log(document.styleSheets.length);
var styleSheet = document.styleSheets[document.styleSheets.length - 1];
console.log(styleSheet.title == style.title);