var text = document.querySelector(".text");
            var search = document.querySelector("input");
            const btn = document.querySelector("button");
            var article=String(text.innerText)//保存原文本
            btn.onclick = () => {
                // 补全代码
                var key=new String(search.value)
                var newV=article.replace(new RegExp(key,'g'),`
                    <b style="background-color:yellow">${key}</b>
                `)
                text.innerHTML=newV
            }