var txt = document.getElementById("txt");
??? //定義"改變顏色"的函數
??? function color(){
??????? txt.style.color="red";
??????? txt.style.backgroundColor="#ccc";
??? }

??? //定義"改變寬高"的函數
??? function size(){
??????? txt.style.width="400px";
??????? txt.style.height="300px"
??? }

??? //定義"隱藏內容"的函數
??? function hide(){
??????? txt.style.display="none";
??? }

??? //定義"顯示內容"的函數
??? function show(){
??????? txt.style.display="block";
??? }

??? //定義"取消設置"的函數
??? function resetText(){
??????? var reset = confirm("是否取消設置");
??????? if( reset ==true ){
??????????? txt.removeAttribute("style");
??????? }
??? }