<jquery>滚动例子
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>修改CSS样式</title> <style> * { margin: 0; padding: 0; } .c1,.c2,.c3{ width: 100px; height: 100px; background-color: green; } .c2 { position: relative; top: 200px; left: 200px; background-color: red; } .c3 { position: absolute; left: 100px; top: 100px; background-color: blue; } .hide { display: none; } .c4 { width: 100px; height: 100px; background-color: #111111; } </style> </head> <body> <div class="c4 hide"></div> <p>小强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <p>er强</p> <div class="c4 hide"></div> <div class="c1 hide">我的div</div> <div class="c2"> <div class="c3">我的div</div> </div> <script src="jquery-3.2.1.min.js"></script> <script> $("p").click(function () { // $(this).css("color","red"); // $(this).css("font-size","30px"); //修改多个样式,用字典键值对 $(this).css({"color":"red","font-size":"30px"}); }); //相对最初的移动 // $(".c1").offset(); $(".c1").offset({top:100,left:100}); //相对父标签的移动 $(".c3").position(); $(window).scroll(function () { if ($(window).scrollTop() > 100){ $(".c4").removeClass("hide"); }else { $(".c4").addClass("hide"); } }) $(".c4").click(function () { $(window).scrollTop(0) }) </script> </body> </html>