源码：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style type="text/css">
html, body {
margin: 0px;
padding: 0px;
width: 100%;
height: 100%;
font-family: "微软雅黑";
font-size: 62.5%;
}
.boxDom {
width: 100%;
height: 100%;
position: relative;
overflow: hidden;
}
.idDom {
width: 100%;
height: 100px;
background: #666;
position: fixed;
bottom: 0px;
}
.content {
display: inline-block;
width: 430px;
height: 40px;
position: absolute;
left: 0px;
right: 0px;
top: 0px;
bottom: 0px;
margin: auto;
}
.title {
display: inline;
font-size: 4em;
vertical-align: bottom;
color: #fff;
}
.text {
border: none;
width: 300px;
height: 30px;
border-radius: 5px;
font-size: 2.4em;
}
.btn {
width: 60px;
height: 30px;
background: #f90000;
border: none;
color: #fff;
font-size: 2.4em;
}
span {
width: 300px;
height: 40px;
position: absolute;
overflow: hidden;
color: #000;
font-size: 4em;
line-height: 1.5em;
cursor: pointer;
white-space: nowrap;
}
</style>
</head>
<body>
<div class="boxDom" id="boxDom">
<div class="idDom" id="idDom">
<div class="content">
<p class="title">吐槽:</p>
<input type="text" class="text" id="text" />
<button type="button" class="btn" id="btn">发射</button>
</div>
</div>
</div>
<script src=" js/jquery-3.3.1.js"></script>
<script>
$(function(){
var colors = ["red", "green", "blue", "pink", "yellow", "cyan", "purple"];
$("#btn").click(function(){
var randomColor = parseInt(Math.random() * colors.length);//随机选择一个颜色
var randomY = parseInt(Math.random() * 400);//随机一个Y轴位置
//创建span并设置内容
$("<span></span>").text($("#text").val())
.css("color",colors[randomColor])
.css("left","2000px")
.css("top",randomY)
.animate({left:-500},10000,function(){
$(this).remove();
})
.appendTo("#boxDom");
$("#text").val("");
});
//回车键按下时调用发送按钮的click事件发送信息，设置回车键发送
$("#text").keyup(function (e) {
if (e.keyCode == 13) {
$("#btn").click();
}
});
});
</script>
</body>
</html>
效果图：
