JS events

<style type="text/css">
	#with{
		width: 1200px;
		height: 1000px;
		background-color: white;
	}
	
	
	.something{
		width: 1000px;
		height: 100px;
		background-color:aqua;
	}
	.two{
		width: 1000px;
		height: 50px;
		background-color:aliceblue;
	}
	.two1{
		width: 1000px;
		height: 150px;
		background-color:red;
	}
	.two2{
		width: 1000px;
		height: 50px;
		background-color:white;
	}
	#three{
		width: 1000px;
		height: 50px;
		background-color:aquamarine;
	}
	#four{
		width: 1000px;
		height: 50px;
		background-color:blueviolet;
	}
	#four1{
		width: 100px;
		height: 20px;
		background-color: aliceblue;
		border-radius: 25px;
		text-align: center;
		
	}
	#four2{
		width: 100px;
		height: 20px;
		background-color: aliceblue;
		border-radius: 25px;
		text-align: center;
		display: none;
		
	}
	#five{
		width: 1000px;
		height: 50px;
		background-color:chartreuse;
	}
	#sex{
		width: 1000px;
		height: 50px;
		background-color:burlywood;
	}
	#sex1{
		width: 300px;
		height: 100px;
		border: 1px solid black;
		border-radius: 25px;
		
		
	}
	#r{
		width: 1000px;
		height: 50px;
		background-color:fuchsia;
	}
	#pop{
		background-color: aliceblue;
	}
	

　　 <!--当点击下面的div时，弹出窗口-->

<div class="noe">Describe event
<input type="button" name="" id="" value="按钮" onClick="aa()">
</div>   

　function aa(){
   alert("弹窗");
   }

　 <!--当鼠标移到下面的div时，显示按钮，当移出时，按钮消失-->

<div id="five">
	<span calss="five1" onMouseMove="f()" onMouseOut="g()">今天有风</span>
	<span class="fivee" style="display: none" >今天没风</span>
</div>



//f method, when the mouse moves in, the content is displayed
function f(){
var fivee = document.getElementsByClassName("fivee")[0];
	fivee.style.display = "block";
}


function g(){
	var fivee = document.getElementsByClassName("fivee")[0];
	fivee.style.display = "none";
}

　　<!--Through an if judgment, it is judged that when the display is hidden, it is set to be displayed, and when it is displayed, it is set to be hidden -->

<div id="r">
	<div id="po" onClick="ss()">Dong brother my male god</div>
	<div id="pop" style="display: none">没错</div>
</div>

with ==
var a = document.getElementById("pop");
	if(a.style.display == "none"){
		a.style.display = "block";
	}else{a.style.display = "none";
		
	}
}