How to create a drop down menu in HTML and CSS

copy and paste this code in your text editor to see the output.

Home
Company    

Introduction

our team

our clients


portfolio
our services
contact us

CSS code

#menu{
position:absolute;
top:150px;
left:8%;
padding:0;
margin:0;
}
#menu ul{
padding:0;
margin:0;
line-height:30px;
}
#menu li{
position:relative;
float:left;
list-style:none;
background:rgba(0,0,0,1);
border-radius:5px;
}
#menu ul ul{
position:absolute;
visibility:hidden;
padding:0;
margin:0;
top:30px;
}
#menu ul li a{
text-align:center;
font:"Arial Black", Arial;
font-size:24px;
color:rgba(255,255,255,9);
width:150px;
height:30px;
display:block;
text-decoration:none;
}
#menu ul li:hover{
background-color:rgba(128,128,128,1);
text-decoration:none;
}
#menu ul li:hover ul{
visibility:visible;
z-index:1;
}
#menu ul li:hover ul li a{
background:rgba(0,0,0,9);
z-index:1;
border-bottom:1px solid rgba(160,160,164,1);
opacity:0.9;
text-decoration:none;
border-radius:5px;
}
#menu ul li ul li:hover{
background:rgba(128,128,128,1);
opacity:0.8;
text-decoration:underline;
}