Dropdown menu not showing full text and text not aligned - html

Question

currently, my add subject, drop subject, delete subject, manual crawl in the submenu is not centralised even though i have specified it to be text-align center in #menu li li a. The sub menu's executive summary is also cut off. May I know how can i expand the submenu and centralise all my text?
Thank you!
Here is my code (i am really sorry because i do not have a jsfiddle acct and is on the waiting list):
HTML
<div id="menu">
<ul>
<li><a href="#" >Home</a></li>
<li><a href="#" >Executive Summary</a></li>
<li><a href="#" > Visual Analytics</a></li>
<li><a href="#" >Settings</a>
<ul>
<li>Add Subject</li>
<li>Delete Subject</li>
<li> Edit Subject</li>
<li><a href="#" >Manual Crawl</a></li>
<li><a href="#" >Executive Summary</a></li>
</ul>
</li>
</ul>
CSS
#menu {
position: relative;
float: left;
width: 1200px;
height: 35px;
font-family: Arial, Helvetica, sans-serif;
font-size: 13px;
padding: 0;
background: #000;
text-align: center;
}
#menu ul {
position: relative;
list-style: none;
display: inline-block;
margin: 0;
padding: 0;
}
#menu li {
position: relative;
float: left;
height: 100%;
padding: 0;
line-height: 35px;
}
#menu a {
position: relative;
height: 100%;
width: auto;
float: left;
text-decoration: none;
padding: 0 0 0 25px;
margin: 0 3px;
color: #fff;
text-align: center;
}
#menu ul ul {
display: none;
width: 10em; /* Width to help Opera out */
background-color: rgba(0,0,0,0.5);
}
#menu li:hover ul {
display:block;
position: absolute;
top: 35px;
left: 0;
margin: 0;
padding: 0;
z-index: 1;
}
#menu li li a{
height: 35px;
width: 100%;
float: left;
text-decoration: none;
padding: 0 0 0 25px;
margin: 0 3px;
color: #fff;
text-align: center;
}
#menu li li a:hover{
background: rgba(255,255,255,0.5);
}

Answer 1

#menu {
position: relative;
float: left;
width: 1200px;
height: 35px;
font-family: Arial, Helvetica, sans-serif;
font-size: 13px;
padding: 0;
background: #000;
text-align: center;
}
#menu ul {
position: relative;
list-style: none;
display: inline-block;
margin: 0;
padding: 0;
}
#menu li {
position: relative;
float: left;
height: 100%;
padding: 0;
line-height: 35px;
}
#menu a {
position: relative;
height: 100%;
width: auto;
float: left;
text-decoration: none;
padding: 0px 10px 0px 10px;
margin: 0 3px;
color: #fff;
text-align: center;
}
#menu ul ul {
display: none;
width: 11em; /* Width to help Opera out */
background-color: rgba(0,0,0,0.5);
}
#menu li:hover ul {
display:block;
position: absolute;
top: 35px;
left: 0;
margin: 0;
padding: 0;
z-index: 1;
}
#menu li li a{
height: 35px;
width: 100%;
float: left;
text-decoration: none;
padding: 0px 10px 0px 10px;
margin: 0 0px;
color: #fff;
text-align: center;
}
#menu li li a:hover{
background: rgba(255,255,255,0.5);
}

Answer 2

add styling
#menu li li a{
height: 35px;
width: 100%;
float: left;
text-decoration: none;
padding: 0 13px;
margin: 0 3px;
display: block;
color: #fff;
text-align: center;
}
Your <a> having only left padding but it has to be from both right-left or you could remove padding