Edit in JSFiddle

/*
Techonolgy Quest;

creating a horizontal menu is simple.

Following id will define the dimensions for the menu, margin, padding width, height.
*/

#menucontainer {
    margin: 0px;
    padding: 0px;
    width: 100%;
    height: 90px;
}

#menucontainer ul, #menucontainer li, #menucontainer a {
    margin: 0px;
    padding: 0px;
}
/* Following selectors will define the color and the border radius for the menu*/
#menucontainer ul, #menucontainer li {
    list-style: none;
    background-color:#2CDF7B;
    /*Using the border-radius property from css3 to get rounded corners for the menu */
    -moz-border-radius: 20px;
    -webkit-border-radius: 20px;
    -khtml-border-radius: 20px;
    border-radius: 20px;
}
/* Following selector will define the style for individual menu or li tags. The following style gives them a look when the menus are not selected.
note that the position proerty is set to relative and dispaly is inline.
*/
#menucontainer ul li {
    list-style: none;
    margin: 0px;
    padding: 0px;
    background-color:#2CDF7B;
    position: relative;
    display: inline;
    width: auto;
    height: 70px;
}
/* Style for the anchor tag defined in the menu. 
*/
#menucontainer ul li a {
    list-style: none;
    margin-left: 10px;
    padding-left: 10px;
    margin-right: 10px;
    padding-right: 10px;
    background-color:transparent;
    position: relative;
    display: inline;
    text-decoration: none;
    font-family:"Times New Roman", "Arabic";
    font-size: 20px;
    color: #E3E3C0;
}
/* The hover effect is defined using the below selectors
For the background-color the function rgba is used to create a semi-transperant look as a hover effect
*/

#menucontainer ul li:hover {
    list-style: none;
    margin: 0px;
    padding: 0px;
    background-color:rgba(195, 190, 95, 0.6);
    position: relative;
    display: inline;
    -moz-border-radius: 20px;
    -webkit-border-radius: 20px;
    -khtml-border-radius: 20px;
    border-radius: 20px;
}
#menucontainer ul li:hover a {
    list-style: none;
    margin-left: 10px;
    padding-left: 10px;
    margin-right: 10px;
    padding-right: 10px;
    background-color:transparent;
    position: relative;
    display: inline;
    text-decoration: none;
    font-family:"Times New Roman", "Arabic";
    font-size: 20px;
    color:white;
    z-index: 20;
}