<style>

ul.arrowunderline{
list-style-type:none;
margin:0;
padding:0;
text-align:center; /* enter "left", "right", or "center" to orient the menu accordingly */
font: bold 16px Georgia;
}

ul.arrowunderline li{
display:inline;
margin-right:25px; /* spacing between each menu item */
}

ul.arrowunderline li a{
position:relative;
color:black;
padding-bottom:8px; /*spacing between each menu item and arrow underline beneath it */
text-decoration:none;

}

ul.arrowunderline li a:hover{
border-bottom:3px solid purple; /* style of arrow underline */
}

ul.arrowunderline li a:hover:after{ /* use CSS generated content to add arrow to the menu */
content:'';
width:0;
height:0;
position:absolute;
left:50%;
margin-left:-5px; /* value should match border-width below */
bottom: 0;
border-width:5px; /* value should match margin-left above */
border-style:solid;
border-color: transparent transparent purple transparent; /* create up arrow */
}

</style>
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