help with custom menu hover bar

Hello. I have been playing around with this CSS link hover. I can’t seem to figure out how to alter the code so that the items display horizontally instead of vertically:

CSS:

ul#menu2 {
    list-style-type: none;
    margin: 0;
    padding: 0;
    overflow: hidden;
    background-color: none;
}

ul#menu2  li a {
    position: relative;
    display: inline-block;
    color: white;
    text-align: left;
    padding: 9px 1px;
    text-decoration: none;
    font-size: 14px;
}

ul#menu2 li a::after {
	position: absolute;
	bottom: 150%;
	left: 0;
        width: 100%;
        height: 1px;
	background: #fff;
	content: '';
	opacity: 0;
	-webkit-transition: height 0.3s, opacity 0.3s, -webkit-transform 0.3s;
	-moz-transition: height 0.3s, opacity 0.3s, -moz-transform 0.3s;
	transition: height 0.3s, opacity 0.3s, transform 0.3s;
	-webkit-transform: translateY(-10px);
	-moz-transform: translateY(-10px);
	transform: translateY(-10px);
}

ul#menu2 li a:hover::after,
ul#menu2 li a:focus::after,
ul#menu2 li a:active::after {
	height: 5px;
	opacity: 1;
	-webkit-transform: translateY(0px);
	-moz-transform: translateY(0px);
	transform: translateY(0px);
}

HTML in code block:

<ul id="menu2">
  <li><a href="#home">born out of necessity</a></li>
  <li><a href="#news">identifying the need</a></li>
  <li><a href="#contact">implications</a></li>
  <li><a href="#about">breaking down user psychology</a></li>
  <li><a href="#about">research driven development</a></li>
  <li><a href="#about">survey and poll data</a></li>
</ul>

Do you think you guys can help make it so that the elements display in a horizontal line rather then on top of one another?