Unable to position text

I center-aligned some text and then positioned it using top:20%. It worked fine, but when I added a paragraph under it, the element just moved back into the beginning position(the top:20% didn't take effect).

    <style>
    .yes{
            width : 100%;
            height : 50%;
            background-color: red;
            text-align: center;
        }
        .yes a{
            font-size : 300%;
            position: relative;
            top : 20%;
        }
    </style>

    <div class = "yes">
    <a>Title</a>
    <p></p></div>