My :hover doesn't work properly, When i hover over the h2's it doesn't underline the h2

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h1 {
text-align:center;
margin-top: 50px;
font-family: "Garamond", serif;

}

h2 {
text-align:center;
margin-top: 0px;
font-size: 15px;
font-family: "Garamond", serif;
}

.center {
display: block;
margin-left: auto;
margin-right: auto;
margin-top: 80px;
float:middle;
}

header > h2 {
color: #2D52A0;
font-family: "Arial", sans-serif;
}

header > h2:hover {
text-decoration: underline;
}

.English {
position: relative;
bottom: 250px;
right: 120px;

}

.Spanish {
position: relative;
top: -280px;
left: 120px;
}

.Japanese {
position: relative;
top: -250px;
right: 180px;
}

.Deutsch {
position: relative;
top: -280px;
left: 180px;
}

.Russian {
position: relative;
top: -250px;
right: 200px;
}

.French {
position: relative;
top: -280px;
left: 200px;
}

.Italian {
position: relative;
top: -250px;
right: 180px;
}

.Chinese {
position: relative;
top: -280px;
left: 180px;
}

.Portugese {
position: relative;
top: -250px;
right: 120px;
}

.Polski {
position: relative;
top: -280px;
left: 120px;
}

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English
Español
日本語
Deutsch
Русский
Francais
Italiano
中文
Portugues
Polski