Embed Spreadshirt Shop in Main Menue

Site URL: https://www.balanceathletics.de/

Hello! 

I want to embed a Spreadshirt Shop in the main menue of my website www.balanceathletics.de - "Things for you"
I used the <code> thing to insert this:

<div id="myShop">
    <a href="https://shop.spreadshirt.de/balance-athletics-shop">balance-athletics-shop</a>
</div>

<script>
    var spread_shop_config = {
        shopName: 'balance-athletics-shop',
        locale: 'de_DE',
        prefix: 'https://shop.spreadshirt.de',
        baseId: 'myShop'
    };
</script>

<script type="text/javascript"
        src="https://shop.spreadshirt.de/shopfiles/shopclient/shopclient.nocache.js">
</script>

Since i have no idea what that means, i can't figure out what's wrong. The result is 

When I try with embed, this is the result

Can somebody help me? Thanks a lot!

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