Mobile Resposivebility

I’am trying to make a mobile responsive website but when i use z-index and position so that my burger menu is on top of everything the menu is a little down any help
Code:
HTML:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <link rel="icon" type="image/png" href="/favicon.png" sizes="16x16" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="style.css">
    <link href="https://fonts.googleapis.com/css?family=IBM+Plex+Sans&display=swap" rel="stylesheet">
    <title>GemPvP</title>
</head>

<body background="testbg.png" text="white"></body>

<body>
<div class="site-wrapper">

    <div class="backgroundSwitch">
        <body background="" text="white"></body>
    </div>

    <center>
    <div class="logo">
        <img src="" height="300" width="300">
    </div>
    </center>
    <br>

    <div class="server-ip">
    <span class="p-header-playNow-hostname-prefix">Server IP » </span>
    <span class="p-header-playNow-hostname-copy" data-clipboard-text="gempvp.ga">GemPvP.GA</span>
    </div>

    <br>

    <nav>
        <ul class="nav-links">
            <li><a href="index.html">Home</a></li>
            <li><a href="forums.php">Forums</a></li>
            <li><a href="games.html">Games</a></li>
            <li><a href="rules.html">Rules</a></li>
            <li><a href="http://gempvpstore.buycraft.net/" target="blank">Store</a></li>
        </ul>
        <div class="burger">
            <div class="line1"></div>
            <div class="line2"></div>
            <div class="line3"></div>
        </div>
    </nav>

CSS:

* {
    margin: 0px;
    padding: 0px;
    box-sizing: border-box;
    font-family: 'IBM Plex Sans', sans-serif;
}

nav{
    border-radius: 25px;
    width: 50%;
    margin: 0 auto;
    display: inline-block;
    display: flex;
    justify-content: space-around;
    align-items: center;
    min-height: 8vh;
    background-color: #1CE91F;
    background-image: none;
}

.nav-links{
    display: flex;
    background-image: none;
    justify-content: space-around;
    width: 100%;
}
.nav-links li{
    list-style: none;
}
.nav-links a{
    color: rgb(0, 0, 0);
    text-decoration: none;
    font-weight: bold;
    text-transform: uppercase;
}

.burger{
    display: none;
}
.welcome{
    max-width: 100%;
    margin-left: 30%;
    position: absolute;
}

.burger div{
    width: 25px;
    height: 3px;
    background-color: rgba(255, 255, 255, 0.925);
    margin: 5px;
    transition: all 0.3s ease;
}

.server-ip{
    width: 100%;
    text-align: center;
    color: yellowgreen;
}
.logo{
    width: 100%;
    align-content: center;
}

@media screen and (max-width:1024px){
    .nav-links{
        width: 80%;
    }
}

@media screen and (max-width:768px){
    body{
        overflow-x: hidden;
    }
    .welcome{
        max-width: 100%;
        margin:  auto;
    }
    
    .nav-links{
        width: 100%;
        position: absolute;
        right: 0px;
        height: 86vh;
        top: 14.25vh;
        background-color: #1CE91F;
        display: flex;
        flex-direction: column;
        align-items: center;
        transform: translateX(100%);
        transition: transform 0.5s ease-in;
    }
    .nav-links li{
        opacity: 0;
    }
    .burger{
        cursor: pointer;
        display: block;
    }
    .logo{
        display: none;
    }
    nav{
        nav-index: 1;
        z-index: 1;
        position: relative;
        height: 100%;
        width: 100%;
        background-color: #1CE91F;
        border-radius: 0px;
    }

}

.nav-active{
    transform: translateX(0%);
}

@keyframes navLinkFade{
    from{
        opacity: 0;
        transform: translateX(50px);
    }
    to{
        opacity: 1;
        transform: translateX(0px);
    }
}

.toggle .line1{
    transform: rotate(-45deg) translate(-5px,6px);
}
.toggle .line2{
    opacity: 0;
}
.toggle .line3{
    transform: rotate(45deg) translate(-5px,-6px);
}


.logo img{
    max-width: 100%;
}

Any help?