styles.css

:root{

    --background-landing:linear-gradient(to right, hsl(13, 100%, 72%),hsl(353, 100%, 62%));

    --background-mobile-panel:#ffff;

    --font-family-primary:'Ubuntu',san-serif;
    --font-family-secondary:'Overpass',san-serif;

    --font-size-u1:400;
    --font-size-u2:500;
    --font-size-u3:700;

    --font-size-o1:300;
    --font-size-o2:600;

    --primary-color:rgb(224, 212, 212);
    --mobile-nav:rgb(75, 69, 69);
    /* --mobile-nav:#ffff; */
}

*,*::before,*::after{
    box-sizing: border-box;
}

body{
    font-weight: 16px;
    margin: 0px,0px;
    width: 100%;
}
header{
    background: var(--background-landing);
    text-align: left;
    position: fixed;
    width: 100%;
    z-index: 999;
    padding:1em;
    margin: -10px -10px -10px -10px;
}

.logo{
    color: #fff;
    font-family: var(--font-family-primary);
    font-weight: var(--font-size-u3);
    font-size:2em;
}

nav{
    display: flex;
    background: var(--background-mobile-panel);
    justify-content: center;
    align-items: center;
    width:70%;
    position:relative;
    text-align:center;
    top: 100%;
    left: 15%;
}

nav ul{
    list-style: none;
    margin: 0;
    padding: 0;
    list-style: none;
}

nav li{
    margin-bottom: 1em;
    margin-left: 1em;
    margin-top: 1em;
}

nav a{
    color:var(--mobile-nav);
    font-weight: var(--font-size-u2);
    font-family: var(--font-family-primary);
    font-size: 1.1rem;
    text-decoration: none;
    text-size-adjust: 2em;
    display: block;
}

.shutter-pannel{
    border-radius: 10px;
}
.auth{
    padding: 0.5rem;
    border-radius: 20px;
}
.active{
    background:var(--background-landing);
}

.nav-toggle{
    float: right;
    margin-left: 95%;
}

.nav-toggle:checked ~ nav {
    display:block;
}