header{
    padding: 10px 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}
.header_text{
    width: 850px;
}
.circle{
    height:70px;
    width:220px;
    max-height: 60vw;
    max-width: 50vw;
    overflow: hidden;
    border-radius: 50%;
    border: 5px solid var(--kreis-color);
    display: flex;
    justify-content: center;
    align-items: center;
}
.circle img{
    width: 100%;
}
nav{
    margin: bottom 100px;
}
nav ul{
    list-style: none;
    display: flex;
    gap: 20px;
}
nav a{
    color: var(--secondary-text-color);
    text-decoration: none;
    position: relative;
    padding: 3px;
}
nav a:hover{
    color: var(--text-color);
}

nav a::after{
    content: '';
    height: 2px;
    width: 0;
    background: var(--main-brand-color);
    position: absolute;
    bottom: 0;
    left: 0;
    transition: 150ms ease-in-out;
}
nav a:hover::after{
    width: 100%;
}
#toggle_button{
    display: none;
}label[for="toggle_button"]{
    display: none;
}
label[for="toggle_button"] span{
    font-size: 40px;
}
@media(max-width:800px){
  nav{
    position: absolute;
    top: 0;
    left: 0;
    background:var(--secondary-color);
    padding: 15px;
    border-radius: 0 0 25px 0;
  }
    nav ul{
        display: none;
        flex-direction: column;
    }
#toggle_button:checked ~ul{
display: flex;
}
label[for="toggle_button"]{
    display: block;
    }
}