/*-------------------------< Standartwerte überschreiben >-------------------------*/
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial;
}
/*-----------------------------------< body >--------------------------------------*/
body {
    display: flex;
    flex-direction: column;
    position: relative;
}
/*------------------------------------< head >-------------------------------------*/
.welcome {
    position: absolute;
    left: var(--h);
    top: var(--h);
}

header {
    position: sticky;
    top: 10px;
    background-color: rgb(128, 128, 128);
    display: flex;
    width: 50%;
    height: 60px;
    border-radius: var(--h);
    padding: 0;
    margin: 0 auto;
    margin-top: 10px;
    overflow: hidden;
}

header button {
    all: unset;
    flex: 1 1 0;
    display: flex;
    justify-content: center; 
    align-items: center;
    height: 100%;
}

button:hover {
    background-color: rgb(110, 110, 110);
}

header button p {
    display: flex;
    height: 80%;
    width: 50%;
    justify-content: center;
    align-items: center;
    box-shadow: inset 0 -0px 0 0 gold;
    transition: box-shadow 0.08s;
}

header button.active p {
    box-shadow: inset 0 -2px 0 0 gold;
}
/*------------------------------------< main >-------------------------------------*/
main {
    display: flex;
    background-color: black;
    width: 90%;
    min-width: 90%;
    margin-top: 20px;
    margin-bottom: 20px;
    align-self: center;
    min-height: 100dvh;
    height: 100dvh;
}

.seiten {
    display: none;
    width: 100%;
    height: 100%;
}

.main1 {
    background-color: green;
    display: flex;
}

.main2 {
    background-color: red;
}

.main3 {
    background-color: blue;
}
/*------------------------------------< foot >-------------------------------------*/
footer {
    position: relative;
    bottom: 0;
    background-color: lightgrey;
    width: 100%;
    display: flex;
    justify-content: space-evenly;
    padding: 20px;
}

footer ul {
    display: flex;
    flex-direction: column;
    border-left: 2px solid black;
}

footer ul li {
    list-style: none;
    margin: 10px;
}