body {
    background-color: rgb(15, 15, 15);
    font-family: Ubuntu, Arial;
    color: white;
}

#header {

    position: fixed;
    top: 0;
    left: 0;

    width: 100vw;
    height: 3em;

    background-color: rgb(10, 10, 10);
    border-bottom: 1px inset rgb(255,200,200);

    display: flex;
    align-items: center;
    justify-content: center;

}

.header-button {
    transition: background-color 0.25s;
    border: none;
    color: white;
    background-color: rgb(10,10,10);
    height: 100%;
    flex: 1;
}

.header-button:hover {
    transition: background-color 0.25s;
    background-color: rgb(25,25,25);
}