body {
    margin: 0px;
    background-color: darkgray;
}

.menu-lewy, .menu-prawy {
    float: left;
    border-bottom: 1px solid black;
    height: 200px;
    background-color: gray;
}

.menu-lewy {
    width: 70%;
    text-align: center;
    color: white;
}

.menu-lewy h1 {
    margin-top: 70px;
    font-size: 64px;
}

.menu-prawy {
    width: 30%;
    justify-content: left;
}

.content {
    clear: both;
    width: 400px;
    height: 400px;
    transform: translate(-50%, -50%);
    position: absolute;
    left: 50%;
    top: 50%;
    border: 1.5px solid black;
    border-radius: 50px;
    background-color: gray;
}

.content form {
    text-align: center;
    margin-top: 15%;
    color: white;
}

.content h3 {
    color: white;
    text-align: center;
}

.start {
    margin-top: 12%;
    padding: 25px;
    border-radius: 25px;
    transition: 0.5s;
}

.start:hover {
    background-color: darkgray;
    transition: 0.5s;
}

.next {
    padding: 10px;
    border-radius: 15px;
    transition: 0.5s;
}

.next:hover {
    background-color: darkgray;
    transition: 0.5s;
}

.content span {
    font-size: 20px;
}