* {
    margin: 0;
    padding: 0;
    font-family: "Berkeley";
    box-sizing: border-box;
    font-weight: bold;
}

body {
    background: black;
}

.app {
    background: white;
    width: 50%;
    max-width: 600px;
    margin: 10px auto 0;
    border-radius: 10px;
    margin: 50px auto 0;
    padding: 10px;
}

.app h1 {
    font-size: 35px;
    color: black;
    font-weight: 600;
    border-bottom: 1px solid grey;
    padding-bottom: 15px;
}
.quiz {
    padding: 10px 0;
}

.quiz h2 {
    font-size: 23px;
    color: black;
    font-weight: 600;
}

.btn {
    font-size: 27px;
    background: white;
    color: black;
    font-weight: 1000;
    width: 100%;
    border: 2px solid grey;
    padding: 10px;
    margin: 10px 0;
    text-align: left;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.btn:hover:not([disabled]) {
    background: lightgrey;
    color: black;
}

.btn:disabled {
    cursor: no-drop;
}
#next-btn {
    font-size: 25px;
    background: lightgrey;
    color: black;
    font-weight: 500;
    width: 150px;
    border: solid black 2px;
    padding: 10px;
    margin: 20px auto 0;
    border-radius: 4px;
    cursor: pointer;
    display: none;
}

.correct {
    background: green;
}

.incorrect {
    background: red;
}

button {
    padding: 7px;
    margin: 7px;
    border-radius: 5px;
    cursor: pointer;
}

.buttons {
    margin-top: 10px;
    margin-bottom: 10px;
    margin-left: 200px;
    margin-right: 200px;
    padding: 10px;
}