*{
    padding: 0;
    margin: 0;
    box-sizing: 0;
    
}
body{
    background: #001e4d;
}
.app{
    background: white;
    width: 90%;
    max-width: 600px;
    margin: 100px auto 0;
    border-radius: 10px;
    padding: 30px;

}
.app h1{
    font-size: 25px;
    color: #001e4d;
    font-weight: 600;
    border-bottom: 1px solid#333;
    padding-bottom: 30px;
}
.quiz{
    padding: 20px 0px;
    }
    .quiz h2{
        font-size: 18px;
        color: #001e4d;
        font-weight: 600;
    }
    .btn{
        background: white;
        color: #222;
        font-weight: 500;
        width: 100%;
        border: 1px solid #222;
        padding: 10px;
        margin: 10px 0;
        text-align: left;
        border-radius: 4px;
        cursor: pointer;
        transition: all 0.3s;
    }
    .btn:hover{
        background-color: #222;
        color: white;

    }
    #next-btn{
        background: #001e4d;
        color: white;
        font-weight: 500;
        width: 150px;
        border: 0;
        padding: 10px;
        margin: 20px auto 0;
        border-radius: 4px;
        cursor: pointer;
        display: none;
    }
    .btn.correct {
     border: 5px solid green;
      color: aliceblue;
      background-color: #333;
      font-weight: 800;
      box-shadow:  5px 5px 5px green;
    }
    
    .btn.wrong {
 border: 5px solid red;
 background-color: #333;
        color: white;
        font-weight: 800;
    }
    
    .btn {
        margin: 5px;
        padding: 10px 20px;
        cursor: pointer;
        border: none;
        border-radius: 5px;
        font-size: 16px;
    }
    
    #next-btn {
        margin-top: 20px;
        padding: 10px 20px;
        font-size: 16px;
        cursor: pointer;
    }
 #mainHeading{
    font-weight: 700;
    display: flex;
    justify-content: center;
    align-content: center;
    color: hsl(217, 100%, 15%);
    font-size: 50px;
 }
 #question{
    font-size: 25px;
 }