&{
   margin: 0;
   padding: 0;
   font-family: 'Poppins', sans-serif;
   box-sizing: border-box;
}

body{
   background: #001e4d;
}

.app{
   background-color: #fff;
   width: 90%;
   max-width: 600px;
   margin: 100px auto 0;
   border-radius: 10px;
   padding: 30px;
}  

.app h1{
   font-size: 24px;
   color: #001e4d;
   border-bottom: 1px solid #333;
   padding-bottom: 30px;
}

.quiz{
   padding: 20px 0px;
}

.quiz h2{
   font-size: 18px;
   color: #001e4d;
   font-weight: 600;
}

.btn{
   background: #fff;
   color: #222;
   font-weight: 500;
   width: 100%;
   border: 1px solid #222;
   padding: 10px;
   margin: 10px 0px;
   text-align: left;
   border-radius: 4px;
   cursor: pointer;
   transition: 0.2s ease;
}

.btn:hover:not([disabled]){
   background: #222;
   color: #fff;
}

.btn:disabled{
   cursor: no-drop;
}
#next-btn{
   background-color: #001e4d;
   color: #fff;
   font-weight: 500;
   width: 150px;
   border: 0;
   padding: 10px;
   margin: 20px auto 0;
   border-radius: 4px;
   cursor: pointer;
   display: none;
}

.correct{
   background-color: #9aeabc;
}

.incorrect{
   background-color: #ff9393;
}