*{
    margin:0;
    padding:0;
    box-sizing:border-box;
    font-family:Arial,Helvetica,sans-serif;
}

body{
    background:linear-gradient(135deg,#6a11cb,#2575fc);
    min-height:100vh;
    color:#fff;
}

header{
    text-align:center;
    padding:25px 15px;
}

header h1{
    font-size:2.2rem;
    margin-bottom:10px;
}

header p{
    font-size:1rem;
    opacity:0.9;
}

.container{
    width:95%;
    max-width:750px;
    margin:20px auto;
    background:#fff;
    color:#222;
    border-radius:20px;
    padding:25px;
    box-shadow:0 10px 30px rgba(0,0,0,.25);
}

#difficulty-screen{
    text-align:center;
}

#difficulty-screen h2{
    margin-bottom:25px;
}

.difficulty-btn{
    width:100%;
    padding:18px;
    margin:12px 0;
    border:none;
    border-radius:12px;
    font-size:18px;
    font-weight:bold;
    cursor:pointer;
    transition:.3s;
}

.difficulty-btn:hover{
    transform:scale(1.03);
}

.top-bar{
    display:flex;
    justify-content:space-between;
    flex-wrap:wrap;
    gap:10px;
    margin-bottom:20px;
    font-weight:bold;
}

#progress-container{
    width:100%;
    height:10px;
    background:#ddd;
    border-radius:50px;
    overflow:hidden;
    margin-bottom:25px;
}

#progress-bar{
    width:0%;
    height:100%;
    background:#28a745;
    transition:.4s;
}

.question{
    font-size:24px;
    font-weight:bold;
    margin-bottom:25px;
}

.answers{
    display:grid;
    gap:15px;
}

.answers button{
    padding:15px;
    border:none;
    border-radius:10px;
    background:#f1f1f1;
    color:#222;
    cursor:pointer;
    font-size:17px;
    transition:.3s;
}

.answers button:hover{
    background:#2575fc;
    color:#fff;
}

.correct{
    background:#28a745 !important;
    color:#fff !important;
}

.wrong{
    background:#dc3545 !important;
    color:#fff !important;
}

#next-btn{
    width:100%;
    margin-top:25px;
    padding:15px;
    border:none;
    border-radius:10px;
    background:#2575fc;
    color:#fff;
    font-size:18px;
    cursor:pointer;
}

#next-btn:hover{
    opacity:.9;
}

#result-screen{
    text-align:center;
}

#result-screen h2{
    margin-bottom:20px;
}

#result-screen button{
    padding:15px 30px;
    border:none;
    border-radius:10px;
    background:#28a745;
    color:#fff;
    font-size:18px;
    cursor:pointer;
}

footer{
    text-align:center;
    padding:25px;
    color:#fff;
    font-size:15px;
}

@media(max-width:600px){

header h1{
    font-size:1.8rem;
}

.question{
    font-size:20px;
}

.answers button{
    font-size:16px;
}

.top-bar{
    flex-direction:column;
    align-items:flex-start;
}

}