*{
    margin:0;
    padding:0;
    box-sizing:border-box;
}
body{
    font-family:'Poppins',sans-serif;
    background:linear-gradient(135deg,#07142b,#091d45,#000814);
    color:#fff;
    min-height:100vh;
}
.container{
    display:grid;
    grid-template-columns:2fr 1fr;
    gap:25px;
    padding:30px;
    max-width:1400px;
    margin:auto;
}
.left{
    display:flex;
    flex-direction:column;
    gap:20px;
}
.right{
    background:rgba(255,255,255,.06);
    backdrop-filter:blur(12px);
    border-radius:18px;
    padding:25px;
    border:1px solid rgba(255,255,255,.15);
}
.topbar{
    display:flex;
    justify-content:space-between;
    align-items:center;
}
#timer{
    width:75px;
    height:75px;
    border-radius:50%;
    display:flex;
    justify-content:center;
    align-items:center;
    background:#ff9800;
    color:#fff;
    font-size:28px;
    font-weight:bold;
    box-shadow:0 0 20px rgba(255,152,0,.5);
}
#questionBox{
    background:rgba(255,255,255,.08);
    border-radius:18px;
    padding:35px;
    min-height:160px;
    display:flex;
    align-items:center;
    justify-content:center;
    text-align:center;
    font-size:24px;
    border:1px solid rgba(255,255,255,.15);
}
.options{
    display:grid;
    grid-template-columns:1fr 1fr;
    gap:18px;
}
.option{
    padding:18px;
    border:none;
    border-radius:14px;
    background:#173d8f;
    color:#fff;
    font-size:18px;
    cursor:pointer;
    transition:.25s;
}
.option:hover{
    background:#2459c7;
    transform:translateY(-2px);
}
.option.selected{
    background:#ff9800;
}
.option.correct{
    background:#00c853;
}
.option.wrong{
    background:#d50000;
}
.option:disabled{
    cursor:not-allowed;
    opacity:.75;
}
.buttons{
    display:flex;
    gap:15px;
}
.buttons button{
    flex:1;
}
button{
    padding:15px;
    border:none;
    border-radius:12px;
    background:#1565c0;
    color:white;
    font-size:17px;
    cursor:pointer;
    transition:.25s;
}
button:hover{
    background:#1e88e5;
}
button:disabled{
    opacity:.5;
    cursor:not-allowed;
}
#explanation{
    background:rgba(255,255,255,.08);
    padding:20px;
    border-radius:15px;
    display:none;
    line-height:1.7;
}
.right h2{
    margin-bottom:15px;
}
#ladder{
    list-style:none;
}
#ladder li{
    padding:12px;
    margin-bottom:8px;
    border-radius:10px;
    background:rgba(255,255,255,.08);
    transition:.25s;
}
#ladder li.active{
    background:#ff9800;
    color:#000;
    font-weight:bold;
}
.right hr{
    margin:25px 0;
    border:none;
    border-top:1px solid rgba(255,255,255,.2);
}
.right button{
    width:100%;
    margin-bottom:12px;
}
.overlay{
    position:fixed;
    inset:0;
    background:rgba(0,0,0,.85);
    display:flex;
    justify-content:center;
    align-items:center;
    z-index:1000;
}
.card{
    background:#112d62;
    padding:40px;
    border-radius:18px;
    width:90%;
    max-width:520px;
    text-align:center;
    box-shadow:0 0 30px rgba(0,0,0,.45);
}
.card h1{
    margin-bottom:15px;
}
.card p{
    margin-bottom:25px;
    line-height:1.7;
}
#finalScore{
    margin:20px 0;
    font-size:30px;
    color:#ffeb3b;
}
@media(max-width:900px){
.container{
    grid-template-columns:1fr;
}
.options{
    grid-template-columns:1fr;
}
#questionBox{
    font-size:20px;
}
#timer{
    width:60px;
    height:60px;
    font-size:22px;
}
}