:root{--primary:#0b5cff;--muted:#6b7280;--bg:#f6f8fb}
*{box-sizing:border-box}
body{font-family:Inter,system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;margin:0;background:var(--bg);color:#111}
.wrap{max-width:980px;margin:0 auto;padding:18px}
.site-header{background:#fff;border-bottom:1px solid #eef2f7}
.site-header .wrap{display:flex;align-items:center;justify-content:space-between}
.brand{font-weight:700;color:var(--primary);text-decoration:none;font-size:20px}
.nav a{margin-left:14px;color:#374151;text-decoration:none}
.btn{background:var(--primary);color:#fff;padding:8px 12px;border-radius:8px;text-decoration:none}
.site-footer{background:#fff;border-top:1px solid #eef2f7;margin-top:20px}
.card{background:#fff;padding:18px;border-radius:12px;box-shadow:0 6px 18px rgba(12,15,22,.04);margin:16px 0}
h1,h2{margin:0 0 12px}
input[type=text],input[type=email],input[type=password],select,textarea{width:100%;padding:10px;border:1px solid #e5e7eb;border-radius:8px;margin:6px 0}
.question{padding:12px;border-radius:8px;border:1px solid #eef2f7;margin:12px 0}
.option{display:block;margin:6px 0;padding:8px;border-radius:8px;border:1px solid #e6eefc;cursor:pointer}
.timer{font-weight:700;color:var(--primary)}
.progress{height:10px;background:#e6eefc;border-radius:999px;overflow:hidden}
.progress > span{display:block;height:10px;background:var(--primary);width:0}
.leaderboard li{padding:8px 0;border-bottom:1px dashed #f1f5f9}
.small-muted{color:var(--muted);font-size:13px}
@media(max-width:640px){.wrap{padding:12px}.site-header .wrap{flex-direction:column;align-items:flex-start}}