:root{--cerulean: #007BA7;--peacock: #005F6A;--indigo: #3F51B5;--teal: #009688;--white: #ffffff;--dark: #0f172a}body{margin:0;font-family:Poppins,sans-serif;background:linear-gradient(135deg,var(--cerulean),var(--peacock),var(--indigo),var(--teal));padding-top:70px;background-size:400% 400%;animation:gradientFlow 15s ease infinite;min-height:100vh;color:var(--white)}@keyframes gradientFlow{0%{background-position:0% 50%}50%{background-position:100% 50%}to{background-position:0% 50%}}.center{min-height:100vh;display:flex;flex-direction:column;justify-content:center;align-items:center;gap:16px;text-align:center;animation:fadeSlide 1.2s ease forwards}.center,.card{background:#ffffff1f;-webkit-backdrop-filter:blur(18px);backdrop-filter:blur(18px);border-radius:22px;padding:40px;box-shadow:0 25px 60px #00000040}h1{font-size:3rem;color:#e0f2ff;letter-spacing:1px;animation:floatText 3s ease-in-out infinite}h2{font-size:2rem;color:#dbeafe}h3{color:#c7d2fe}@keyframes 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0;animation:slideUp .4s ease forwards}.quiz-option:hover{background:linear-gradient(135deg,var(--teal),var(--indigo))}.result{font-size:2.5rem;color:#a7f3d0;animation:popIn .8s ease forwards}.review-card{background:#ffffff26;margin:12px;padding:20px;border-radius:18px;animation:fadeSlide .6s ease forwards}@keyframes fadeSlide{0%{opacity:0;transform:translateY(30px)}to{opacity:1;transform:translateY(0)}}@keyframes popIn{0%{transform:scale(.5);opacity:0}to{transform:scale(1);opacity:1}}@keyframes slideUp{0%{transform:translateY(40px);opacity:0}to{transform:translateY(0);opacity:1}}p{cursor:pointer;color:#bae6fd}p:hover{text-decoration:underline}@media(max-width:600px){h1{font-size:2.2rem}.center{padding:20px}}.timer{font-size:1.6rem;font-weight:700;padding:10px 22px;border-radius:14px;background:linear-gradient(135deg,#009688,#3f51b5);box-shadow:0 0 25px #0006}.correct{background:linear-gradient(135deg,#00c853,#1de9b6)!important;animation:pulse .6s 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(max-width:768px){.hamburger{display:block!important}}@media(max-width:768px){.nav-links{display:none;position:absolute;top:64px;right:16px;flex-direction:column;background:#000000e6;padding:16px;border-radius:16px;width:200px}.nav-links.show{display:flex}.hamburger{display:block}}.popup-overlay{position:fixed;inset:0;background:#000000b3;display:flex;align-items:center;justify-content:center;z-index:9999}.popup-box{width:90%;max-width:420px;background:#ffffff26;-webkit-backdrop-filter:blur(18px);backdrop-filter:blur(18px);padding:24px;border-radius:22px;color:#fff;position:relative;animation:popIn .4s ease;max-height:80vh;overflow-y:auto}.close-btn{position:absolute;top:14px;right:18px;font-size:22px;cursor:pointer}.popup-avatar{width:100px;border-radius:50%;margin:12px auto;display:block}.popup-card{background:#fff3;padding:14px;border-radius:14px;margin-top:10px}@keyframes popIn{0%{transform:scale(.8);opacity:0}to{transform:scale(1);opacity:1}}.modal-overlay{position:fixed;inset:0;background:#0009;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);display:flex;align-items:center;justify-content:center;z-index:1000}.modal{background:#4d737d;width:90%;max-width:650px;max-height:85vh;padding:22px;border-radius:16px;overflow-y:auto;animation:scaleIn .25s ease-in-out;box-shadow:0 25px 60px #00000059}@keyframes scaleIn{0%{transform:scale(.92);opacity:0}to{transform:scale(1);opacity:1}}.preview-question{background:#f9fafb;padding:14px 16px;border-radius:12px;margin-bottom:14px;border-left:4px solid #4f46e5}.preview-question p{margin:6px 0;font-size:15px;color:#111827;text-align:left}.preview-question ul{padding-left:20px;margin-top:8px;text-align:left}.preview-question li{margin-bottom:6px;color:#374151;text-align:left}.preview-question .timer{font-size:13px;color:#6b7280;margin-top:6px}.modal-actions{display:flex;justify-content:flex-end;gap:12px;margin-top:18px;border-top:1px solid #e5e7eb;padding-top:14px}@media(max-width:600px){.modal{width:95%;padding:16px}.preview-question{font-size:14px}}.leaderboard{width:100%;border-collapse:collapse;margin-top:15px}.leaderboard th,.leaderboard td{padding:10px;border-bottom:1px solid #ddd;text-align:center}.leaderboard tr.current-user{background-color:#fff3cd;font-weight:700}.leaderboard tr.current-user td{color:#856404}select{width:310px;padding:10px;border-radius:8px;border:1px solid #4f46e5;background-color:#eef2ff;color:#1e1b4b;font-size:14px;cursor:pointer}