*{margin:0;padding:0;box-sizing:border-box}:root{--primary-color: #1e90ff;--primary-glow: rgba(30, 144, 255, .5);--secondary-color: #ffd700;--bg-dark: #0a0a2e;--bg-darker: #050515;--text-color: #ffffff;--text-secondary: #b0b0b0;--success-color: #00ff88;--error-color: #ff4444;--answer-bg: linear-gradient(135deg, #1a1a4e 0%, #0d0d2b 100%);--answer-border: #3a3a8a;--answer-hover: linear-gradient(135deg, #2a2a6e 0%, #1a1a4b 100%)}.theme-gold{--primary-color: #ffd700;--primary-glow: rgba(255, 215, 0, .5);--secondary-color: #ff8c00}.theme-cosmic{--primary-color: #9b59b6;--primary-glow: rgba(155, 89, 182, .5);--secondary-color: #e74c3c;--bg-dark: #0f0f23;--bg-darker: #050510}.theme-neon{--primary-color: #00ff88;--primary-glow: rgba(0, 255, 136, .5);--secondary-color: #ff00ff;--bg-dark: #0a0a1a}.bg-sunset{background:radial-gradient(ellipse at center bottom,#ff6b35,#f7931e 20%,#9b2335 50%,#1a0a1e)!important}.bg-ocean{background:radial-gradient(ellipse at center,#0077b6,#023e8a,#03045e 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span{font-weight:700}.game-container{flex:1;display:flex;flex-direction:column;padding:20px}.game-header{display:flex;justify-content:space-between;align-items:center;padding:20px;background:#00000080;border-radius:15px;margin-bottom:30px;border:1px solid var(--primary-color)}.timer-container{display:flex;align-items:center;gap:15px}.timer-bar{width:200px;height:20px;background:#ffffff1a;border-radius:10px;overflow:hidden;border:1px solid var(--primary-color)}.timer-fill{height:100%;background:linear-gradient(90deg,var(--success-color),var(--primary-color));transition:width .1s linear;border-radius:10px}.timer-fill.warning{background:linear-gradient(90deg,#f80,#f40)}.timer-fill.danger{background:linear-gradient(90deg,var(--error-color),#cc0000);animation:pulse .5s ease-in-out infinite}@keyframes 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rgba(255,255,255,.1)}.explanation-title{font-size:1.1rem;color:var(--primary-color);margin-bottom:15px;text-transform:uppercase;letter-spacing:1px}.explanation-body{font-size:1.05rem;line-height:1.8;color:var(--text-color)}.explanation-body .formula{display:block;background:#1e90ff26;border-left:3px solid var(--primary-color);padding:12px 15px;margin:15px 0;font-family:Courier New,monospace;font-size:1.2rem;color:var(--secondary-color);border-radius:0 8px 8px 0}.explanation-body .highlight{color:var(--secondary-color);font-weight:700}.explanation-body .example{display:block;background:#9b59b626;border-left:3px solid #9b59b6;padding:10px 15px;margin:12px 0;font-style:italic;border-radius:0 8px 8px 0}.explanation-text{font-size:1.1rem;line-height:1.6;color:var(--text-secondary);margin-bottom:30px;text-align:left;padding:20px;background:#0000004d;border-radius:10px}.podcast-listen-btn{display:flex;align-items:center;justify-content:center;gap:8px;width:100%;margin-bottom:10px;background:linear-gradient(135deg,#1e90ff33,#ffd70026);border:2px solid var(--secondary-color);color:var(--secondary-color);font-weight:700;padding:12px 20px;border-radius:12px;cursor:pointer;transition:all .2s;font-size:1rem}.podcast-listen-btn:hover{background:linear-gradient(135deg,#1e90ff59,#ffd70040);transform:scale(1.02);box-shadow:0 0 15px #ffd7004d}.learn-toast{position:fixed;top:20px;right:20px;z-index:150;max-width:420px;width:calc(100% - 40px);transform:translate(calc(100% + 30px));transition:transform .4s 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#1e90ff26}.learn-toast-robot{font-family:Courier New,monospace;font-size:1.4rem;color:var(--secondary-color);flex-shrink:0;width:48px;text-align:center;animation:robot-bounce .6s ease-in-out infinite alternate}@keyframes robot-bounce{0%{transform:translateY(0)}to{transform:translateY(-4px)}}.learn-toast-loading-info{flex:1;min-width:0}.learn-toast-loading-text{font-size:.8rem;color:var(--text-color);margin:0 0 6px}.learn-toast-progress{height:3px;background:#ffffff1a;border-radius:2px;overflow:hidden}.learn-toast-progress-bar{height:100%;width:30%;background:linear-gradient(90deg,var(--primary-color),var(--secondary-color));border-radius:2px;animation:progress-slide 2s ease-in-out infinite}@keyframes progress-slide{0%{width:10%;margin-left:0}50%{width:40%;margin-left:30%}to{width:10%;margin-left:90%}}.learn-toast-cancel{background:#ffffff1a;color:var(--text-secondary);border:1px solid rgba(255,255,255,.15)}@media (max-width: 480px){.learn-toast{top:auto;bottom:20px;right:10px;left:10px;max-width:none;width:auto;transform:translateY(calc(100% + 30px))}.learn-toast.active{transform:translateY(0)}.learn-toast-actions{flex-direction:column;gap:4px}}.audio-player-overlay{position:fixed;top:0;left:0;width:100%;height:100%;background:#000000e6;display:flex;align-items:center;justify-content:center;z-index:160;opacity:0;visibility:hidden;transition:all .3s ease;padding:20px}.audio-player-overlay.active{opacity:1;visibility:visible}.audio-player-box{background:linear-gradient(135deg,#1a1a4e,#0d0d2b);border:3px solid var(--primary-color);border-radius:20px;padding:35px;max-width:500px;width:90%;text-align:center;box-shadow:0 0 50px var(--primary-glow);transform:scale(.8);transition:transform .3s ease}.audio-player-overlay.active 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20px}.shop-title{font-size:2.5rem;text-align:center;color:var(--secondary-color);margin-bottom:10px}.shop-balance{text-align:center;font-size:1.3rem;color:var(--text-secondary);margin-bottom:40px}.shop-balance span{color:var(--secondary-color);font-weight:700}.shop-section{margin-bottom:40px}.shop-section-title{font-size:1.5rem;color:var(--primary-color);margin-bottom:20px;padding-bottom:10px;border-bottom:2px solid var(--primary-color)}.shop-items{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:20px}.shop-item{background:var(--answer-bg);border:2px solid var(--answer-border);border-radius:15px;padding:20px;transition:all .3s ease}.shop-item:hover{border-color:var(--primary-color);transform:translateY(-5px);box-shadow:0 10px 30px #00000080}.shop-item.owned{border-color:var(--success-color);opacity:.7}.shop-item-name{font-size:1.2rem;font-weight:700;margin-bottom:10px;color:var(--secondary-color)}.shop-item-desc{font-size:.9rem;color:var(--text-secondary);margin-bottom:15px}.shop-item-price{font-size:1.1rem;color:var(--primary-color);margin-bottom:15px}.shop-item-btn{width:100%;padding:10px;font-size:1rem;border:none;border-radius:8px;cursor:pointer;transition:all .3s ease}.shop-item-btn.buy{background:var(--primary-color);color:#fff}.shop-item-btn.buy:hover:not(:disabled){background:#06c}.shop-item-btn.activate{background:var(--success-color);color:#000}.shop-item-btn.active{background:var(--secondary-color);color:#000;cursor:default}.shop-item-btn:disabled{background:#333;color:#666;cursor:not-allowed}.auth-area{position:fixed;top:15px;right:15px;z-index:50}.auth-user{display:flex;align-items:center;gap:10px;background:#0009;border:1px solid rgba(255,255,255,.15);border-radius:30px;padding:6px 14px 6px 6px}.auth-avatar{width:32px;height:32px;border-radius:50%;border:2px solid var(--primary-color)}.auth-name{color:var(--text-color);font-size:.9rem;max-width:120px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.auth-logout-btn{background:#f443;border:1px solid rgba(255,68,68,.4);color:#f66;padding:4px 10px;border-radius:15px;font-size:.75rem;cursor:pointer;transition:all .3s ease}.auth-logout-btn:hover{background:#f446}.google-signin-btn{display:flex;align-items:center;gap:10px;background:#fff;color:#3c4043;border:1px solid #dadce0;border-radius:20px;padding:8px 20px 8px 12px;font-size:.9rem;font-weight:500;cursor:pointer;transition:all .3s ease;white-space:nowrap;font-family:Roboto,Segoe UI,sans-serif}.google-signin-btn:hover{background:#f7f8f8;box-shadow:0 2px 8px #0003}.google-icon{flex-shrink:0}.auth-hint{color:var(--text-secondary);font-size:.75rem;margin-top:6px;text-align:center;max-width:200px;line-height:1.3}.class-card-tooltip{display:none;font-size:.7rem;color:var(--secondary-color);margin-top:6px;line-height:1.3}.auth-notice{color:var(--secondary-color);font-size:.85rem;text-align:center;padding:10px;background:#ffd7001a;border:1px solid rgba(255,215,0,.3);border-radius:8px;margin-bottom:10px}@media (max-width: 480px){.auth-area{top:10px;right:10px}.auth-name{display:none}.auth-user{padding:4px 10px 4px 4px}}.nav-back{position:fixed;top:20px;left:20px;z-index:50}.nav-back a{color:var(--text-secondary);text-decoration:none;font-size:1.2rem;display:flex;align-items:center;gap:10px;transition:color .3s ease}.nav-back a:hover{color:var(--primary-color)}@media (max-width: 768px){.title{font-size:2.5rem;letter-spacing:4px}.subtitle{font-size:1rem}.btn{padding:15px 40px;font-size:1.2rem}.answers-container{grid-template-columns:1fr}.game-header{flex-direction:column;gap:15px}.timer-bar{width:150px}.question-text{font-size:1.3rem}.lifelines-container{flex-wrap:wrap}}.fade-in{animation:fadeIn .5s ease forwards}@keyframes fadeIn{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.shake{animation:shake .5s ease-in-out}@keyframes shake{0%,to{transform:translate(0)}20%,60%{transform:translate(-10px)}40%,80%{transform:translate(10px)}}.theme-cosmic .stars{position:fixed;top:0;left:0;width:100%;height:100%;pointer-events:none;z-index:0;background-image:radial-gradient(2px 2px at 20px 30px,white,transparent),radial-gradient(2px 2px at 40px 70px,white,transparent),radial-gradient(1px 1px at 90px 40px,white,transparent),radial-gradient(2px 2px at 160px 120px,white,transparent),radial-gradient(1px 1px at 230px 80px,white,transparent),radial-gradient(2px 2px at 300px 150px,white,transparent),radial-gradient(1px 1px at 400px 60px,white,transparent),radial-gradient(2px 2px at 500px 200px,white,transparent),radial-gradient(1px 1px at 600px 100px,white,transparent),radial-gradient(2px 2px at 700px 250px,white,transparent);background-size:800px 300px;animation:twinkle 5s ease-in-out infinite}@keyframes twinkle{0%,to{opacity:.5}50%{opacity:1}}.formulas-modal{position:fixed;top:0;left:0;width:100%;height:100%;background:#000000f2;display:flex;align-items:center;justify-content:center;z-index:300;opacity:0;visibility:hidden;transition:all .3s ease;overflow-y:auto;padding:20px}.formulas-modal.active{opacity:1;visibility:visible}.formulas-content{background:var(--answer-bg);border:3px solid var(--primary-color);border-radius:20px;padding:30px;max-width:700px;width:100%;max-height:90vh;overflow-y:auto;position:relative;box-shadow:0 0 50px var(--primary-glow)}.formulas-close{position:absolute;top:15px;right:20px;font-size:2rem;color:var(--text-secondary);background:none;border:none;cursor:pointer;transition:color .3s ease}.formulas-close:hover{color:var(--error-color)}.formulas-title{font-size:2rem;color:var(--secondary-color);text-align:center;margin-bottom:30px;text-shadow:0 0 10px var(--secondary-color)}.formulas-section{margin-bottom:25px}.formulas-section h3{font-size:1.3rem;color:var(--primary-color);margin-bottom:15px;padding-bottom:8px;border-bottom:2px solid var(--primary-color)}.formula-item{display:flex;align-items:flex-start;gap:15px;padding:10px 0;border-bottom:1px solid rgba(255,255,255,.1)}.formula-item:last-child{border-bottom:none}.formula-letter{font-family:Courier New,monospace;font-size:1.2rem;font-weight:700;color:var(--secondary-color);min-width:80px;background:#ffd7001a;padding:5px 10px;border-radius:5px;text-align:center}.formula-desc{color:var(--text-color);font-size:1rem;line-height:1.5}.formula-box{background:#1e90ff1a;border:2px solid var(--primary-color);border-radius:12px;padding:15px;margin-bottom:15px}.formula-name{font-size:1rem;color:var(--text-secondary);margin-bottom:8px}.formula-equation{font-family:Courier New,monospace;font-size:1.5rem;color:var(--secondary-color);text-align:center;padding:10px;background:#0000004d;border-radius:8px;margin-bottom:8px}.formula-explain{font-size:.9rem;color:var(--text-secondary);text-align:center;font-style:italic}@media (max-width: 768px){.formulas-content{padding:20px}.formulas-title{font-size:1.5rem}.formula-item{flex-direction:column;gap:8px}.formula-letter{min-width:auto}.formula-equation{font-size:1.2rem}}.daily-section{background:linear-gradient(135deg,#ffd7001a,#ff8c001a);border:2px solid var(--secondary-color);border-radius:15px;padding:20px;margin:30px 0;text-align:center}.daily-title{font-size:1.3rem;color:var(--secondary-color);margin-bottom:10px;text-transform:uppercase;letter-spacing:2px}.daily-status{color:var(--text-secondary);margin-bottom:15px}.daily-status .bonus{color:var(--success-color);font-weight:700}.btn-daily{background:linear-gradient(135deg,#ff8c00,#f60);color:#fff;padding:12px 30px;font-size:1.1rem;border:none;border-radius:8px;cursor:pointer;transition:all .3s ease;text-decoration:none;display:inline-block}.btn-daily:hover:not(.disabled){transform:scale(1.05);box-shadow:0 0 20px #ff8c0080}.btn-daily.disabled{background:#555;cursor:not-allowed;opacity:.7}.daily-countdown{margin-top:10px;font-size:1.5rem;font-family:Courier New,monospace;color:var(--secondary-color)}.leaderboard-section{background:#0000004d;border:1px solid var(--primary-color);border-radius:15px;padding:20px;margin:20px 0;text-align:center}.leaderboard-title{font-size:1.2rem;color:var(--primary-color);margin-bottom:15px}.leaderboard-preview{display:flex;flex-direction:column;gap:8px}.leaderboard-preview-entry{display:flex;justify-content:space-between;align-items:center;padding:8px 15px;background:#ffffff0d;border-radius:8px}.leaderboard-medal{font-size:1.5rem}.leaderboard-preview-score{color:var(--secondary-color);font-weight:700}.leaderboard-empty{color:var(--text-secondary);font-style:italic}.leaderboard-list{display:flex;flex-direction:column;gap:10px}.leaderboard-entry{display:grid;grid-template-columns:50px 1fr 1fr 100px;align-items:center;padding:12px 15px;background:#ffffff0d;border-radius:8px;gap:10px}.leaderboard-entry.top-3{background:#ffd7001a;border:1px solid var(--secondary-color)}.leaderboard-rank{font-size:1.3rem;font-weight:700;color:var(--secondary-color)}.leaderboard-name{color:var(--text-color)}.leaderboard-score{color:var(--success-color);font-weight:700}.leaderboard-date{color:var(--text-secondary);font-size:.9rem}.leaderboard-position{color:var(--secondary-color);font-size:1.1rem;margin-top:10px}.sound-toggles{display:flex;justify-content:center;gap:15px;margin-top:20px}.sound-toggle{background:#ffffff1a;border:1px solid var(--text-secondary);color:var(--text-secondary);padding:8px 15px;border-radius:20px;cursor:pointer;transition:all .3s ease;font-size:.9rem}.sound-toggle:hover{background:#fff3}.sound-toggle.active{background:var(--primary-color);border-color:var(--primary-color);color:#fff}.btn-achievements{background:linear-gradient(135deg,#e74c3c,#c0392b);color:#fff;clip-path:polygon(10% 0%,90% 0%,100% 50%,90% 100%,10% 100%,0% 50%);box-shadow:0 0 20px #e74c3c80}.btn-achievements:hover{transform:scale(1.05);box-shadow:0 0 40px #e74c3cb3}.difficulty-indicator{display:flex;flex-direction:column;align-items:center;gap:2px;font-size:.9rem}.difficulty-indicator .multiplier{color:var(--secondary-color);font-size:.8rem}.streak-counter{display:none;align-items:center;gap:8px;background:linear-gradient(135deg,#ff640033,#ff320033);border:2px solid #ff6600;border-radius:10px;padding:8px 15px;animation:streak-pulse 1s ease-in-out infinite}.streak-counter.active{display:flex}@keyframes streak-pulse{0%,to{box-shadow:0 0 10px #ff640080}50%{box-shadow:0 0 25px #ff6400cc}}.streak-fire{font-size:1.2rem}.streak-count{font-size:1.3rem;font-weight:700;color:#f60}.streak-multiplier{font-size:.9rem;color:var(--secondary-color)}.streak-bonus{font-size:.9rem;color:#f60;margin-left:10px}.keyboard-hints{display:flex;justify-content:center;gap:20px;margin-top:15px;flex-wrap:wrap}.keyboard-hints .hint{font-size:.8rem;color:var(--text-secondary);background:#ffffff0d;padding:5px 10px;border-radius:5px}.floating-money{position:fixed;top:50%;left:50%;transform:translate(-50%,-50%);font-size:2.5rem;font-weight:700;z-index:1000;pointer-events:none;animation:float-up 2s ease-out forwards}.floating-money.positive{color:var(--success-color);text-shadow:0 0 20px rgba(0,255,136,.8)}.floating-money.negative{color:var(--error-color);text-shadow:0 0 20px rgba(255,68,68,.8)}@keyframes float-up{0%{opacity:1;transform:translate(-50%,-50%) scale(.5)}20%{opacity:1;transform:translate(-50%,-50%) scale(1.2)}to{opacity:0;transform:translate(-50%,-150%) scale(1)}}.achievement-notification{position:fixed;top:20px;right:-400px;width:350px;background:linear-gradient(135deg,#1e90fff2,#0064c8f2);border:2px solid var(--secondary-color);border-radius:15px;padding:20px;display:flex;align-items:center;gap:15px;z-index:2000;transition:right .5s ease;box-shadow:0 0 30px #1e90ff80}.achievement-notification.show{right:20px}.achievement-notification .achievement-icon{font-size:2.5rem}.achievement-notification .achievement-info{flex:1}.achievement-notification .achievement-title{font-size:.9rem;color:var(--secondary-color);text-transform:uppercase;letter-spacing:1px;margin-bottom:5px}.achievement-notification .achievement-name{font-size:1.2rem;font-weight:700;color:#fff;margin-bottom:3px}.achievement-notification .achievement-desc{font-size:.85rem;color:#fffc}.achievements-container{padding:40px 20px;max-width:900px;margin:0 auto}.achievements-title{font-size:2.5rem;text-align:center;color:var(--secondary-color);margin-bottom:10px;text-shadow:0 0 20px var(--secondary-color)}.achievements-subtitle{text-align:center;color:var(--text-secondary);margin-bottom:30px}.achievements-stats{text-align:center;margin-bottom:30px;font-size:1.2rem;color:var(--text-color)}.achievements-stats strong{color:var(--secondary-color)}.achievements-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:20px}.achievement-card{background:var(--answer-bg);border:2px solid var(--answer-border);border-radius:15px;padding:20px;display:flex;gap:15px;transition:all .3s ease}.achievement-card.unlocked{border-color:var(--success-color);background:linear-gradient(135deg,#00ff881a,#00c8640d)}.achievement-card.locked{opacity:.6}.achievement-card:hover{transform:translateY(-3px);box-shadow:0 10px 30px #0000004d}.achievement-card .achievement-icon{font-size:2.5rem;width:60px;height:60px;display:flex;align-items:center;justify-content:center;background:#ffffff1a;border-radius:10px}.achievement-card .achievement-info{flex:1}.achievement-card .achievement-name{font-size:1.1rem;font-weight:700;color:var(--text-color);margin-bottom:5px}.achievement-card .achievement-description{font-size:.9rem;color:var(--text-secondary);margin-bottom:10px}.achievement-progress{margin-top:10px}.achievement-progress .progress-bar{height:8px;background:#ffffff1a;border-radius:4px;overflow:hidden;margin-bottom:5px}.achievement-progress .progress-fill{height:100%;background:linear-gradient(90deg,var(--primary-color),var(--success-color));border-radius:4px;transition:width .3s ease}.achievement-progress .progress-text{font-size:.8rem;color:var(--text-secondary)}.formula-when{margin-top:10px;padding:10px;background:#27ae601a;border-left:3px solid #27ae60;border-radius:0 8px 8px 0;font-size:.9rem}.formula-example{margin-top:10px;padding:10px;background:#9b59b61a;border-left:3px solid #9b59b6;border-radius:0 8px 8px 0;font-size:.9rem}.formula-solution{display:block;margin-top:5px;font-family:Courier New,monospace}.formula-variants{margin-top:10px;padding:10px;background:#3498db1a;border-left:3px solid #3498db;border-radius:0 8px 8px 0;font-size:.9rem}.formula-mini{font-family:Courier New,monospace;color:var(--secondary-color);background:#0000004d;padding:2px 6px;border-radius:4px}.formula-tip{margin-top:10px;padding:10px;background:#e74c3c1a;border-left:3px solid #e74c3c;border-radius:0 8px 8px 0;font-size:.9rem;color:#e74c3c}.formula-tip-box{background:#0000004d;border-radius:10px;padding:15px}.tip-item{display:flex;align-items:center;gap:10px;padding:10px 0;border-bottom:1px solid rgba(255,255,255,.1)}.tip-item:last-child{border-bottom:none}.tip-keyword{flex:1;color:var(--text-secondary);font-size:.9rem}.tip-arrow{color:var(--primary-color);font-size:1.2rem}.tip-formula{font-family:Courier New,monospace;color:var(--secondary-color);font-weight:700}.setup-toggle{position:fixed;bottom:20px;right:20px;z-index:400;width:50px;height:50px;border-radius:50%;border:2px solid var(--primary-color);background:linear-gradient(135deg,#1e90ff26,#0009);color:var(--text-color);font-size:1.5rem;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .3s ease;box-shadow:0 0 15px var(--primary-glow)}.setup-toggle:hover{transform:scale(1.1);box-shadow:0 0 25px var(--primary-glow)}.setup-toggle.has-questions{border-color:var(--success-color);box-shadow:0 0 15px #0f86}.setup-panel{position:fixed;top:0;left:0;width:100%;height:100%;z-index:500;display:flex;align-items:center;justify-content:center;background:#000000b3;opacity:0;visibility:hidden;transition:opacity .25s ease}.setup-panel.active{opacity:1;visibility:visible}.setup-panel-inner{width:400px;max-width:calc(100vw - 40px);max-height:calc(100vh - 80px);background:linear-gradient(135deg,#0f0f32fc,#050514fc);border:1px solid rgba(30,144,255,.3);border-radius:16px;overflow:hidden;transform:scale(.95);transition:transform .25s ease;box-shadow:0 8px 40px #0009,0 0 20px var(--primary-glow)}.setup-panel.active .setup-panel-inner{transform:scale(1)}.setup-panel-header{display:flex;align-items:center;justify-content:space-between;padding:14px 18px;border-bottom:1px solid rgba(255,255,255,.08)}.setup-panel-header h3{font-size:.95rem;color:var(--primary-color);text-transform:uppercase;letter-spacing:2px;margin:0}.setup-panel-close{background:none;border:none;color:var(--text-secondary);font-size:1.5rem;cursor:pointer;padding:0;line-height:1;transition:color .3s ease}.setup-panel-close:hover{color:var(--error-color)}.setup-panel-body{padding:16px 18px;overflow-y:auto;max-height:calc(100vh - 160px)}.setup-field{margin-bottom:16px}.setup-field label{display:block;font-size:.85rem;color:var(--text-secondary);margin-bottom:6px;text-transform:uppercase;letter-spacing:1px}.setup-field input[type=text],.setup-field input[type=password],.setup-field textarea{width:100%;padding:10px 14px;border-radius:8px;border:1px solid rgba(255,255,255,.15);background:#0006;color:var(--text-color);font-size:.95rem;font-family:inherit;transition:border-color .3s ease}.setup-field input:focus,.setup-field textarea:focus{outline:none;border-color:var(--primary-color);box-shadow:0 0 10px #1e90ff33}.setup-field textarea{resize:vertical;min-height:60px}.upload-area{border:2px dashed rgba(255,255,255,.2);border-radius:12px;padding:20px;text-align:center;cursor:pointer;transition:all .3s ease;position:relative}.upload-area:hover,.upload-area.dragover{border-color:var(--primary-color);background:#1e90ff0d}.upload-area.has-image{border-color:var(--success-color);border-style:solid}.upload-area .upload-icon{font-size:2rem;margin-bottom:8px;opacity:.6}.upload-area .upload-text{font-size:.85rem;color:var(--text-secondary)}.upload-area .upload-hint{font-size:.75rem;color:#ffffff4d;margin-top:4px}.upload-preview{max-width:100%;max-height:150px;border-radius:8px;margin-top:10px}.upload-remove{position:absolute;top:8px;right:8px;background:#f44c;border:none;color:#fff;width:24px;height:24px;border-radius:50%;cursor:pointer;font-size:.9rem;display:flex;align-items:center;justify-content:center;transition:background .3s ease}.upload-remove:hover{background:#f44}.btn-generate{width:100%;padding:14px 20px;font-size:1.1rem;font-weight:700;text-transform:uppercase;letter-spacing:2px;border:none;border-radius:10px;cursor:pointer;background:linear-gradient(135deg,#00c853,#009624);color:#fff;transition:all .3s ease;box-shadow:0 0 20px #00c8534d;margin-top:8px}.btn-generate:hover:not(:disabled){transform:scale(1.02);box-shadow:0 0 30px #00c85380}.btn-generate:disabled{background:linear-gradient(135deg,#555,#333);cursor:not-allowed;box-shadow:none;opacity:.7}.generate-status{text-align:center;font-size:.85rem;margin-top:12px;min-height:20px}.generate-status.success{color:var(--success-color)}.generate-status.error{color:var(--error-color)}.loading-overlay{position:fixed;top:0;left:0;width:100%;height:100%;background:#000000d9;display:flex;flex-direction:column;align-items:center;justify-content:center;z-index:500;opacity:0;visibility:hidden;transition:all .3s ease}.loading-overlay.active{opacity:1;visibility:visible}.loading-spinner{width:60px;height:60px;border:4px solid rgba(255,255,255,.1);border-top-color:var(--primary-color);border-radius:50%;animation:spin 1s linear infinite;margin-bottom:20px}@keyframes spin{to{transform:rotate(360deg)}}.loading-text{font-size:1.2rem;color:var(--text-color);letter-spacing:2px}.loading-subtext{font-size:.85rem;color:var(--text-secondary);margin-top:8px}.class-selector{display:flex;flex-wrap:wrap;justify-content:center;gap:12px;margin-bottom:30px;max-width:700px;width:100%}.class-card{position:relative;background:var(--answer-bg);border:2px solid var(--answer-border);border-radius:12px;padding:14px 20px;min-width:160px;max-width:220px;cursor:pointer;transition:all .3s ease;text-align:center}.class-card:hover{border-color:var(--primary-color);transform:translateY(-3px);box-shadow:0 8px 25px #0006}.class-card.active{border-color:var(--success-color);box-shadow:0 0 20px #00ff884d}.class-card-name{font-size:1rem;font-weight:700;color:var(--text-color);margin-bottom:4px;word-break:break-word}.class-card-info{font-size:.8rem;color:var(--text-secondary)}.class-card-badge{display:inline-block;font-size:.65rem;color:var(--secondary-color);background:#ffd70026;border:1px solid rgba(255,215,0,.3);border-radius:4px;padding:2px 6px;margin-top:6px;text-transform:uppercase;letter-spacing:1px}.class-card-delete{position:absolute;top:6px;right:6px;width:22px;height:22px;border-radius:50%;border:none;background:#ff4444b3;color:#fff;font-size:.75rem;cursor:pointer;display:none;align-items:center;justify-content:center;line-height:1;transition:background .3s ease}.class-card:hover .class-card-delete{display:flex}.class-card-delete:hover{background:#f44}.class-card-add{border-style:dashed;border-color:#fff3;display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:80px;opacity:.7;transition:all .3s ease}.class-card-add:hover{opacity:1;border-color:var(--primary-color);background:#1e90ff0d}.class-card-add-icon{font-size:1.8rem;color:var(--primary-color);margin-bottom:4px}.class-card-add-text{font-size:.8rem;color:var(--text-secondary)}@keyframes bounce-in{0%{transform:scale(0);opacity:0}50%{transform:scale(1.1)}to{transform:scale(1);opacity:1}}.bounce-in{animation:bounce-in .5s ease forwards}@media (max-width: 480px){.title{font-size:2rem;letter-spacing:3px}.subtitle{font-size:.9rem;margin-bottom:40px}.btn{padding:12px 30px;font-size:1rem}.game-header{flex-wrap:wrap;gap:10px}.timer-bar{width:120px}.question-container{padding:20px}.question-text{font-size:1.1rem}.answer-btn{padding:12px 15px;font-size:1rem}.lifelines-container{gap:10px}.lifeline-btn{padding:10px 15px;font-size:.9rem}.keyboard-hints{display:none}.explanation-box{padding:20px 15px;width:95%}.explanation-result{font-size:1.5rem}.explanation-money{font-size:1.2rem}.correct-answer-text{font-size:1.1rem}.explanation-content{padding:12px;margin-bottom:15px}.daily-section{padding:15px}.achievements-grid{grid-template-columns:1fr}.achievement-card{padding:15px}.achievement-card .achievement-icon{font-size:2rem;width:50px;height:50px}.achievement-notification{width:90%;right:-100%}.achievement-notification.show{right:5%}.leaderboard-entry{grid-template-columns:40px 1fr 1fr}.leaderboard-entry .leaderboard-date{display:none}.floating-money{font-size:1.8rem}.streak-counter{padding:5px 10px}.streak-fire{font-size:1rem}.streak-count{font-size:1.1rem}.class-selector{flex-direction:column;align-items:center}.class-card{min-width:200px;max-width:280px;width:100%}.setup-panel-inner{width:calc(100vw - 20px)}.setup-toggle{bottom:12px;right:12px;width:44px;height:44px;font-size:1.3rem}.btn-generate{font-size:.95rem;padding:12px 16px}}.login-prompt-overlay{position:fixed;top:0;left:0;width:100%;height:100%;z-index:600;display:flex;align-items:center;justify-content:center;background:#000000b3;animation:fadeIn .2s ease}.login-prompt-box{width:380px;max-width:calc(100vw - 40px);background:linear-gradient(135deg,#0f0f32fc,#050514fc);border:1px solid rgba(30,144,255,.3);border-radius:16px;padding:32px 28px;text-align:center;position:relative;box-shadow:0 8px 40px #0009,0 0 20px var(--primary-glow)}.login-prompt-close{position:absolute;top:12px;right:16px;background:none;border:none;color:var(--text-secondary);font-size:1.5rem;cursor:pointer;line-height:1;transition:color .3s ease}.login-prompt-close:hover{color:var(--error-color)}.login-prompt-title{font-size:1.2rem;color:var(--primary-color);margin:0 0 12px;text-transform:uppercase;letter-spacing:2px}.login-prompt-text{font-size:.95rem;color:var(--text-secondary);margin:0 0 24px;line-height:1.5}.login-prompt-box .google-signin-btn{margin:0 auto}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}