body { -webkit-tap-highlight-color: transparent; font-family: system-ui, -apple-system, sans-serif; }
        .answer.correct { border-color: #10b981 !important; background-color: #f0fdf4 !important; }
        .answer.correct div { background-color: #10b981 !important; color: white !important; border-color: #10b981 !important; }
        .answer.incorrect { border-color: #ef4444 !important; background-color: #fef2f2 !important; }
        .answer.incorrect div { background-color: #ef4444 !important; color: white !important; border-color: #ef4444 !important; }
        .glass-nav { background: rgba(255, 255, 255, 0.9); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); }
        .btn-disabled { opacity: 0.3; pointer-events: none;
        }
        .answer-content-collapsed {
            max-height: 120px;
            overflow: hidden;
            position: relative;
        }
        
        .answer-content-collapsed::after {
            content: "";
            position: absolute;
            bottom: 0;
            left: 0;
            right: 0;
            height: 60px;
            background: linear-gradient(to bottom, rgba(255,255,255,0), rgba(255,255,255,1));
        }
        
        .hero-bg { background: linear-gradient(135deg, #1e3a8a 0%, #3b82f6 100%); }
        .state-card:hover { transform: translateY(-5px); transition: 0.3s; }