@import url('https://fonts.googleapis.com/css2?family=Press+Start+2P&display=swap');
        
        body {
            font-family: 'Press Start 2P', cursive;
            image-rendering: pixelated;
            background: #0f172a;
            overflow-x: hidden;
        }
        
        .pixel-canvas {
            image-rendering: pixelated;
            box-shadow: 0 0 30px rgba(0,255,0,0.3);
            border: 4px solid #334155;
        }
        
        .retro-text { text-shadow: 3px 3px 0px #000; }
        .shake { animation: shake 0.5s; }
        .float-text { animation: float 1s ease-out forwards; }
        .pulse { animation: pulse 2s infinite; }
        
        @keyframes shake {
            0%, 100% { transform: translateX(0); }
            25% { transform: translateX(-5px); }
            75% { transform: translateX(5px); }
        }
        
        @keyframes float {
            0% { transform: translateY(0); opacity: 1; }
            100% { transform: translateY(-40px); opacity: 0; }
        }
        
        @keyframes pulse {
            0%, 100% { transform: scale(1); }
            50% { transform: scale(1.05); }
        }
        
        .boss-bar {
            background: linear-gradient(90deg, #ff0000 0%, #ff6600 50%, #ff0000 100%);
            background-size: 200% 100%;
            animation: shimmer 2s infinite;
        }
        
        @keyframes shimmer {
            0% { background-position: 200% 0; }
            100% { background-position: -200% 0; }
        }
        
        .difficulty-btn {
            transition: all 0.3s;
            position: relative;
        }
        
        .difficulty-btn::after {
            content: '';
            position: absolute;
            inset: -2px;
            border-radius: 0.5rem;
            opacity: 0;
            transition: opacity 0.3s;
        }
        
        .difficulty-btn:hover::after {
            opacity: 1;
            animation: borderPulse 1s infinite;
        }
        
        @keyframes borderPulse {
            0%, 100% { box-shadow: 0 0 10px currentColor; }
            50% { box-shadow: 0 0 20px currentColor; }
        }