body {
    margin: 0;
    padding: 20px;
    font-family: Arial, sans-serif;
    background: linear-gradient(135deg, #024237, #076311);
    color: white;
    text-align: center;
}

.game-container {
    max-width: 800px;
    margin: 0 auto;
}

h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.5);
}

.score {
    font-size: 1.5em;
    margin-bottom: 10px;
    font-weight: bold;
}

.lives {
    font-size: 1.3em;
    margin-bottom: 20px;
    font-weight: bold;
    color: #ff6b6b;
}

.game-area {
    width: 600px;
    height: 400px;
    background: rgba(0, 0, 50, 0.3);
    border: 3px solid #fff;
    border-radius: 10px;
    margin: 0 auto;
    position: relative;
    overflow: hidden;
}

.player {
    position: absolute;
    bottom: 10px;
    left: 275px;
    font-size: 2em;
    transition: left 0.1s ease;
}

.obstacle {
    position: absolute;
    font-size: 2em;
    animation: fall 2.5s linear;
}

.obstacle.hit {
    animation: explode 0.5s ease-out;
}

.alien {
    position: absolute;
    font-size: 1.8em;
    animation: fall 3s linear;
}

.alien.shot {
    animation: explode 0.3s ease-out;
}

.bullet {
    position: absolute;
    font-size: 1em;
    color: #ffff00;
    animation: shoot 1s linear;
}

@keyframes explode {
    0% { 
        transform: scale(1); 
        opacity: 1; 
        filter: brightness(1);
    }
    50% { 
        transform: scale(1.5); 
        opacity: 0.8; 
        filter: brightness(2);
    }
    100% { 
        transform: scale(2.5); 
        opacity: 0;
        filter: brightness(0);
    }
}

@keyframes shoot {
    from {
        bottom: 50px;
    }
    to {
        bottom: 400px;
    }
}

@keyframes fall {
    from {
        top: -30px;
    }
    to {
        top: 400px;
    }
}

.controls {
    margin-top: 20px;
}

.controls p {
    font-size: 1.2em;
    margin-bottom: 15px;
}

button {
    font-size: 1.2em;
    padding: 10px 20px;
    background: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s;
}

button:hover {
    background: #45a049;
}

button:disabled {
    background: #666;
    cursor: not-allowed;
}