* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 800px;
}

.header {
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 20px;
    border-radius: 10px 10px 0 0;
    text-align: center;
}

.header h1 {
    margin-bottom: 15px;
    font-size: 32px;
}

.stats {
    display: flex;
    justify-content: space-around;
    gap: 20px;
    font-size: 18px;
}

.stats span {
    background: rgba(255, 255, 255, 0.1);
    padding: 8px 16px;
    border-radius: 5px;
}

.game-area {
    position: relative;
    width: 100%;
    height: 600px;
    background: linear-gradient(45deg, #1a1a2e 25%, transparent 25%, transparent 75%, #1a1a2e 75%, #1a1a2e),
                linear-gradient(45deg, #1a1a2e 25%, transparent 25%, transparent 75%, #1a1a2e 75%, #1a1a2e);
    background-size: 40px 40px;
    background-position: 0 0, 20px 20px;
    background-color: #2d2d44;
    border: 3px solid #667eea;
    overflow: hidden;
}

.player-tank {
    position: absolute;
    width: 30px;
    height: 30px;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 30 30"><rect width="30" height="30" fill="%2300ff00"/><rect x="10" y="2" width="10" height="15" fill="%2300ff00"/></svg>');
    background-size: cover;
    transition: none;
}

.bullet {
    position: absolute;
    width: 4px;
    height: 10px;
    background: #ffff00;
    border-radius: 2px;
}

.enemy-tank {
    position: absolute;
    width: 30px;
    height: 30px;
    background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 30 30"><rect width="30" height="30" fill="%23ff0000"/><rect x="10" y="2" width="10" height="15" fill="%23ff0000"/></svg>');
    background-size: cover;
}

.explosion {
    position: absolute;
    width: 30px;
    height: 30px;
    background: radial-gradient(circle, #ffff00, #ff6600, transparent);
    border-radius: 50%;
    animation: explode 0.5s ease-out;
}

@keyframes explode {
    0% {
        width: 30px;
        height: 30px;
        opacity: 1;
    }
    100% {
        width: 60px;
        height: 60px;
        opacity: 0;
    }
}

.controls {
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 15px;
    text-align: center;
    border-radius: 0 0 10px 10px;
    font-size: 14px;
}

.game-over-screen {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.9);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.game-over-screen.hidden {
    display: none;
}

.game-over-content {
    background: #1a1a2e;
    border: 3px solid #667eea;
    border-radius: 10px;
    padding: 40px;
    text-align: center;
    color: white;
}

.game-over-content h2 {
    font-size: 36px;
    margin-bottom: 20px;
    color: #ff6600;
}

.game-over-content p {
    font-size: 24px;
    margin-bottom: 30px;
}

.game-over-content button {
    background: #667eea;
    color: white;
    border: none;
    padding: 12px 30px;
    font-size: 18px;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s;
}

.game-over-content button:hover {
    background: #764ba2;
}