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

body {
    font-family: 'Arial', sans-serif;
    background: linear-gradient(135deg, #0c0c0c 0%, #1a1a2e 50%, #16213e 100%);
    color: white;
    overflow: hidden;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.game-container {
    position: relative;
    width: 800px;
    height: 600px;
    border: 2px solid #4a90e2;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 0 20px rgba(74, 144, 226, 0.3);
}

#gameCanvas {
    display: block;
    background: linear-gradient(to bottom, #000428 0%, #004e92 100%);
    width: 100%;
    height: 100%;
}

.ui-overlay {
    position: absolute;
    top: 20px;
    left: 20px;
    z-index: 10;
    display: flex;
    gap: 30px;
    font-size: 18px;
    font-weight: bold;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.8);
}

.score, .lives, .level {
    background: rgba(0, 0, 0, 0.7);
    padding: 10px 15px;
    border-radius: 5px;
    border: 1px solid #4a90e2;
}

.level-control {
    display: flex;
    gap: 5px;
}

.level-control button {
    background: rgba(0, 0, 0, 0.7);
    color: #4a90e2;
    border: 1px solid #4a90e2;
    padding: 5px 10px;
    border-radius: 3px;
    cursor: pointer;
    font-size: 14px;
    font-weight: bold;
}

.level-control button:hover {
    background: rgba(74, 144, 226, 0.2);
}

.start-screen, .game-over {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 20;
}

.start-screen h1 {
    font-size: 48px;
    margin-bottom: 20px;
    color: #4a90e2;
    text-shadow: 0 0 10px rgba(74, 144, 226, 0.5);
}

.start-screen p {
    font-size: 18px;
    margin-bottom: 30px;
    color: #ccc;
}

.game-over h2 {
    font-size: 36px;
    margin-bottom: 20px;
    color: #e74c3c;
}

.game-over p {
    font-size: 20px;
    margin-bottom: 30px;
    color: #ccc;
}

button {
    background: linear-gradient(45deg, #4a90e2, #357abd);
    color: white;
    border: none;
    padding: 15px 30px;
    font-size: 18px;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
}

button:hover {
    background: linear-gradient(45deg, #357abd, #4a90e2);
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
}

button:active {
    transform: translateY(0);
}

@media (max-width: 850px) {
    .game-container {
        width: 95vw;
        height: 70vh;
    }
    
    .start-screen h1 {
        font-size: 32px;
    }
    
    .ui-overlay {
        font-size: 14px;
        gap: 15px;
    }
}