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

body {
    margin: 0;
    padding: 0;
    font-family: 'Arial', sans-serif;
    background: #000;
    color: #fff;
    overflow: hidden;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.game-container {
    position: relative;
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

#gameArea {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: none;
    opacity: 0;
    transition: opacity 0.5s ease-in-out;
}

#gameArea.fade-in {
    opacity: 1;
}

#gameArea canvas {
    width: 100%;
    height: 100%;
    display: block;
}

.screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: linear-gradient(135deg, #1a1a1a 0%, #000000 100%);
    z-index: 1000;
    opacity: 1;
    transition: opacity 0.5s ease-in-out;
    pointer-events: auto;
}

.screen.fade-out {
    opacity: 0;
    pointer-events: none;
}

.screen h1 {
    font-size: 4em;
    margin: 0;
    padding: 0;
    text-align: center;
    color: #ff0000;
    text-shadow: 0 0 10px rgba(255, 0, 0, 0.5),
                 0 0 20px rgba(255, 0, 0, 0.3),
                 0 0 30px rgba(255, 0, 0, 0.2);
    animation: glow 2s ease-in-out infinite alternate;
}

.screen p {
    font-size: 1.5em;
    margin: 20px 0;
    text-align: center;
    color: #fff;
}

.screen button {
    padding: 15px 30px;
    font-size: 1.2em;
    background: linear-gradient(45deg, #ff0000, #ff4444);
    border: none;
    border-radius: 5px;
    color: white;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    margin-top: 20px;
}

.screen button:hover {
    transform: scale(1.05);
    box-shadow: 0 0 20px rgba(255, 0, 0, 0.5);
}

.hud {
    position: absolute;
    top: 20px;
    left: 20px;
    display: flex;
    gap: 20px;
    z-index: 100;
    opacity: 0;
    transition: opacity 0.5s ease-in-out;
}

.hud.fade-in {
    opacity: 1;
}

.hud > div {
    background: rgba(0, 0, 0, 0.7);
    padding: 10px 15px;
    border-radius: 5px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.hud i {
    color: #ff0000;
}

.hidden {
    display: none !important;
}

.health {
    color: #ff4444;
}

.ammo {
    color: #44ff44;
}

.score {
    color: #4444ff;
}

.hud span {
    font-weight: bold;
    font-size: 20px;
    display: inline-block;
    min-width: 40px;
    transition: all 0.2s ease;
}

.hud span:not(:empty) {
    animation: pulse 0.3s ease;
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.2); }
    100% { transform: scale(1); }
}

@keyframes glow {
    from {
        text-shadow: 0 0 10px rgba(255, 0, 0, 0.5),
                     0 0 20px rgba(255, 0, 0, 0.3),
                     0 0 30px rgba(255, 0, 0, 0.2);
    }
    to {
        text-shadow: 0 0 20px rgba(255, 0, 0, 0.7),
                     0 0 30px rgba(255, 0, 0, 0.5),
                     0 0 40px rgba(255, 0, 0, 0.3);
    }
}

#gameOverScreen {
    z-index: 1001; /* Ensure it's above other elements */
}

#gameOverScreen button {
    cursor: pointer;
    pointer-events: auto;
}