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

body {
    overflow: hidden;
    background: #000;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

#game-container {
    width: 100vw;
    height: 100vh;
    position: relative;
}

#gameCanvas {
    display: block;
    width: 100%;
    height: 100%;
}

/* HUD Styles */
#hud {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    pointer-events: none;
    z-index: 100;
}

#health-bar {
    width: 250px;
    height: 30px;
    background: rgba(0, 0, 0, 0.7);
    border: 2px solid #00ffff;
    border-radius: 5px;
    position: relative;
    overflow: hidden;
    box-shadow: 0 0 15px rgba(0, 255, 255, 0.5);
}

#health-fill {
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, #ff0055, #ff3377);
    transition: width 0.3s ease;
    box-shadow: inset 0 0 20px rgba(255, 255, 255, 0.3);
}

#health-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #fff;
    font-weight: bold;
    text-shadow: 0 0 10px #000;
    font-size: 14px;
}

#score, #wave, #ammo {
    background: rgba(0, 0, 0, 0.7);
    padding: 10px 20px;
    border: 2px solid #00ffff;
    border-radius: 5px;
    color: #00ffff;
    font-size: 18px;
    font-weight: bold;
    text-shadow: 0 0 10px #00ffff;
    box-shadow: 0 0 15px rgba(0, 255, 255, 0.3);
}

#ammo {
    position: absolute;
    bottom: 20px;
    right: 20px;
}

/* Crosshair */
#crosshair {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
    z-index: 100;
}

.crosshair-line {
    position: absolute;
    background: rgba(255, 255, 255, 0.9);
    box-shadow: 0 0 5px #00ffff, 0 0 10px #00ffff;
}

.crosshair-line.horizontal {
    width: 20px;
    height: 2px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.crosshair-line.horizontal::before,
.crosshair-line.horizontal::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 2px;
    background: rgba(255, 255, 255, 0.9);
    box-shadow: 0 0 5px #00ffff, 0 0 10px #00ffff;
}

.crosshair-line.horizontal::before {
    left: -30px;
}

.crosshair-line.horizontal::after {
    right: -30px;
}

.crosshair-line.vertical {
    width: 2px;
    height: 20px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.crosshair-line.vertical::before,
.crosshair-line.vertical::after {
    content: '';
    position: absolute;
    width: 2px;
    height: 20px;
    background: rgba(255, 255, 255, 0.9);
    box-shadow: 0 0 5px #00ffff, 0 0 10px #00ffff;
}

.crosshair-line.vertical::before {
    top: -30px;
}

.crosshair-line.vertical::after {
    bottom: -30px;
}

.crosshair-dot {
    position: absolute;
    width: 4px;
    height: 4px;
    background: #ff0055;
    border-radius: 50%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    box-shadow: 0 0 5px #ff0055, 0 0 10px #ff0055;
}

/* Overlay Screens */
.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 200;
}

.overlay.hidden {
    display: none;
}

.overlay-content {
    text-align: center;
    color: #fff;
}

.overlay-content h1 {
    font-size: 72px;
    color: #00ffff;
    text-shadow: 0 0 20px #00ffff, 0 0 40px #00ffff, 0 0 60px #00ffff;
    margin-bottom: 20px;
    letter-spacing: 10px;
    animation: glow 2s ease-in-out infinite alternate;
}

@keyframes glow {
    from {
        text-shadow: 0 0 20px #00ffff, 0 0 40px #00ffff, 0 0 60px #00ffff;
    }
    to {
        text-shadow: 0 0 30px #00ffff, 0 0 60px #00ffff, 0 0 90px #00ffff, 0 0 120px #00ffff;
    }
}

.subtitle {
    font-size: 24px;
    color: #ff0055;
    text-shadow: 0 0 10px #ff0055;
    margin-bottom: 40px;
    letter-spacing: 5px;
}

.controls-info {
    background: rgba(0, 255, 255, 0.1);
    border: 1px solid #00ffff;
    border-radius: 10px;
    padding: 20px 40px;
    margin-bottom: 40px;
    display: inline-block;
}

.controls-info p {
    font-size: 16px;
    margin: 10px 0;
    color: #ccc;
}

.controls-info strong {
    color: #00ffff;
    min-width: 100px;
    display: inline-block;
}

.neon-btn {
    background: transparent;
    border: 2px solid #00ffff;
    color: #00ffff;
    padding: 15px 50px;
    font-size: 24px;
    cursor: pointer;
    border-radius: 5px;
    text-transform: uppercase;
    letter-spacing: 3px;
    transition: all 0.3s ease;
    box-shadow: 0 0 15px rgba(0, 255, 255, 0.5);
}

.neon-btn {
    pointer-events: auto;
}

.neon-btn:hover {
    background: #00ffff;
    color: #000;
    box-shadow: 0 0 30px rgba(0, 255, 255, 0.8), 0 0 60px rgba(0, 255, 255, 0.5);
}

#game-over-screen h1 {
    color: #ff0055;
    text-shadow: 0 0 20px #ff0055, 0 0 40px #ff0055, 0 0 60px #ff0055;
}

#game-over-screen p {
    font-size: 28px;
    margin: 15px 0;
    color: #fff;
}

#game-over-screen span {
    color: #00ffff;
    text-shadow: 0 0 10px #00ffff;
}

/* Damage Overlay */
#damage-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 150;
    background: radial-gradient(ellipse at center, transparent 0%, rgba(255, 0, 50, 0) 100%);
    opacity: 0;
    transition: opacity 0.1s ease;
}

#damage-overlay.active {
    opacity: 1;
    background: radial-gradient(ellipse at center, transparent 30%, rgba(255, 0, 50, 0.5) 100%);
}

/* Muzzle Flash Effect */
.muzzle-flash {
    position: absolute;
    bottom: 100px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 100px;
    background: radial-gradient(circle, rgba(255, 200, 50, 1) 0%, rgba(255, 100, 0, 0.5) 50%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
    opacity: 0;
    z-index: 100;
}

/* Kill notification */
.kill-notification {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -100px);
    color: #ff0055;
    font-size: 24px;
    font-weight: bold;
    text-shadow: 0 0 10px #ff0055;
    animation: killPop 0.5s ease-out forwards;
    pointer-events: none;
    z-index: 100;
}

@keyframes killPop {
    0% {
        opacity: 1;
        transform: translate(-50%, -100px) scale(0.5);
    }
    50% {
        transform: translate(-50%, -120px) scale(1.2);
    }
    100% {
        opacity: 0;
        transform: translate(-50%, -150px) scale(1);
    }
}

/* Reload indicator */
#reload-indicator {
    position: absolute;
    bottom: 80px;
    left: 50%;
    transform: translateX(-50%);
    color: #ffff00;
    font-size: 18px;
    font-weight: bold;
    text-shadow: 0 0 10px #ffff00;
    opacity: 0;
    transition: opacity 0.2s;
    pointer-events: none;
    z-index: 100;
}

#reload-indicator.visible {
    opacity: 1;
}