:root {
    --primary-color: #00f3ff;
    --secondary-color: #ff0055;
    --bg-color: #0a0a12;
    --ui-font: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    user-select: none;
}

body {
    background-color: var(--bg-color);
    color: white;
    font-family: var(--ui-font);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
    display: flex;
    justify-content: center;
    align-items: center;
}

#game-container {
    position: relative;
    width: 100%;
    height: 100%;
    max-width: 1280px;
    max-height: 720px;
    box-shadow: 0 0 50px rgba(0, 243, 255, 0.1);
    background: #111;
    border: 1px solid #333;
}

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

#ui-layer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

#score-board {
    position: absolute;
    top: 20px;
    left: 20px;
    font-size: 24px;
    font-weight: bold;
    color: var(--primary-color);
    text-shadow: 0 0 10px var(--primary-color);
}

#health-bar-container {
    position: absolute;
    top: 20px;
    right: 20px;
    width: 200px;
    height: 20px;
    background: rgba(0, 0, 0, 0.5);
    border: 2px solid #fff;
    border-radius: 4px;
    overflow: hidden;
}

#health-bar {
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, #00ff00, #aaff00);
    transition: width 0.2s ease-out;
}

#start-screen, #game-over-screen, #victory-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    pointer-events: auto;
    backdrop-filter: blur(5px);
}

.hidden {
    display: none !important;
}

h1 {
    font-size: 64px;
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 4px;
    background: linear-gradient(to bottom, #fff, #aaa);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 10px 20px rgba(0,0,0,0.5);
}

#game-over-screen h1 {
    background: linear-gradient(to bottom, #ff5555, #aa0000);
    -webkit-background-clip: text;
}

#victory-screen h1 {
    background: linear-gradient(to bottom, #55ff55, #00aa00);
    -webkit-background-clip: text;
}

p {
    font-size: 18px;
    color: #ccc;
    margin-bottom: 40px;
}

button {
    padding: 15px 40px;
    font-size: 24px;
    font-weight: bold;
    color: var(--bg-color);
    background: var(--primary-color);
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s;
    text-transform: uppercase;
    box-shadow: 0 0 20px rgba(0, 243, 255, 0.4);
}

button:hover {
    transform: scale(1.05);
    box-shadow: 0 0 40px rgba(0, 243, 255, 0.6);
    background: #fff;
}

button:active {
    transform: scale(0.95);
}