body {
    margin: 0;
    overflow: hidden;
    background: #0d1a0d;
    font-family: 'Courier New', Courier, monospace;
    user-select: none;
}
#game-canvas {
    display: block;
    width: 100vw;
    height: 100vh;
}
#ui {
    position: absolute;
    top: 20px;
    left: 20px;
    color: #fff;
    pointer-events: none;
    text-shadow: 2px 2px 4px #000;
    z-index: 10;
}
#instructions {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    color: #fff;
    text-align: center;
    pointer-events: none;
    text-shadow: 2px 2px 4px #000;
    font-size: 16px;
    white-space: nowrap;
    z-index: 10;
}
nav {
    position: absolute;
    top: 10px;
    right: 10px;
    z-index: 10;
}
nav a {
    color: white;
    text-decoration: none;
    background: rgba(0,0,0,0.5);
    padding: 5px 10px;
    border-radius: 5px;
}
#aim-guide {
    position: absolute;
    pointer-events: none;
    z-index: 5;
}