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

body, html {
    width: 100%;
    height: 100%;
    overflow: hidden;
    background-color: #ffffff;
    font-family: sans-serif;
}

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

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

#ui {
    position: absolute;
    top: 15px;
    left: 15px;
    font-size: 20px;
    font-weight: bold;
    color: #000000;
    pointer-events: none;
    text-shadow: 1px 1px 2px rgba(255,255,255,0.8);
}

#mobile-hint {
    position: absolute;
    bottom: 20px;
    width: 100%;
    text-align: center;
    font-size: 14px;
    color: #666666;
    pointer-events: none;
    animation: fadeOut 4s forwards;
    animation-delay: 2s;
}

@keyframes fadeOut {
    to { opacity: 0; }
}