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

body {
    width: 100vw;
    height: 100vh;
    background: radial-gradient(circle at bottom, #1b2735 0%, #090a0f 100%);
    overflow: hidden;
    font-family: 'Arial', sans-serif;
}

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

.controls {
    position: absolute;
    top: 20px;
    right: 20px;
    z-index: 10;
}

.icon-btn {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: #fff;
    padding: 8px 15px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    backdrop-filter: blur(5px);
    transition: all 0.3s ease;
}

.icon-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(1.05);
}

.instruction {
    position: absolute;
    bottom: 20px;
    width: 100%;
    text-align: center;
    color: rgba(255, 255, 255, 0.5);
    font-size: 14px;
    pointer-events: none;
    user-select: none;
}