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

body, html {
    width: 100%;
    height: 100%;
    height: 100dvh;
    overflow: hidden;
    background-color: #000;
    touch-action: none;
    user-select: none;
    -webkit-user-select: none;
    -webkit-tap-highlight-color: transparent;
}

#xylophone {
    display: flex;
    width: 100%;
    height: 100%;
    height: 100dvh;
    padding-bottom: env(safe-area-inset-bottom);
}

#home-btn {
    position: absolute;
    top: 20px;
    left: 20px;
    font-size: 40px;
    opacity: 0.2;
    z-index: 100;
    cursor: pointer;
    user-select: none;
    -webkit-user-select: none;
}

.key {
    flex: 1;
    height: 100%;
    background-color: var(--bg);
    border: 1px solid rgba(0, 0, 0, 0.1);
    transition: filter 0.1s, transform 0.1s;
    cursor: pointer;
}

.key.active {
    filter: brightness(1.3) saturate(1.2);
    transform: scaleX(0.98);
    z-index: 1;
    box-shadow: inset 0 0 20px rgba(255, 255, 255, 0.5);
}