html, body { height: 100%; }
body { margin: 0; overflow: hidden; background: #0b0b0f; }
#visualizer { display: block; width: 100vw; height: 100vh; }
.hidden-media { position: fixed; left: -9999px; width: 1px; height: 1px; }

.hint {
    position: fixed;
    left: 50%;
    top: 20px;
    transform: translateX(-50%);
    color: #aaa;
    font-family: Segoe UI, Tahoma, Geneva, Verdana, sans-serif;
    background: rgba(0, 0, 0, 0.4);
    padding: 6px 10px;
    border-radius: 6px;
    cursor: pointer;
    user-select: none;
    -webkit-user-select: none;
}
#filePicker { display: none; }