body, html {
    height: 100%;
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
}
#controls {
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 300px;
    background: #f0f0f0;
    padding: 10px;
    box-shadow: 2px 0 5px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}
#controls.collapsed {
    transform: translateX(-100%);
}
#toggle-controls {
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    background: #007bff;
    color: white;
    border: none;
    padding: 5px 10px;
    cursor: pointer;
    z-index: 999;
}
#image-container {
    width: 100vw;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}
#image:not([src]),
#image[src=''] {
    display: none;
}