body {
    margin: 0;
    font-family: system-ui, sans-serif;
    background: #111;
    color: #eee;
}

body.light {
    background: #f5f5f5;
    color: #222;
}

button {
    background: #333;
    color: #eee;
    border: 1px solid #555;
    border-radius: 4px;
    padding: 6px 10px;
    cursor: pointer;
}

button:hover:not(:disabled) {
    background: #444;
}

button:disabled {
    opacity: 0.4;
}

#load-section,
#nav-section {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 14px;
    background: #1a1a1a;
    border-bottom: 1px solid #333;
}

#nav-section {
    background: #222;
}

#main-layout {
    display: flex;
    height: calc(100vh - 160px);
}

#left-side {
    flex: 2;
    display: flex;
    flex-direction: column;
    gap: 12px;
    padding: 10px;
}

#viewer {
    height: 70vh;
    overflow-y: auto;
    background: #000;
    border: 1px solid #333;
    border-radius: 6px;
    padding: 10px;
}

#imageWrapper {
    position: relative;
    width: 100%;
    display: flex;
    justify-content: center;
}

#pageImage {
    max-width: 100%;
    height: auto;
    transform-origin: center center;
}

#selectionBox {
    position: absolute;
    border: 2px dashed #00ff00;
    background: rgba(0, 255, 0, 0.1);
    display: none;
    pointer-events: none;
}

#thumbnails {
    display: flex;
    gap: 10px;
    padding: 10px;
    overflow-x: auto;
    background: #1a1a1a;
    border: 1px solid #333;
    border-radius: 6px;
}

.thumb-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.thumbnail {
    width: 90px;
    height: 130px;
    border: 2px solid #555;
    cursor: pointer;
    object-fit: cover;
}

.thumbnail.active {
    border-color: #00ff00;
}

#save-section {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

#controls {
    flex: 1;
    padding: 12px;
    background: #181818;
    border-left: 1px solid #333;
    overflow-y: auto;
}

.slider-row {
    display: grid;
    grid-template-columns: 90px 1fr;
    gap: 10px;
    margin-bottom: 10px;
}

#historyPanel {
    max-height: 200px;
    overflow-y: auto;
    border: 1px solid #333;
    padding: 6px;
    border-radius: 4px;
    background: #121212;
}