:root {
    --bg-dark: #0a0a0a;
    --bg-panel: #161616;
    --bg-input: #252525;
    --border: #333;
    --accent: #007acc;
    --accent-hover: #0098ff;
    --text-main: #e0e0e0;
    --text-muted: #999;
}

body {
    margin: 0; padding: 0;
    background-color: var(--bg-dark); color: var(--text-main);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    display: flex; height: 100vh; overflow: hidden;
}

.sidebar {
    width: 320px; background-color: var(--bg-panel); border-right: 1px solid var(--border);
    display: flex; flex-direction: column; flex-shrink: 0;
}
.sidebar-content {
    padding: 20px; overflow-y: auto; flex: 1;
}
.sidebar-content::-webkit-scrollbar { width: 8px; }
.sidebar-content::-webkit-scrollbar-thumb { background: #444; border-radius: 4px; }

.tabs { display: flex; border-bottom: 1px solid var(--border); background: #111; }
.tab-btn {
    flex: 1; padding: 12px; background: transparent; color: var(--text-muted);
    border: none; border-bottom: 2px solid transparent; cursor: pointer;
    font-weight: bold; outline: none; transition: 0.2s; border-radius: 0;
}
.tab-btn.active { color: #fff; border-bottom-color: var(--accent); background: var(--bg-panel); }
.tab-btn:hover:not(.active) { color: #ccc; }

h2, h3 { margin: 0 0 15px 0; color: #fff; text-transform: uppercase; letter-spacing: 1px; }
h2 { font-size: 1.1rem; }
h3 { font-size: 0.85rem; margin-top: 15px; padding-bottom: 5px; border-bottom: 1px solid var(--border); color: var(--accent); }

.dropzone {
    border: 2px dashed var(--border); border-radius: 8px; padding: 20px;
    text-align: center; cursor: pointer; transition: all 0.2s; margin-bottom: 15px;
    background: rgba(255,255,255,0.02); font-size: 0.9rem; color: var(--text-muted);
}
.dropzone:hover, .dropzone.dragover { border-color: var(--accent); background: rgba(0, 122, 204, 0.1); color: #fff; }

.form-group { margin-bottom: 12px; }
.form-row { display: flex; gap: 10px; }
.form-row .form-group { flex: 1; }

label { display: block; margin-bottom: 4px; font-size: 0.8rem; color: var(--text-muted); }
input[type="number"], select, textarea {
    width: 100%; padding: 6px 8px; background-color: var(--bg-input); border: 1px solid var(--border);
    color: var(--text-main); border-radius: 4px; box-sizing: border-box; outline: none; font-size: 0.9rem;
}
input[type="number"]:focus, select:focus, textarea:focus { border-color: var(--accent); }
input[type="color"] { width: 100%; height: 32px; border: none; background: none; cursor: pointer; padding: 0; }

.checkbox-group { display: flex; align-items: center; gap: 8px; cursor: pointer; font-size: 0.9rem; margin-bottom: 10px; }
.checkbox-group input { cursor: pointer; }

button {
    background-color: var(--accent); color: #fff; border: none; padding: 8px 15px;
    border-radius: 4px; cursor: pointer; font-weight: bold; width: 100%; transition: 0.2s;
}
button:hover { background-color: var(--accent-hover); }
button.secondary { background-color: #444; margin-top: 5px; }
button.secondary:hover { background-color: #555; }

.disabled-section { opacity: 0.3; pointer-events: none; transition: 0.3s; }

.main { flex: 1; display: flex; flex-direction: column; overflow: hidden; background-color: var(--bg-dark); }

.toolbar {
    background-color: var(--bg-panel); border-bottom: 1px solid var(--border);
    padding: 10px 20px; display: flex; gap: 20px; align-items: center; flex-shrink: 0;
    flex-wrap: wrap; justify-content: space-between;
}

.preview-scroll-area {
    flex: 1; overflow: hidden; position: relative; display: flex; align-items: center; justify-content: center;
    background-image: linear-gradient(45deg, #111 25%, transparent 25%), linear-gradient(-45deg, #111 25%, transparent 25%), linear-gradient(45deg, transparent 75%, #111 75%), linear-gradient(-45deg, transparent 75%, #111 75%);
    background-size: 20px 20px; background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
}

.canvas-wrapper { position: relative; box-shadow: 0 5px 30px rgba(0,0,0,0.8); transform-origin: center; transition: transform 0.05s linear; }

.preview-layer { image-rendering: pixelated; position: absolute; top: 0; left: 0; opacity: 0; pointer-events: none; }

.mode-final #finalCanvas { opacity: 1; position: relative; pointer-events: auto; }
.mode-original #originalCanvas { opacity: 1; position: relative; pointer-events: auto; }
.mode-sbs { display: flex; gap: 15px; }
.mode-sbs .preview-layer { opacity: 1; position: relative; pointer-events: auto; }
.mode-slider #originalCanvas { opacity: 1; position: absolute; }
.mode-slider #finalCanvas { opacity: 1; position: relative; z-index: 2; pointer-events: auto; }

#sliderHandle {
    display: none; position: absolute; left: 50%; top: -5px; bottom: -5px;
    width: 2px; background: var(--accent); z-index: 5; cursor: ew-resize; transform: translateX(-50%);
    box-shadow: 0 0 10px rgba(0,0,0,0.8);
}
#sliderHandle::after {
    content: ''; position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
    width: 14px; height: 14px; background: var(--accent); border-radius: 50%; border: 2px solid #fff;
}
.mode-slider #sliderHandle { display: block; }

.css-grid-overlay {
    position: absolute; top: 0; left: 0; width: 100%; height: 100%;
    pointer-events: none; display: none; z-index: 10;
}

#panelResizer {
    height: 6px; background: var(--border); cursor: ns-resize; flex-shrink: 0;
    position: relative; z-index: 100; transition: background 0.2s;
}
#panelResizer::after {
    content: ''; position: absolute; left: 50%; top: 2px; width: 40px; height: 2px;
    background: #666; transform: translateX(-50%); border-radius: 1px;
}
#panelResizer:hover { background: var(--accent); }
#panelResizer:hover::after { background: #fff; }

.outputs-container { height: 250px; background-color: var(--bg-panel); padding: 10px 15px; overflow-y: auto; overflow-x: auto; flex-shrink: 0; }

.outputs-grid {
    display: grid; gap: 6px;
    justify-content: center; align-content: start;
    padding: 10px; background: #111; border-radius: 8px;
    width: max-content; margin: 0 auto;
}

.chunk-wrap {
    background-color: var(--bg-input); border: 1px solid var(--border); border-radius: 4px; padding: 6px;
    cursor: pointer; display: flex; flex-direction: column; align-items: center; transition: 0.2s;
    width: 90px; box-sizing: border-box; 
}
.chunk-wrap:hover { border-color: var(--accent); transform: translateY(-2px); box-shadow: 0 4px 10px rgba(0,0,0,0.5); background-color: #333; }
.chunk-wrap canvas { background: #000; border: 1px solid #000; width: 100%; height: auto; image-rendering: pixelated; border-radius: 3px; }
.chunk-label { margin-top: 6px; font-size: 0.75rem; font-weight: bold; color: #fff; text-align: center;}
.chunk-desc { font-size: 0.65rem; color: var(--text-muted); margin-top: 2px; text-align: center; line-height: 1.1;}