.sp-panel {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-width: 0;
    overflow: hidden;
}

.sp-canvas-area {
    flex: 1;
    background: #111;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    min-width: 0;
}

.sp-canvas {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    display: block;
    image-rendering: pixelated;
}

.sp-canvas-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    font-size: 13px;
    background: #111;
}

.sp-progress-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 12px 16px;
    background: linear-gradient(transparent, rgba(0,0,0,0.8));
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.sp-progress-bar {
    height: 4px;
    background: rgba(255,255,255,0.15);
    border-radius: 2px;
    overflow: hidden;
}

.sp-progress-fill {
    height: 100%;
    background: var(--accent);
    border-radius: 2px;
    transition: width 0.1s linear;
}

.sp-progress-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
}

.sp-progress-text,
.sp-progress-timer {
    font-size: 11px;
    color: rgba(255,255,255,0.6);
    font-variant-numeric: tabular-nums;
    font-family: 'SF Mono', 'Menlo', monospace;
}

.sp-error-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 12px;
    background: rgba(0,0,0,0.8);
    color: var(--danger);
    padding: 24px;
    text-align: center;
    font-size: 13px;
}

.sp-retry-btn {
    padding: 6px 16px;
    background: var(--bg-surface);
    color: var(--text-primary);
    border-radius: var(--radius-sm);
    font-size: 12px;
    transition: background 0.15s;
}

.sp-retry-btn:hover {
    background: var(--bg-hover);
}

.sp-controls {
    flex-shrink: 0;
    height: var(--controls-height);
    background: var(--bg-panel);
    border-top: 1px solid var(--border);
    padding: 10px 12px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 8px;
}

.sp-controls-row {
    display: flex;
    align-items: flex-end;
    gap: 12px;
}

.sp-blend-group {
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.sp-spacer {
    flex: 1;
}

.sp-section-label {
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    color: var(--text-muted);
    font-weight: 600;
    flex-shrink: 0;
}

.sp-select {
    padding: 6px 8px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 12px;
    font-family: inherit;
    cursor: pointer;
    appearance: auto;
}

.sp-select:disabled {
    opacity: 0.5;
    cursor: default;
}

.sp-stack-btn {
    min-width: 96px;
    padding: 8px 16px;
    background: var(--accent);
    color: #fff;
    border-radius: var(--radius-md);
    font-size: 13px;
    font-weight: 600;
    transition: background 0.15s, opacity 0.15s;
}

.sp-stack-btn:hover:not(:disabled) {
    background: var(--accent-hover);
}

.sp-stack-btn:disabled {
    opacity: 0.5;
    cursor: default;
}

.sp-add-frame-btn {
    min-width: 96px;
    padding: 8px 16px;
    background: transparent;
    border: 1px solid var(--accent);
    color: var(--accent);
    border-radius: var(--radius-md);
    font-size: 13px;
    font-weight: 500;
    transition: background 0.15s, opacity 0.15s;
}

.sp-add-frame-btn:hover:not(:disabled) {
    background: rgba(74, 158, 255, 0.1);
}

.sp-add-frame-btn:disabled {
    opacity: 0.5;
    cursor: default;
}

.sp-undo-btn {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 8px 16px;
    background: var(--accent);
    color: #fff;
    border-radius: var(--radius-md);
    font-size: 13px;
    font-weight: 600;
    transition: background 0.15s;
    z-index: 2;
}

.sp-undo-btn:hover {
    background: var(--accent-hover);
}

.sp-export-btn {
    min-width: 96px;
    padding: 8px 16px;
    background: transparent;
    border: 1px solid var(--success);
    color: var(--success);
    border-radius: var(--radius-md);
    font-size: 13px;
    font-weight: 500;
    transition: background 0.15s, opacity 0.15s;
}

.sp-export-btn:hover:not(:disabled) {
    background: rgba(80, 250, 123, 0.1);
}

.sp-export-btn:disabled {
    opacity: 0.5;
    cursor: default;
}


@media (max-width: 56.25rem) {
    .sp-add-frame-btn { display: none; }
    .sp-stack-btn,
    .sp-export-btn { min-width: 0; }
}