Add a few styles needed for timeline

src/webviews/apps/plus/graph/GraphWrapper.tsx

@@ -48,6 +48,8 @@ const getStyleProps = (
 		cssVariables: {
 			'--app__bg0': computedStyle.getPropertyValue('--color-background'),
 			'--panel__bg0': computedStyle.getPropertyValue('--graph-panel-bg'),
+			'--panel__bg1': computedStyle.getPropertyValue('--graph-panel-bg2'),
+			'--section-border': computedStyle.getPropertyValue('--graph-panel-bg2'),
 			'--text-selected': computedStyle.getPropertyValue('--color-foreground'),
 			'--text-normal': computedStyle.getPropertyValue('--color-foreground--85'),
 			'--text-secondary': computedStyle.getPropertyValue('--color-foreground--65'),

src/webviews/apps/shared/theme.ts

@@ -103,6 +103,10 @@ export function initializeAndWatchThemeColors(callback?: () => void) {
 			'--graph-panel-bg',
 			isLightTheme ? darken(backgroundColor, 5) : lighten(backgroundColor, 5),
 		);
+		bodyStyle.setProperty(
+			'--graph-panel-bg2',
+			isLightTheme ? darken(backgroundColor, 10) : lighten(backgroundColor, 10),
+		);
 		bodyStyle.setProperty('--graph-theme-opacity-factor', isLightTheme ? '0.5' : '1');
 
 		// alert colors