# Theme base (legacy vs. next)

By default, any custom theme will be based on the legacy light theme. To change the TriliumNext theme instead, add the `#appThemeBase=next` attribute onto the existing theme. The `appTheme` attribute must also be present.

When `appThemeBase` is set to `next` it will use the “TriliumNext (auto)” theme. Any other value is ignored and will use the legacy white theme instead.

## Overrides

Do note that the TriliumNext theme has a few more overrides than the legacy theme, so you might need to suffix `!important` if the style changes are not applied.

    :root {
    	--launcher-pane-background-color: #0d6efd !important;
    }