@* A collapsible sidebar nav section: an uppercase-eyebrow button that toggles
   the visibility of its child nav items. Mirrors the ScadaLink NavSection at
   /Users/dohertj2/Desktop/scadalink-design/src/ScadaLink.CentralUI/Components/Layout/NavSection.razor
   but uses OtOpcUa's rail-eyebrow + rail-link classes. *@

<button type="button"
        class="rail-eyebrow-toggle"
        @onclick="OnToggle"
        aria-expanded="@(Expanded ? "true" : "false")">
    <span class="rail-eyebrow-chevron">@(Expanded ? "▼" : "▶")</span>
    <span class="rail-eyebrow-label">@Title</span>
</button>
@if (Expanded)
{
    <div class="rail-section-body">
        @ChildContent
    </div>
}

@code {
    /// <summary>Section label shown in the eyebrow (e.g. "Scripting").</summary>
    [Parameter, EditorRequired]
    public string Title { get; set; } = string.Empty;

    /// <summary>Whether the section is expanded — its child links rendered.</summary>
    [Parameter]
    public bool Expanded { get; set; }

    /// <summary>Raised when the eyebrow button is clicked.</summary>
    [Parameter]
    public EventCallback OnToggle { get; set; }

    /// <summary>The section's child nav links, rendered only while expanded.</summary>
    [Parameter]
    public RenderFragment? ChildContent { get; set; }
}