$fn=64;

// Parametric variables
panel_length = 100;      // Length of each leg of the L-shape
panel_height = 110;      // Total height of the corner panel
panel_thickness = 5;     // Thickness of the main walls

rail_protrusion = 5;     // How far the rails stick out from the inner wall
rail_thickness = 3;      // Vertical thickness of each rail
rail_slot_gap = 5;       // Gap between the two rails in a single pair

num_pairs = 3;           // Number of rail pairs per leg
pair_spacing = 30;       // Vertical distance between the start of each pair
first_pair_z = 15;       // Z offset for the lowest rail pair

union() {
    // Main L-shaped panel base
    // X-axis leg
    cube([panel_length, panel_thickness, panel_height]);
    
    // Y-axis leg
    cube([panel_thickness, panel_length, panel_height]);

    // 3+3 Rail Pairs
    for (i = [0 : num_pairs - 1]) {
        z_base = first_pair_z + i * pair_spacing;
        z_top_rail = z_base + rail_thickness + rail_slot_gap;

        // --- X-axis leg rails ---
        // Bottom rail of the pair
        translate([panel_thickness, panel_thickness, z_base])
            cube([panel_length - panel_thickness, rail_protrusion, rail_thickness]);
        // Top rail of the pair
        translate([panel_thickness, panel_thickness, z_top_rail])
            cube([panel_length - panel_thickness, rail_protrusion, rail_thickness]);

        // --- Y-axis leg rails ---
        // Bottom rail of the pair
        translate([panel_thickness, panel_thickness, z_base])
            cube([rail_protrusion, panel_length - panel_thickness, rail_thickness]);
        // Top rail of the pair
        translate([panel_thickness, panel_thickness, z_top_rail])
            cube([rail_protrusion, panel_length - panel_thickness, rail_thickness]);
    }
}