$fn = 64;

// --- Parameters ---
riser_height = 100;         // Total height of the riser (100mm)
top_diameter = 40;          // Diameter of the top platform
base_diameter = 70;         // Wide base for stability
pillar_diameter = 22;       // Central column thickness
platform_thickness = 4;     // Thickness of the top platform
base_thickness = 5;         // Thickness of the base plate
rib_height = 45;            // Height of the reinforcing ribs
rib_thickness = 4.5;        // Thickness of the ribs
num_ribs = 4;               // Number of reinforcing ribs

union() {
    // Stable Base
    cylinder(h=base_thickness, r1=base_diameter/2, r2=(base_diameter/2)-1.5);

    // Central Pillar
    cylinder(h=riser_height, r=pillar_diameter/2);

    // Top Platform
    translate([0, 0, riser_height - platform_thickness])
        cylinder(h=platform_thickness, r1=(top_diameter/2)-2, r2=top_diameter/2);

    // Reinforced Structure (Buttress Ribs)
    for (i = [0 : num_ribs - 1]) {
        rotate([0, 0, i * (360 / num_ribs)])
            translate([0, 0, base_thickness - 0.1]) // 0.1mm overlap for manifold geometry
            rotate([90, 0, 0])
            linear_extrude(height=rib_thickness, center=true)
            polygon([
                [pillar_diameter/2 - 1, 0],         // Inner bottom (overlaps pillar)
                [base_diameter/2 - 4, 0],           // Outer bottom
                [pillar_diameter/2 - 1, rib_height] // Inner top
            ]);
    }
}