$fn=64;

// --- Parameters ---
// A5 paper width is 148mm. 152mm allows for a rigid acrylic sleeve or laminated card.
insert_width = 152;      
insert_thickness = 3.5;  
slot_depth = 25;         

base_width = 170;        
base_depth = 55;         
base_height = 35;        
corner_radius = 5;       

// --- Modules ---
module rounded_rect(w, d, h, r) {
    hull() {
        for(x = [-w/2+r, w/2-r]) {
            for(y = [-d/2+r, d/2-r]) {
                translate([x, y, 0]) cylinder(r=r, h=h);
            }
        }
    }
}

// --- Main Geometry ---
difference() {
    // Main base body with a tapered profile for stability
    hull() {
        // Bottom footprint
        rounded_rect(base_width, base_depth, 2, corner_radius);
        
        // Top profile (narrower for a sleek look)
        translate([0, 0, base_height - 2])
            rounded_rect(base_width - 10, base_depth - 25, 2, corner_radius);
    }

    // Vertical slot for the A5 insert
    // Extended 1mm upwards to prevent Z-fighting and ensure a manifold cut
    translate([-insert_width/2, -insert_thickness/2, base_height - slot_depth])
        cube([insert_width, insert_thickness, slot_depth + 1]);
}