diff --git a/draw_12_tilted_rects.c b/draw_12_tilted_rects.c
index 5697099..e718328 100644
--- a/draw_12_tilted_rects.c
+++ b/draw_12_tilted_rects.c
@@ -130,9 +130,9 @@ static void build_framebuffer(uint8_t *fb)
         int y1_top = (int)round(y_top    - offset);
 
         int x0_bot = (int)round(cx - x_offset);
-        int y0_bot = (int)round(y_bottom - offset);
+        int y0_bot = (int)round(y_bottom + offset);
         int x1_bot = (int)round(cx + x_offset);
-        int y1_bot = (int)round(y_bottom + offset);
+        int y1_bot = (int)round(y_bottom - offset);
 
         /* ---- draw the four sides (thick) ---- */
         draw_thick_line(fb, x0_top, y0_top, x1_top, y1_top,