Construction of stair platforms along with the removal of architectural barriers to ensure access for people with disabilities to the ground floor corridor, elevator and student bar (cafe) in the building of the Faculty of Natural Sciences of the University of Silesia in Katowice at ul. Jagiellońska 26-28 - Increasing the architectural accessibility of the University of Silesia as part of the project "DUO - University of Silesia as an accessible, universal and open university (EXPIRED)