I did that:

"First, you should go to the Template Manager -> Advanced -> Please check 'Development with lesscss', if you choose 'Yes', you can override css code on your_site\templates\sj_template\less\your_css.less , if you choose 'No', you can use file your_site\templates\sj_template\css\your_css.css"

I created file your_css.css and performed modifications in it. These adjustments but does not appear on the site. File your_css.css is inserted in "your_site\templates\sj_template\css\your_css.css". And in this way Template Manager -> Advanced -> Please check i choosed "No". Thank you for advice.