Reduce bin file size while using lvgl

i am using es32s3 8MB rom and 8MB flash but spiffs shows only 1.4MB available, i need to do ota to upgrade firmware but my firmware already 1.3MB
Here what i have done:
1.comment the fonts in lv_conf.h i did not used .
2.comment the widgets i did not used in lv_conf.h.
3.comment some components i did not used in lv_conf.h.

After above works ,i still see the font files i commented above is build/ folder and the .bin file size not change(using vscode)

Any advices can help me to reduce the bin file size ?
Thanks a lot!