Steps :
1) Upload new design template folder and file to hosting/server.
- Do NOT overwrite existing folder, just upload the new file to existing folder.
- If same name file, then rename old file by adding -old behind.

2) Test upload and open a html front page see if all image, design no missing and right click select "inspect" in chrome to check console got error.

3) (Please DON'T do this step 3, i show step 3 is just because worry you forget and stupid doing step 3).
Move files to deeper folder Eg. FROM :
test.hyperspace.today/asset/img
TO:
test.hyperspace.today/application/views/themes/defaults/assets_web/img

4) After move file at step 3, if u can't browse the page, solution is at step 5.

5) Solution for step 4 is You need to do 3 things :
a) rename file extension from .html to .php
b) Controller/Hungry create function contactus(){ to load the view from the new file contactus.php
c) config/route.php add $route['contactus'] = "hungry/contactus";

6) Focus on edit homepage now. Clone new design index.html file and rename 1 to menu-2.php and upload it to server.

7) at Controller/Hungry.php edit function menu() load view to menu-2.php (comment out the original load view code)

8) Replace the new design content to real content. Eg, username, sidebar menu, wallet name and amount.

Bug : Bootstrap Modal cannot close.
make sure dont have repeating the same id of div in two files :
1) modal_view_tree_member_data.php
2) dashboard.php
Then if using bootstrap v5 instead of v4, solution :
New Way <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button> Old Way <button type="button" class="btn-close" data-dismiss="modal" aria-label="Close"></button>
----------------------------------
Bug : Boostrap 5 Modal cannot open.
Solution : Change data-toggle="modal" data-target="#lostpassword" TO :
data-bs-toggle="modal" data-bs-target="#lostpassword"

Cannot find jquery function or javascript function is from which .js file?
Solution : right click the webpage, select "Page Source", then click each .js link to open it. Then press CTRL + F to find the keyword.