Front-end micro task (paid test) + long-term collaboration (HTML/CSS/JS)

We need a front-end developer for ongoing small improvements across a few websites.
First step is a paid micro test task on www.izradafotografija.rs:

Test task: Mobile “Install our app” slide-in (bottom banner)

Show only on mobile
Detect platform: Android → Google Play, iOS → App Store
Has close button (X)
If closed, do not show again for 7 days (localStorage/cookie)
Should not overlap existing sticky/bottom UI (use safe spacing)
Clean, minimal CSS/JS, easy to include globally (header/footer partial)

Please include in your proposal:

Estimated time to complete this task
A link to your portfolio or similar work
Your preferred rate for future work (hourly or fixed per task)

Long-term tasks: landing page improvements, UI/UX tweaks, product list/detail page refinements.

We attached a ZIP static snapshot of the homepage (HTML/CSS/JS/assets) so you can work locally without backend setup.
You can open it with any local server (e.g. VS Code Live Server).

Deliverables: working implementation + short note where you added code and how it’s included site-wide.

“Please start your proposal with: SLIDE-IN FOR APP” so I know you read the project details