One-page website - stretch ceilings

HTML & CSS
Job 1 of 3
landing page for a company that installs stretch ceilings turnkey in Poland. Premium dark design, three language versions (UA / PL), cost calculator, portfolio of real projects with a filter, application form and pop-up window, integration with WhatsApp and call button.

Stack
HTML5 — semantic markup, one file for each language
CSS3 — custom styles (CSS variables, Flexbox, Grid), responsive for mobile/tablet/desktop, animations (reveal on scroll, highlight on button, hover effects)
JavaScript (vanilla) — without frameworks: calculator, portfolio filtering by tabs, modal window, mobile menu, IntersectionObserver for animations
SEO — meta tags, Open Graph, Schema.org (LocalBusiness), hreflang for language versions
Python (for service) — script translate.py generates UA/PL versions from RU, plus Pillow + scipy for image processing (background removal from screen estimates)