Fix Rounding & Mobile Menu

I run a small bike-repair shop in Utrecht and host our plain-HTML website from a private GitHub repo deployed on Netlify. Two annoyances are starting to scare customers away and I’d like them solved quickly, via a clean pull request to the repo.

1. Price-estimate math
The JavaScript that totals selected services sometimes spits out numbers like €37.849999999999994. I need the total to appear always rounded to exactly two cents, for example €37.85, with no lingering floating-point oddities.

2. Mobile navigation
On both iPhone/Safari and Android/Chrome the hamburger menu opens, but after tapping any link it stubbornly stays in place, covering the newly loaded page. The menu should close immediately once a link is tapped so the chosen page is fully visible.

Tech context
• Static HTML/CSS/vanilla JS (no frameworks)
• GitHub for version control; Netlify handles the build and deploy

Deliverables
• Updated JS that guarantees two-decimal totals across all common browsers.
• CSS/JS tweak so the mobile menu closes instantly after link activation on both iOS and Android.
• A concise README note describing what changed and why.
• All changes delivered through a GitHub pull request; I’ll merge and trigger the Netlify deploy once verified.

I can add you to the private repo as soon as we agree. Looking forward to a tidy fix that keeps my customers focused on their bikes, not my website glitches.