Tweaking and developing an Online Shopify Store

HUGE POTENTIAL FOR A LOT OF ONGOING WORK We are seeking the expertise of a Junior level Web Developer with extensive knowledge of JavaScript - added bonus if you have Shopify experience. Current project: Looking for someone to create an additional sticky header for my Shopify Store. It requires knowledge of CSS, HTML and JavaScript There is an existing header which will be the header when page loads but want it to scroll away and when the page has scrolled down enough for it to disappear I want a new smaller header only with the navigation, logo and cart button to slide down into view. There will be bugs as you will need to sort the margin and padding at the bottom of the content area, just before the footer.