1 files changed, 37 insertions, 0 deletions

diff --git a/src/scripts/lib/siteHeader.ts b/src/scripts/lib/siteHeader.ts
new file mode 100644
index 0000000..0d9ec43
--- /dev/null
+++ b/src/scripts/lib/siteHeader.ts
@@ -0,0 +1,37 @@
+export function mountSiteHeader() {
+        const headerEl = document.querySelector<HTMLElement>(".c-site-header");
+
+        if (headerEl) {
+                const navbarEl = headerEl?.querySelector(".o-navbar--static-white");
+                const logoEl = headerEl?.querySelector(".c-logo--static-white");
+                const buttonEls = headerEl?.querySelectorAll(".o-button--static-white");
+
+                let settings: IntersectionObserverInit;
+
+                const boundingRect = headerEl.getBoundingClientRect();
+
+                if (boundingRect.top > 0) {
+                        settings = {
+                                rootMargin: "1px 0px -100% 0px",
+                        };
+                } else {
+                        settings = {
+                                root: document.documentElement,
+                                rootMargin: "-1px 0px 0px 0px",
+                                threshold: [1],
+                        };
+                }
+
+                const observer = new IntersectionObserver(([e]) => {
+                        const scroll = e?.isIntersecting;
+                        headerEl.classList.toggle("is-scroll", scroll);
+                        navbarEl?.classList.toggle("o-navbar--static-white", !scroll);
+                        logoEl?.classList.toggle("c-logo--static-white", !scroll);
+                        for (const buttonEl of buttonEls) {
+                                buttonEl.classList.toggle("o-button--static-white", !scroll);
+                        }
+                }, settings);
+
+                observer.observe(headerEl);
+        }
+}