feat(Section): add a styickyTitle feature and change the section layout

src/shared/ui/Section/Section.svelte

@@ -56,13 +56,40 @@ interface Props extends Omit<HTMLAttributes<HTMLElement>, 'title'> {
     /**
      * Snippet for the section content
      */
-    children?: Snippet;
+    content?: Snippet<[{ className?: string }]>;
+    /**
+     * When true, the title stays fixed in view while
+     * scrolling through the section content.
+     */
+    stickyTitle?: boolean;
+    /**
+     * Top offset for sticky title (e.g. header height).
+     * @default '0px'
+     */
+    stickyOffset?: string;
 }
 
-const { class: className, title, icon, description, index = 0, onTitleStatusChange, id, children }: Props = $props();
+const {
+    class: className,
+    title,
+    icon,
+    description,
+    index = 0,
+    onTitleStatusChange,
+    id,
+    content,
+    stickyTitle = false,
+    stickyOffset = '0px',
+}: Props = $props();
 
 let titleContainer = $state<HTMLElement>();
-const flyParams: FlyParams = { y: 0, x: -50, duration: 300, easing: cubicOut, opacity: 0.2 };
+const flyParams: FlyParams = {
+    y: 0,
+    x: -50,
+    duration: 300,
+    easing: cubicOut,
+    opacity: 0.2,
+};
 
 // Track if the user has actually scrolled away from view
 let isScrolledPast = $state(false);
@@ -72,18 +99,21 @@ $effect(() => {
         return;
     }
     let cleanup: ((index: number) => void) | undefined;
-    const observer = new IntersectionObserver(entries => {
-        const entry = entries[0];
-        const isPast = !entry.isIntersecting && entry.boundingClientRect.top < 0;
+    const observer = new IntersectionObserver(
+        entries => {
+            const entry = entries[0];
+            const isPast = !entry.isIntersecting && entry.boundingClientRect.top < 0;
 
-        if (isPast !== isScrolledPast) {
-            isScrolledPast = isPast;
-            cleanup = onTitleStatusChange?.(index, isPast, title, id);
-        }
-    }, {
-        // Set threshold to 0 to trigger exactly when the last pixel leaves
-        threshold: 0,
-    });
+            if (isPast !== isScrolledPast) {
+                isScrolledPast = isPast;
+                cleanup = onTitleStatusChange?.(index, isPast, title, id);
+            }
+        },
+        {
+            // Set threshold to 0 to trigger exactly when the last pixel leaves
+            threshold: 0,
+        },
+    );
 
     observer.observe(titleContainer);
     return () => {
@@ -94,20 +124,32 @@ $effect(() => {
 </script>
 
 <section
-    id={id}
+    {id}
     class={cn(
-        'flex flex-col',
+        'col-span-2 grid grid-cols-subgrid',
+        stickyTitle ? 'gap-x-6 sm:gap-x-8 md:gap-x-10 lg:gap-x-12' : 'grid-rows-[max-content_1fr]',
         className,
     )}
     in:fly={flyParams}
     out:fly={flyParams}
 >
-    <div class="flex flex-col gap-2 sm:gap-3" bind:this={titleContainer}>
+    <div
+        bind:this={titleContainer}
+        class={cn(
+            'flex flex-col gap-2 sm:gap-3',
+            stickyTitle && 'self-start',
+        )}
+        style:position={stickyTitle ? 'sticky' : undefined}
+        style:top={stickyTitle ? stickyOffset : undefined}
+    >
         <div class="flex items-center gap-2 sm:gap-3">
             {#if icon}
-                {@render icon({ className: 'size-3 sm:size-4 stroke-foreground stroke-1 opacity-60' })}
+                {@render icon({
+    className: 'size-3 sm:size-4 stroke-foreground stroke-1 opacity-60',
+})}
                 <div class="w-px h-2.5 sm:h-3 bg-border-subtle"></div>
             {/if}
+
             {#if description}
                 <Footnote>
                     {#snippet render({ class: className })}
@@ -129,5 +171,9 @@ $effect(() => {
         {/if}
     </div>
 
-    {@render children?.()}
+    {@render content?.({
+    className: stickyTitle
+        ? 'row-start-2 col-start-2'
+        : 'row-start-2 col-start-2',
+})}
 </section>