feat: 优化文章系列导航栏的展开收缩动画与交互效果

src/routes/posts/[slug]/+page.svelte

@@ -20,6 +20,40 @@
 			: null
 	);
 
+	let isSeriesOpen = $state(true);
+	let seriesContentEl: HTMLElement | null = $state(null);
+
+	function toggleSeries(e: MouseEvent) {
+		const target = e.target as HTMLElement;
+		if (target.closest('a')) return;
+
+		const contentEl = seriesContentEl;
+		if (!contentEl) {
+			isSeriesOpen = !isSeriesOpen;
+			return;
+		}
+
+		if (isSeriesOpen) {
+			if (contentEl.style.maxHeight === 'none' || contentEl.style.maxHeight === '') {
+				contentEl.style.maxHeight = contentEl.scrollHeight + 'px';
+				void contentEl.offsetHeight;
+			}
+			contentEl.style.maxHeight = '0px';
+			isSeriesOpen = false;
+		} else {
+			isSeriesOpen = true;
+			contentEl.style.maxHeight = contentEl.scrollHeight + 'px';
+
+			const transitionEndHandler = (ev: Event) => {
+				if (ev.target === contentEl && isSeriesOpen) {
+					contentEl.style.maxHeight = 'none';
+				}
+				contentEl.removeEventListener('transitionend', transitionEndHandler);
+			};
+			contentEl.addEventListener('transitionend', transitionEndHandler);
+		}
+	}
+
 	onMount(() => {
 		const headers = document.querySelectorAll(
 			'.js-toc-content h1, .js-toc-content h2, .js-toc-content h3, .js-toc-content h4, .js-toc-content h5, .js-toc-content h6'
@@ -61,6 +95,10 @@
 			};
 		});
 
+		if (seriesContentEl && isSeriesOpen) {
+			seriesContentEl.style.maxHeight = 'none';
+		}
+
 		return () => {
 			if (hasToc) tocbot.destroy();
 		};
@@ -88,8 +126,14 @@
 			{/if}
 
 			{#if data.series && data.seriesPosts.length > 0}
-				<details class="series-nav" open>
-					<summary class="series-title" id="series-navigation-title">
+				<div class="details series-nav" class:open={isSeriesOpen}>
+					<!-- svelte-ignore a11y_click_events_have_key_events -->
+					<!-- svelte-ignore a11y_no_static_element_interactions -->
+					<div
+						class="details-summary series-title"
+						id="series-navigation-title"
+						onclick={toggleSeries}
+					>
 						<span
 							>{$page.data.aliases?.series || '系列'} -
 							<a href={resolve('/series/[slug]', { slug: data.series.slug })}>{data.series.name}</a
@@ -110,8 +154,8 @@
 								></path></svg
 							>
 						</span>
-					</summary>
-					<div class="series-content">
+					</div>
+					<div bind:this={seriesContentEl} class="details-content series-content">
 						<nav>
 							<ul>
 								{#each data.seriesPosts as seriesPost (seriesPost.id)}
@@ -142,7 +186,7 @@
 							{/if}
 						</nav>
 					</div>
-				</details>
+				</div>
 			{/if}
 			<MarkdownRenderer content={data.post.content} />
 
@@ -204,11 +248,7 @@
 		padding: 0.25rem 0.75rem;
 		background: #e6e6e6;
 		cursor: pointer;
-		list-style: none;
-	}
-
-	.series-nav .series-title::-webkit-details-marker {
-		display: none;
+		user-select: none;
 	}
 
 	/* .details-icon — 对应 DoIt .details .details-icon > svg */
@@ -222,35 +262,25 @@
 		transition: transform 0.2s ease;
 	}
 
-	.series-nav[open] .details-icon > :global(svg) {
+	.series-nav.open .details-icon > :global(svg) {
 		transform: rotate(90deg);
 	}
 
-	/* .series-content — 展开收缩动画 */
-	.series-nav .series-content {
+	/* .series-content — 展开收缩动画，与 admonition 完全一致 */
+	.series-nav .details-content {
 		font-size: 0.875rem;
 		background-color: #f5f5f5;
-		display: grid;
-		grid-template-rows: 0fr;
-		transition: grid-template-rows 0.3s ease-out;
+		max-height: 0;
 		overflow: hidden;
+		transition: max-height 0.3s ease-out;
 	}
 
-	.series-nav[open] .series-content {
-		grid-template-rows: 1fr;
-	}
-
-	.series-nav .series-content > nav {
-		min-height: 0;
-		overflow: hidden;
-	}
-
-	.series-nav .series-content > nav > ul {
+	.series-nav .details-content > nav > ul {
 		margin: 0;
 		padding: 0.4rem 1rem 0.4rem 1.8rem;
 	}
 
-	.series-nav .series-content ul {
+	.series-nav .details-content ul {
 		text-indent: -0.85rem;
 		padding-left: 0.8rem;
 		list-style: none;