From de5564b19f6364a36e5de46476409b408125e17b Mon Sep 17 00:00:00 2001
From: rohow <admin@dev.cm>
Date: Fri, 30 Jan 2026 18:17:12 +0800
Subject: [PATCH] feat(dividing): sticky

---
 src/alpine/header-dividing.ts          | 35 +++++++++++++++++++
 src/alpine/{menu.ts => header-menu.ts} |  2 +-
 src/main.ts                            |  6 ++--
 src/styles/header.scss                 | 48 +++++++++++++++++++++++---
 templates/modules/header.html          |  6 ++--
 5 files changed, 88 insertions(+), 9 deletions(-)
 create mode 100644 src/alpine/header-dividing.ts
 rename src/alpine/{menu.ts => header-menu.ts} (76%)

diff --git a/src/alpine/header-dividing.ts b/src/alpine/header-dividing.ts
new file mode 100644
index 0000000..a164afa
--- /dev/null
+++ b/src/alpine/header-dividing.ts
@@ -0,0 +1,35 @@
+export const headerDividing = () => ({
+  isSticky: false,
+  $el: null as HTMLElement | null,
+  _observer: null as IntersectionObserver | null,
+
+  init() {
+    const centerEl = this.$el as HTMLElement;
+    if (!centerEl) return;
+
+    const header = centerEl.closest('.header') as HTMLElement;
+
+    if (!header) return;
+
+    // 直接观察 header 元素本身
+    this._observer = new IntersectionObserver(
+      (entries) => {
+        const entry = entries[0];
+        this.isSticky = entry.boundingClientRect.top < 0 && !entry.isIntersecting;
+      },
+      {
+        threshold: 0, // 只要有任何部分离开就触发
+        rootMargin: '0px' // 无偏移
+      }
+    );
+
+    this._observer.observe(header);
+  },
+
+  destroy() {
+    if (this._observer) {
+      this._observer.disconnect();
+      this._observer = null;
+    }
+  }
+});
diff --git a/src/alpine/menu.ts b/src/alpine/header-menu.ts
similarity index 76%
rename from src/alpine/menu.ts
rename to src/alpine/header-menu.ts
index c6167df..6b79901 100644
--- a/src/alpine/menu.ts
+++ b/src/alpine/header-menu.ts
@@ -3,7 +3,7 @@ interface MenuState {
   handleToggleMenu(): void;
 }
 
-export const menu = (): MenuState => ({
+export const headerMenu = (): MenuState => ({
   isOpen: false,
 
   handleToggleMenu() {
diff --git a/src/main.ts b/src/main.ts
index f71aaf3..d1d0ffe 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -5,18 +5,20 @@ import "./styles/font-pixel.scss";
 import Alpine from 'alpinejs'
 import {upvote} from './alpine/upvote'
 import {themeMode} from './alpine/theme-mode'
-import {menu} from './alpine/menu'
 import {postLineNum} from './alpine/post-line-num'
 import {postToc} from './alpine/post-toc'
+import {headerDividing} from './alpine/header-dividing'
+import {headerMenu} from './alpine/header-menu'
 import {typewriterEffect} from './utils'
 
 window.Alpine = Alpine
 
 Alpine.data('upvote', upvote)
 Alpine.data('themeMode', themeMode)
-Alpine.data('menu', menu)
 Alpine.data('postLineNum', postLineNum)
 Alpine.data('postToc', postToc)
+Alpine.data('headerMenu', headerMenu)
+Alpine.data('headerDividing', headerDividing)
 
 Alpine.start()
 
diff --git a/src/styles/header.scss b/src/styles/header.scss
index 52850fc..85b8168 100644
--- a/src/styles/header.scss
+++ b/src/styles/header.scss
@@ -11,12 +11,21 @@
     justify-content: space-between;
   }
 
+  &__center {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    flex: 1;
+  }
+
   .dividing {
     flex: 1;
     display: block;
     width: 100%;
     height: 25px;
     position: relative;
+    --dash-spacing: 10px;
+    --dash-width: 2px;
 
     // 虚线背景层 - 带遮罩
     &::before {
@@ -29,11 +38,11 @@
       background: repeating-linear-gradient(
                       90deg,
                       var(--foreground),
-                      var(--foreground) 2px,
+                      var(--foreground) var(--dash-width),
                       transparent 0,
-                      transparent 10px
+                      transparent var(--dash-spacing)
       );
-      background-size: 10px 100%;
+      background-size: var(--dash-spacing) 100%;
       animation: line-flow 3s linear infinite;
 
       // 遮罩层实现虚线淡入淡出效果
@@ -73,6 +82,37 @@
       animation: scan-line 5s ease-in-out infinite;
       pointer-events: none;
       z-index: 10;
+      transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
+    }
+
+    &.sticky {
+      position: fixed;
+      top: 0;
+      left: 0;
+      width: 100%;
+      height: 5px;
+      z-index: 100;
+      --dash-spacing: 6px;
+      --dash-width: 2px;
+      background: var(--background);
+      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
+
+      &::before {
+        animation: line-flow 1.5s linear infinite;
+        mask-image: none;
+        -webkit-mask-image: none;
+        top: calc(50% - 1px);
+        height: 2px;
+      }
+
+      &::after {
+        animation: scan-line 2.5s ease-in-out infinite;
+        opacity: 0.6;
+        filter: blur(3px);
+        // 调整扫描线高度以适应 5px 容器
+        height: 200%;
+        width: 25%;
+      }
     }
   }
 
@@ -82,7 +122,7 @@
       background-position: 0 0;
     }
     100% {
-      background-position: 10px 0;
+      background-position: var(--dash-spacing) 0;
     }
   }
 
diff --git a/templates/modules/header.html b/templates/modules/header.html
index 31c398c..5d674ec 100644
--- a/templates/modules/header.html
+++ b/templates/modules/header.html
@@ -5,7 +5,9 @@
         <img class="icon" th:if="${not #strings.isEmpty(theme.config.basic.logo)}" th:src="${theme.config.basic.logo}" alt="Logo" />
         <div class="text"  th:if="${not #strings.isEmpty(theme.config.basic.title)}" th:text="${theme.config.basic.title}"></div>
       </a>
-      <div class="dividing"></div>
+      <div class="header__center" x-data="headerDividing()">
+        <div class="dividing" :class="{ 'sticky': isSticky }"></div>
+      </div>
       <button
         type="button"
         class="button"
@@ -47,7 +49,7 @@
     </div>
     <nav class="menu">
       <ul th:if="${menu != null} and ${not #lists.isEmpty(menu.menuItems)}" class="menu__inner">
-        <li th:each="menuItem : ${menu.menuItems}" x-data="menu()" @mouseenter="handleToggleMenu()" @mouseleave="handleToggleMenu()">
+        <li th:each="menuItem : ${menu.menuItems}" x-data="headerMenu()" @mouseenter="handleToggleMenu()" @mouseleave="handleToggleMenu()">
           <a
             class="text-gray-600 hover:text-blue-600"
             th:href="${menuItem.status.href}"