feat: story-journey immersive layer (progress, scene focus, floating orbs)

themes/dreamscape/assets/css/dreamscape.css

@@ -253,6 +253,121 @@ main {
     font-family: var(--font-sans);
 }
 
+/* ═══ 故事沉浸层（文章页） ═══ */
+.story-journey {
+    position: relative;
+    isolation: isolate;
+}
+
+.story-orb {
+    position: fixed;
+    pointer-events: none;
+    z-index: -1;
+    border-radius: 50%;
+    filter: blur(36px);
+    opacity: 0.35;
+    mix-blend-mode: screen;
+    transition: transform 0.2s ease-out;
+}
+
+.orb-1 {
+    width: 280px;
+    height: 280px;
+    top: 14%;
+    left: -80px;
+    background: radial-gradient(circle, rgba(123,104,238,0.42), transparent 70%);
+}
+
+.orb-2 {
+    width: 220px;
+    height: 220px;
+    top: 48%;
+    right: -60px;
+    background: radial-gradient(circle, rgba(34,211,238,0.34), transparent 72%);
+}
+
+.orb-3 {
+    width: 320px;
+    height: 320px;
+    bottom: 6%;
+    left: 24%;
+    background: radial-gradient(circle, rgba(74,144,217,0.30), transparent 72%);
+}
+
+.story-progress {
+    position: sticky;
+    top: 62px;
+    height: 4px;
+    background: rgba(123,104,238,0.18);
+    border-radius: 999px;
+    overflow: hidden;
+    margin: -1rem 0 2rem;
+    z-index: 40;
+}
+
+.story-progress-bar {
+    height: 100%;
+    width: 0%;
+    background: linear-gradient(90deg, var(--glow-purple), var(--glow-cyan));
+    box-shadow: 0 0 18px rgba(123,104,238,0.6);
+    transition: width 0.08s linear;
+}
+
+/* 场景段落：像旅程节点 */
+.article-body > p {
+    position: relative;
+    padding-left: 1.1rem;
+}
+
+.article-body > p::before {
+    content: '';
+    position: absolute;
+    left: -0.15rem;
+    top: 0.85rem;
+    width: 6px;
+    height: 6px;
+    border-radius: 50%;
+    background: var(--glow-purple);
+    box-shadow: 0 0 12px rgba(123,104,238,0.8);
+    opacity: 0.55;
+}
+
+.article-body > p.active-scene::before {
+    background: var(--glow-cyan);
+    box-shadow: 0 0 16px rgba(34,211,238,0.9);
+    opacity: 1;
+}
+
+.article-body > p.active-scene {
+    text-shadow: 0 0 18px rgba(123,104,238,0.22);
+}
+
+/* 手机端沉浸优化 */
+@media (max-width: 640px) {
+    .story-progress {
+        top: 54px;
+        margin: -0.5rem 0 1.2rem;
+    }
+    .story-orb {
+        filter: blur(26px);
+        opacity: 0.28;
+    }
+    .orb-1 { width: 180px; height: 180px; left: -60px; }
+    .orb-2 { width: 150px; height: 150px; right: -45px; }
+    .orb-3 { width: 190px; height: 190px; left: 20%; }
+}
+
+/* 降级策略：用户偏好减少动画 */
+@media (prefers-reduced-motion: reduce) {
+    .story-orb,
+    .story-progress-bar,
+    .reveal,
+    .js-ready .article-body p {
+        animation: none !important;
+        transition: none !important;
+    }
+}
+
 /* ═══ 文章页 ═══ */
 .dream-article {
     padding-top: 2rem;

themes/dreamscape/assets/js/dreamscape.js

@@ -7,6 +7,7 @@
 
     // ═══ 星空粒子系统 ═══
     const canvas = document.getElementById('starfield');
+    if (!canvas) return;
     const ctx = canvas.getContext('2d');
     let width, height, stars, nebulas;
     let animationId;
@@ -133,6 +134,55 @@
         });
     }
 
+    // ═══ 场景滚动进度 + 旅程节点高亮 ═══
+    function setupStoryJourney() {
+        const body = document.getElementById('storyBody');
+        const progress = document.getElementById('storyProgress');
+        if (!body || !progress) return;
+
+        const scenes = Array.from(body.querySelectorAll(':scope > p'));
+        if (!scenes.length) return;
+
+        const onScroll = () => {
+            const rect = body.getBoundingClientRect();
+            const total = Math.max(body.scrollHeight - window.innerHeight, 1);
+            const scrolled = Math.min(Math.max(-rect.top, 0), total);
+            const ratio = scrolled / total;
+            progress.style.width = `${(ratio * 100).toFixed(2)}%`;
+
+            let activeIndex = 0;
+            let minDistance = Infinity;
+            scenes.forEach((p, idx) => {
+                const r = p.getBoundingClientRect();
+                const d = Math.abs(r.top - window.innerHeight * 0.35);
+                if (d < minDistance) {
+                    minDistance = d;
+                    activeIndex = idx;
+                }
+            });
+            scenes.forEach((p, idx) => p.classList.toggle('active-scene', idx === activeIndex));
+        };
+
+        window.addEventListener('scroll', onScroll, { passive: true });
+        onScroll();
+    }
+
+    // ═══ 漂浮光团轻微视差 ═══
+    function setupOrbsParallax() {
+        const orbs = document.querySelectorAll('.story-orb');
+        if (!orbs.length) return;
+
+        window.addEventListener('scroll', () => {
+            const y = window.scrollY;
+            orbs.forEach((orb, i) => {
+                const factor = (i + 1) * 0.04;
+                const xShift = Math.sin(y * 0.002 + i) * 10;
+                const yShift = y * factor;
+                orb.style.transform = `translate(${xShift}px, ${yShift}px)`;
+            });
+        }, { passive: true });
+    }
+
     // ═══ 初始化 ═══
     window.addEventListener('resize', () => {
         resize();
@@ -146,6 +196,8 @@
         setupReveal();
         setupParallax();
         setupGlow();
+        setupStoryJourney();
+        setupOrbsParallax();
     });
 
 })();