style(about): 调整玻璃态模糊值和光斑模糊效果

- 减小玻璃态背景的模糊半径从28px到18px
- 减少光斑元素的模糊值从80px到40px
- 优化标签云计算逻辑，使用缓存宽高避免重复查询
- 改进主题语言监听器，防止重复加载和竞态条件
- 修复标签定位计算，提高渲染性能
- 清理冗余代码和注释

css/about.css

@@ -16,7 +16,7 @@
     --glass-bg: rgba(255, 255, 255, 0.75);
     --glass-border: 1px solid rgba(255, 255, 255, 0.9);
     --glass-shadow: 0 12px 36px rgba(0, 0, 0, 0.12);
-    --glass-blur: 28px;
+    --glass-blur: 18px;
 
     --text-primary: #1f2937;
     --text-secondary: #4b5563;
@@ -88,7 +88,7 @@ body {
 
 /* Ambient Background */
 .aurora-canvas { position: fixed; inset: 0; z-index: -1; overflow: hidden; pointer-events: none; }
-.glow-spot { position: absolute; border-radius: 50%; filter: blur(80px); opacity: 0.5; animation: float 20s infinite alternate; }
+.glow-spot { position: absolute; border-radius: 50%; filter: blur(40px); opacity: 0.5; animation: float 20s infinite alternate; }
 .spot-1 { top: -10%; left: -10%; width: 50vw; height: 50vw; background: var(--bg-grad-1); }
 .spot-2 { bottom: -10%; right: -10%; width: 60vw; height: 60vw; background: var(--bg-grad-2); animation-delay: -5s; }
 .noise-layer { position: absolute; inset: 0; opacity: 0.03; background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E"); }
@@ -3169,4 +3169,4 @@ body {
 
 /* Loading Transition */
 .fade-in { animation: fadeIn 0.3s ease both; }
-@keyframes fadeIn { from { opacity: 0; transform: translateY(2px);} to { opacity: 1; transform: none;} }
+@keyframes fadeIn { from { opacity: 0; transform: translateY(2px);} to { opacity: 1; transform: none;} }