https://harry-su-blog.com/blog A blog recording my coding and climbing journey zh-TW undefined (Harry) undefined (Harry) Sun, 08 Nov 2026 13:00:00 GMT https://harry-su-blog.com/blog/2026/11/08/css-background-lcp-webp-preload https://harry-su-blog.com/blog/2026/11/08/css-background-lcp-webp-preload 記錄一次首頁 CSS 背景圖的 LCP 優化：將 PNG 改成 WebP、透過 SSR preload 提早下載，並釐清 Lighthouse headline LCP 與 observed breakdown 為何可能相差十幾秒。 Sun, 08 Nov 2026 13:00:00 GMT undefined (Harry) web-vitalslcpwebplighthouseperformance