/* i18n.css — FOUC protection for client-side language switching. See docs/superpowers/specs/2026-07-01-i18n-zh-en-toggle-design.md §C. Strategy: i18n.js (loaded synchronously in ) adds the .i18n-translating class to BEFORE first paint when the user's saved language is non-zh. body fades in once translations are applied. If i18n.js fails to load or JS is disabled, no one adds the class, so body stays opacity:1 and Chinese fallback is fully visible. */ html.i18n-translating body { opacity: 0; } html body { opacity: 1; transition: opacity 80ms ease; } /* English mode: render all body text in Poppins. Per-character fallback handles any stray CJK (e.g., ICP filing string) via Source Han Sans SC. */ html[lang="en"] body { font-family: "Poppins", "Source Han Sans SC", -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }