revert: restaurar Poppins - parpadeo de iconos persiste

Revertir cambio a system fonts porque el parpadeo de iconos
(Bootstrap Icons) sigue presente, haciendo el cambio innecesario.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Assets/Css/critical-bootstrap.css

@@ -5,7 +5,7 @@
  * NO contiene CSS personalizado (ese va en critical-custom-temp.css - TIPO 3).
  *
  * Componentes Bootstrap incluidos:
- * - System Fonts (CERO flash - sin @font-face externos)
+ * - Fonts (@font-face Poppins)
  * - Variables CSS (:root)
  * - Resets (box-sizing, body)
  * - Container system
@@ -30,29 +30,45 @@
  */
 
 /* ==========================================================================
-   SYSTEM FONTS - CERO Flash (sin fuentes externas)
+   CRITICAL FONTS (Poppins - LCP optimization)
 
-   Usa fuentes nativas del sistema operativo:
-   - macOS/iOS: -apple-system, BlinkMacSystemFont
-   - Windows: Segoe UI
-   - Android: Roboto
-   - Linux: Ubuntu/Cantarell
-   - Fallback: sans-serif
-
-   VENTAJAS:
-   - 0 KB descarga (fuentes ya instaladas)
-   - 0 flash/parpadeo (disponibles instantaneamente)
-   - Mejor rendimiento LCP/FCP
-   - Familiar para usuarios (fuentes nativas)
+   font-display: swap + preload = fuente carga rapido y siempre se muestra
+   size-adjust: 100.6% = fallback casi identico a Poppins (minimiza CLS)
    ========================================================================== */
+@font-face {
+    font-family: 'Poppins Fallback';
+    src: local('Arial'), local('Helvetica Neue'), local('sans-serif');
+    size-adjust: 106%;
+    ascent-override: 105%;
+    descent-override: 35%;
+    line-gap-override: 10%;
+}
+@font-face {
+    font-family: 'Poppins';
+    src: url('/wp-content/themes/roi-theme/Assets/Fonts/poppins-v24-latin-regular.woff2') format('woff2');
+    font-weight: 400;
+    font-style: normal;
+    font-display: swap;
+}
+@font-face {
+    font-family: 'Poppins';
+    src: url('/wp-content/themes/roi-theme/Assets/Fonts/poppins-v24-latin-600.woff2') format('woff2');
+    font-weight: 600;
+    font-style: normal;
+    font-display: swap;
+}
+@font-face {
+    font-family: 'Poppins';
+    src: url('/wp-content/themes/roi-theme/Assets/Fonts/poppins-v24-latin-700.woff2') format('woff2');
+    font-weight: 700;
+    font-style: normal;
+    font-display: swap;
+}
 
 :root {
-    /* System Font Stack - CERO flash garantizado */
-    --font-system: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
-                   "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans",
-                   sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
-    --font-primary: var(--font-system);
-    --bs-body-font-family: var(--font-system);
+    /* Fonts */
+    --font-primary: 'Poppins', 'Poppins Fallback', sans-serif;
+    --bs-body-font-family: 'Poppins', 'Poppins Fallback', sans-serif;
 
     /* Theme Colors (críticos para above-the-fold) */
     --color-navy-dark: #0E2337;