perf: Defer fonts.css and variables.css, inline critical CSS

- Add @font-face declarations to critical-bootstrap.css inline
- Add critical CSS variables (colors, fonts) inline
- Defer fonts.css (utilities only, @font-face inline)
- Defer variables.css (critical vars inline)

Now only style.css is render-blocking (~19KB)
All other CSS deferred with media=print + onload

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

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

Assets/css/critical-bootstrap.css

@@ -14,6 +14,60 @@
  * @see Shared/Infrastructure/Services/CriticalBootstrapService.php
  */
 
+/* ==========================================================================
+   CRITICAL FONTS (Poppins - LCP optimization)
+   ========================================================================== */
+@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 {
+    /* 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;
+    --color-navy-medium: #1e3a5f;
+    --color-orange-primary: #FF8600;
+    --color-orange-hover: #e67a00;
+    --bs-primary: #0d6efd;
+    --bs-white: #fff;
+    --bs-body-color: #212529;
+    --bs-body-bg: #fff;
+    --bs-link-color: #0d6efd;
+    --bs-link-hover-color: #0a58ca;
+
+    /* Spacing */
+    --bs-gutter-x: 1.5rem;
+}
+
 /* ==========================================================================
    BOX SIZING & RESETS (Bootstrap Reboot crítico)
    ========================================================================== */

Inc/enqueue-scripts.php

@@ -25,8 +25,10 @@ if (!defined('ABSPATH')) {
  * @updated 1.0.23 - Bootstrap diferido gracias a critical-bootstrap.css
  */
 define('ROI_DEFERRED_CSS', [
-    // Bootstrap (diferido - critical inline via CriticalBootstrapService)
-    'roi-bootstrap',
+    // Critical CSS inline - estos archivos se difieren
+    'roi-fonts',      // @font-face inline en critical-bootstrap.css
+    'roi-bootstrap',  // Critical inline via CriticalBootstrapService
+    'roi-variables',  // Variables ahora inline en critical CSS
     // Componentes específicos (below the fold)
     'roi-badges',
     'roi-pagination',
@@ -82,15 +84,18 @@ add_filter('style_loader_tag', 'roi_add_deferred_css_onload', 10, 2);
  * - Mejorar rendimiento (sin requests externos)
  * - Cumplimiento GDPR (sin tracking de Google)
  * - Evitar bloqueo de renderizado
+ *
+ * NOTA: @font-face críticos están inline en critical-bootstrap.css
+ * Este archivo ahora es DIFERIDO (solo utilidades de texto)
  */
 function roi_enqueue_fonts() {
-    // Fonts CSS local con @font-face para Poppins self-hosted
+    // Fonts CSS local - DIFERIDO (critical @font-face inline)
     wp_enqueue_style(
         'roi-fonts',
         get_template_directory_uri() . '/Assets/css/css-global-fonts.css',
         array(),
-        '1.1.0', // Bump version: self-hosted fonts
-        'all'
+        '1.1.1', // Bump version: deferred loading
+        'print'  // DIFERIDO - @font-face inline en critical CSS
     );
 }
 
@@ -135,13 +140,14 @@ function roi_enqueue_bootstrap() {
         'print'
     );
 
-    // Variables CSS del Template RDash (NIVEL 1 - BLOQUEANTE - Issue #48)
+    // Variables CSS del Template RDash - DIFERIDO
+    // Variables críticas inline en critical-bootstrap.css
     wp_enqueue_style(
         'roi-variables',
         get_template_directory_uri() . '/Assets/css/css-global-variables.css',
         array('roi-bootstrap'),
         ROI_VERSION,
-        'all'
+        'print'  // DIFERIDO - variables críticas inline
     );
 
     // Bootstrap JS Bundle - in footer with defer