feat: VivesPOS landing on Winter CMS 1.2 — theme + plugin + Dockerfile

- Base: wintercms/winter branch 1.2 (full framework)
- Theme vivespos: Canvas 7 + Bootstrap 5 CDN, custom CSS
- Layout: deferred GTM/GA4 tracking, JSON-LD SoftwareApplication
- Partials: hero (offline-first), features, modes (offline/nube toggle),
  screenshots, pricing (3 planes), comparison, FAQ, CTA
- Plugin VivesPOS.Site with ContactForm
- Dockerfile: PHP 8.2 Apache, port 80, healthcheck
- Added winter/wn-pages, blog, sitemap, seo plugins
- Active theme set to vivespos

modules/system/assets/ui/less/site.utility.less

@@ -0,0 +1,145 @@
+//
+// Utility classes
+// --------------------------------------------------
+
+
+// Floats
+// -------------------------
+
+.clearfix {
+    .clearfix();
+}
+.center-block {
+    .center-block();
+}
+.pull-right {
+    float: right !important;
+}
+.pull-left {
+    float: left !important;
+}
+
+
+// Toggling content
+// -------------------------
+
+.hide {
+    display: none !important;
+}
+.show {
+    display: block !important;
+}
+.invisible {
+    visibility: hidden;
+}
+.text-hide {
+    .text-hide();
+}
+
+// Hide from screenreaders and browsers
+//
+// Credit: HTML5 Boilerplate
+
+.hidden {
+    display: none !important;
+    visibility: hidden !important;
+}
+
+// For Affix plugin
+// -------------------------
+
+.affix {
+    position: fixed;
+}
+
+//
+// Responsive: Utility classes
+// --------------------------------------------------
+
+// IE10 in Windows (Phone) 8
+//
+// Support for responsive views via media queries is kind of borked in IE10, for
+// Surface/desktop in split view and for Windows Phone 8. This particular fix
+// must be accompanied by a snippet of JavaScript to sniff the user agent and
+// apply some conditional CSS to *only* the Surface/desktop Windows 8. Look at
+// our Getting Started page for more information on this bug.
+//
+// For more information, see the following:
+//
+// Issue: https://github.com/twbs/bootstrap/issues/10497
+// Docs: http://getbootstrap.com/getting-started/#browsers
+// Source: http://timkadlec.com/2012/10/ie10-snap-mode-and-responsive-design/
+
+@-ms-viewport {
+    width: device-width;
+}
+
+
+// Visibility utilities
+.visible-xs,
+.visible-sm,
+.visible-md,
+.visible-lg {
+    .responsive-invisibility();
+}
+
+.visible-xs {
+    @media (max-width: @screen-xs-max) {
+        .responsive-visibility();
+    }
+}
+.visible-sm {
+    @media (min-width: @screen-sm-min) and (max-width: @screen-sm-max) {
+        .responsive-visibility();
+    }
+}
+.visible-md {
+    @media (min-width: @screen-md-min) and (max-width: @screen-md-max) {
+        .responsive-visibility();
+    }
+}
+.visible-lg {
+    @media (min-width: @screen-lg-min) {
+        .responsive-visibility();
+    }
+}
+
+.hidden-xs {
+    @media (max-width: @screen-xs-max) {
+        .responsive-invisibility();
+    }
+}
+.hidden-sm {
+    @media (min-width: @screen-sm-min) and (max-width: @screen-sm-max) {
+        .responsive-invisibility();
+    }
+}
+.hidden-md {
+    @media (min-width: @screen-md-min) and (max-width: @screen-md-max) {
+        .responsive-invisibility();
+    }
+}
+.hidden-lg {
+    @media (min-width: @screen-lg-min) {
+        .responsive-invisibility();
+    }
+}
+
+
+// Print utilities
+//
+// Media queries are placed on the inside to be mixin-friendly.
+
+.visible-print {
+    .responsive-invisibility();
+
+    @media print {
+        .responsive-visibility();
+    }
+}
+
+.hidden-print {
+    @media print {
+        .responsive-invisibility();
+    }
+}