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/icon.close.less

@@ -0,0 +1,33 @@
+//
+// Close icons
+// --------------------------------------------------
+
+.close {
+    float: right;
+    font-size: (@font-size-base * 1.5);
+    font-weight: @close-font-weight;
+    line-height: 1;
+    color: @close-color;
+    text-shadow: @close-text-shadow;
+    font-family: sans-serif;
+    .opacity(.2);
+
+    &:hover,
+    &:focus {
+        color: @close-color;
+        text-decoration: none;
+        cursor: pointer;
+        .opacity(.5);
+    }
+
+    // Additional properties for button version
+    // iOS requires the button element instead of an anchor tag.
+    // If you want the anchor version, it requires `href="#"`.
+    button& {
+        padding: 0;
+        cursor: pointer;
+        background: transparent;
+        border: 0;
+        -webkit-appearance: none;
+    }
+}