feat(site): Comunidade section with Instagram posts the gym was tagged in

Per-gym Graph API /tags fetch with file cache and local thumbnails, section after the gallery, navbar link and admin page (Gestão > Site).

site/assets/css/style.css

@@ -2687,6 +2687,7 @@ h3.contact-title {
    4.5:1), so those use the ink green; dark sections keep the bright accent. */
 .feature-section .section-eyebrow,
 .gallery-section .section-eyebrow,
+.community-section .section-eyebrow,
 .service-section .section-eyebrow,
 .schedule-section .section-eyebrow,
 .workhours-section .section-eyebrow {
@@ -4953,3 +4954,70 @@ a:where(:not(.site-btn, .gym-switch-btn, .gal-link, .skip-link, .splide__arrow,
 h1, h2,
 .navbar-brand img,
 .gym-switch-logo { filter: url(#pt-noise); }
+
+/* ── Comunidade (Instagram posts the gym was tagged in, site/index.php) ── */
+.community-section {
+  padding: 80px 0 70px;
+  background: var(--fitme-white);
+}
+
+.community-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(min(220px, 45%), 1fr));
+  gap: 12px;
+  margin: 0;
+}
+
+.community-post {
+  position: relative;
+  display: block;
+  aspect-ratio: 1;
+  overflow: hidden;
+  border-radius: var(--fitme-radius);
+  background: var(--fitme-surface-2);
+}
+
+.community-post img {
+  width: 100%;
+  height: 100%;
+  object-fit: cover;
+  transition: transform .4s ease;
+}
+
+.community-type {
+  position: absolute;
+  top: 10px;
+  right: 10px;
+  color: #fff;
+  text-shadow: 0 1px 4px rgba(var(--fitme-dark-rgb), .6);
+}
+
+.community-user {
+  position: absolute;
+  inset: auto 0 0;
+  padding: 28px 12px 10px;
+  color: #fff;
+  font-size: .85rem;
+  font-weight: 700;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  background: linear-gradient(transparent, rgba(var(--fitme-dark-rgb), .75));
+  opacity: 0;
+  transition: opacity var(--fitme-transition);
+}
+
+.community-post:hover img,
+.community-post:focus-visible img { transform: scale(1.05); }
+
+.community-post:hover .community-user,
+.community-post:focus-visible .community-user { opacity: 1; }
+
+/* Touch screens have no hover: keep the @user visible. */
+@media (hover: none) {
+  .community-user { opacity: 1; }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .community-post img { transition: none; }
+}