replace dead Tailwind classes in shop pages with custom CSS

Coming soon page was unstyled after Tailwind removal — replaced
utility classes with proper component CSS. Also removed dead h-full
classes from shop_root layout, adding height: 100% to the shop reset.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

assets/css/shop/components.css

@@ -2480,4 +2480,31 @@
     .product-grid[data-columns="3"] { grid-template-columns: repeat(3, 1fr); }
     .product-grid[data-columns="4"] { grid-template-columns: repeat(4, 1fr); }
   }
+
+  /* ── Coming soon ── */
+
+  .coming-soon {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    min-height: 100vh;
+    min-height: 100dvh;
+    padding-inline: 1.5rem;
+    text-align: center;
+  }
+
+  .coming-soon-title {
+    font-family: var(--t-font-heading);
+    font-weight: var(--t-heading-weight);
+    letter-spacing: var(--t-heading-tracking);
+    color: var(--t-text-primary);
+    font-size: clamp(1.875rem, 5vw, 2.25rem);
+    line-height: 1.2;
+  }
+
+  .coming-soon-message {
+    margin-top: 1rem;
+    font-size: 1.125rem;
+    color: var(--t-text-secondary);
+  }
 }

assets/css/shop/reset.css

@@ -13,12 +13,14 @@
   }
 
   html {
+    height: 100%;
     -webkit-text-size-adjust: 100%;
     -moz-text-size-adjust: 100%;
     text-size-adjust: 100%;
   }
 
   body {
+    height: 100%;
     line-height: 1.5;
     -webkit-font-smoothing: antialiased;
   }
@@ -78,6 +80,11 @@
     cursor: pointer;
   }
 
+  /* Full-height shop root */
+  .shop-root {
+    height: 100%;
+  }
+
   /* LiveView wrapper divs are layout-invisible */
   [data-phx-session],
   [data-phx-teleported-src] {