3.9

Summaries added — every column in COL_DESCRIPTIONS got a short (1–2 sentences) and a link to its reference row. Full desc text kept intact for the day-tab metric labels.
Popup rewired — renders the summary plus a "More about this column →" link, opening in a new tab.
Link styling — .col-info-more pinned below the summary so it stays visible if the text scrolls; centred on mobile with the rest.
Anchors on the reference page — 35 row ids in columns.html, one per column key.
New "Rows" row — the hour/interval header had a popup but no matching row on the reference page; added.
Landing highlight — tr:target gets a gold bar and tint, with scroll offset so the nav doesn't cover it.

assets/css/table.css

@@ -1360,6 +1360,17 @@
   margin-top: 2px;
 }
 
+/* Stands in for the unit when the column has no data for the selected day —
+   currently only AQI and Pollen, which CAMS stops forecasting before the
+   14-day table runs out. Muted and italic so it reads as an absence, not a
+   value. The cells carry the full explanation as a title. */
+.utci-table th .col-unit--none {
+  color: #a89880;
+  font-style: italic;
+  text-transform: none;
+  letter-spacing: 0.02em;
+}
+
 /* Environment modifier badge — shown in SunSoak th when non-default env active */
 .col-env-badge {
   display: block;
@@ -1588,6 +1599,23 @@
   overflow-y: auto; /* scrolls when text exceeds max-height cap */
   flex: 1 1 auto;
 }
+/* "More about this column" deep-link to the reference page. Sits below the
+   summary and never shrinks, so it stays visible if the summary scrolls. */
+.col-info-more {
+  display: block;
+  flex: 0 0 auto;
+  margin-top: 8px;
+  font-family: Manrope, sans-serif;
+  font-size: 11px;
+  font-weight: 700;
+  color: #b07d1e;
+  text-decoration: none;
+}
+.col-info-more:hover,
+.col-info-more:focus-visible {
+  color: #8a5f12;
+  text-decoration: underline;
+}
 .col-info-close {
   position: absolute;
   top: 6px;
@@ -1813,7 +1841,8 @@
 /* ── POPUP — mobile centre-alignment ───────────────────────────────── */
 @media (max-width: 640px) {
   .col-info-title,
-  .col-info-desc {
+  .col-info-desc,
+  .col-info-more {
     text-align: center;
   }
 }