mobile: per-view ≤480px rules across the CSS bundle

Adds the @media (max-width: 480px) blocks specified in the design:

- dashboard.css: indicator table hides the 'mobile-hide'-tagged
  columns (Label, Ccy, 1y, anchor, as-of), keeping Symbol / Price /
  1d / 1m. Cell padding + font shrink. Group-tab buttons get a
  bigger touch target.
- panels.css: header padding tightens, scroll-body max-height drops
  to 60vh so log/news stay above the fold in the stacked layout.
- portfolio.css: overall grid keeps 2 cols (already at 640px) with
  tighter gap; action buttons wrap; composer input goes full-width.
- log-chat.css: chat bubbles edge-to-edge, input row stacks, font-
  size:14px on form fields to avoid iOS Safari zoom-on-focus.
- news.css: row collapses to age | (title / source) — source moves
  under the title. Tag filter strip wraps.
- settings.css: form rows stack (label above input). Import picker
  becomes single-column. Buttons full-width.
- auth.css: card padding tightens to free up vertical space when the
  iOS keyboard is up. font-size:14px on inputs.
- public.css: hero headline clamp() lower bound drops to 22px; CTAs
  stack full-width; pricing tier-grid stacks.

indicators.html: tagged the secondary cells with .mobile-hide rather
than relying on positional nth-child — the anchor column is
conditional and would have shifted positions.

336 tests still pass.

app/static/css/dashboard.css

@@ -226,3 +226,42 @@
   vertical-align: middle;
   user-select: none;
 }
+
+
+/* --- Mobile (≤480px) -------------------------------------------------- */
+
+@media (max-width: 480px) {
+  /* Hide secondary indicator-table columns: Label, Ccy, 1y, anchor,
+     as-of. The cells are tagged with .mobile-hide in indicators.html;
+     this rule keeps display intent in CSS while letting the template
+     handle the conditional anchor column. Symbol / Price / 1d / 1m
+     remain — the four numbers a phone user actually wants. */
+  .dense .mobile-hide { display: none; }
+
+  /* Tighter cell padding so the four remaining columns fit
+     comfortably on a 360px viewport. */
+  .dense th, .dense td {
+    padding: 4px 6px;
+    font-size: 11px;
+  }
+  /* Symbol column gets a touch more breathing room — it's the
+     identifying anchor. */
+  .dense td.label { font-weight: 600; }
+
+  /* Group-tabs strip already has overflow-x:auto; widen the tap
+     targets so swipe-scrolling on a touchscreen feels natural. */
+  .group-tabs button {
+    padding: 8px 14px;
+    font-size: 11.5px;
+    white-space: nowrap;
+  }
+
+  /* Aggregate-read summary header tightens — stack the label above
+     the timestamp to avoid wrapping at awkward points. */
+  .ind-summary__head {
+    flex-direction: column;
+    align-items: flex-start;
+    gap: 2px;
+  }
+  .ind-summary__body { font-size: 12px; }
+}