highlight: remove symbol line, reduce height to 5rem

src/app.css

@@ -80,7 +80,7 @@
 /* ── Highlighted result (above grid) ──────────────────────────────────────── */
 .highlighted-result {
   /* Fixed height that never changes whether populated or empty */
-  height: 10rem;
+  height: 5rem;
   margin-bottom: 1.5rem;
   border-radius: var(--pico-border-radius, 0.25rem);
   background-color: var(--pico-card-background-color);
@@ -147,12 +147,6 @@
   font-weight: 400;
 }
 
-.highlighted-symbol {
-  font-size: clamp(0.75rem, 1.5vw, 0.9rem);
-  color: var(--pico-muted-color, #888880);
-  font-style: italic;
-}
-
 .highlighted-placeholder {
   font-size: 0.9rem;
   color: var(--pico-muted-color, #888880);

src/routes/+page.svelte

@@ -117,7 +117,6 @@
       <span class="highlighted-eq-sep">=</span>
       <span class="highlighted-eq-to">{formatBig(highlightedResult.convertedValue)} {highlightedResult.unit.labelPlural}</span>
     </div>
-    <span class="highlighted-symbol">{highlightedResult.unit.symbol}</span>
   {:else}
     <span class="highlighted-placeholder">Click a result to highlight it</span>
   {/if}