revert: Remove mobile rainbow glow adjustments

Reverts #46 and #47. The reduced background-size caused a green
tint at rest. The improvement in animation visibility wasn't
worth the trade-off.

src/compose_farm/web/static/app.css

@@ -70,7 +70,6 @@
 
 #cmd-fab {
     --g: linear-gradient(to right, #fff, #fff, #0ff, #00f, #8000ff, #e066a3, #f00, #ff0, #bfff80, #fff, #fff);
-    --bg-size: 900%;
     all: unset;
     position: fixed;
     bottom: 1.5rem;
@@ -91,7 +90,7 @@
 }
 
 .cmd-fab-inner > span {
-    background: var(--g) no-repeat calc(var(--cmd-pos) * 1%) 0 / var(--bg-size);
+    background: var(--g) no-repeat calc(var(--cmd-pos) * 1%) 0 / 900%;
     -webkit-background-clip: text;
     background-clip: text;
     -webkit-text-fill-color: transparent;
@@ -107,7 +106,7 @@
 
 .cmd-fab-inner::before {
     inset: -1.5px;
-    background: var(--g) no-repeat calc(var(--cmd-pos) * 1%) 0 / var(--bg-size);
+    background: var(--g) no-repeat calc(var(--cmd-pos) * 1%) 0 / 900%;
     border-radius: 9px;
     z-index: -1;
     opacity: var(--cmd-opacity);
@@ -124,8 +123,3 @@
 #cmd-fab:hover { --cmd-scale: 1.05; --cmd-pos: 0; --cmd-blur: 30; --cmd-opacity: 1; }
 #cmd-fab:hover .cmd-fab-inner::after { background: var(--g); opacity: 0.3; }
 #cmd-fab:active { --cmd-scale: 0.98; --cmd-blur: 15; }
-
-/* Smaller screens: reduce gradient size so more colors are visible */
-@media (max-width: 768px) {
-    #cmd-fab { --bg-size: 650%; }
-}