Fixes for NIRVSS UI spectral plot view (#3310)

- Fixed Plotly axis label title font sizing;
- Fixed Plotly axis vertical line color;
- Removed styling that caused `c-button` within
`h-local-controls--overlay-content` to be background on background
color;

src/styles/_controls.scss

@@ -915,14 +915,6 @@ input[type="range"] {
         display: inline-flex;
         align-items: center;
     }
-
-    &--overlay-content {
-        > .c-button {
-            background: $colorLocalControlOvrBg;
-            border-radius: $controlCr;
-            box-shadow: $colorLocalControlOvrBg 0 0 0 2px;
-        }
-    }
 }
 
 .c-local-controls {

src/styles/plotly.scss

@@ -29,7 +29,8 @@
         stroke-width: 1 !important;
     }
 
-    .cartesianlayer .gridlayer {
+    .cartesianlayer {
+        .gridlayer {
             .x,
             .y {
                 path {
@@ -39,10 +40,15 @@
             }
         }
 
+        path.xy2-y {
+            stroke: $colorPlotHash !important;
+        }
+    }
+
     .xtick,
     .ytick,
-    .g-xtitle,
+    [class^="g-"] text[class*="title"] {
-    .g-ytitle {
+        // Matches <g class="g-*"> <text class="*title">
         text {
             fill: $colorPlotFg !important;
             font-size: 12px !important;