Fix hardcoded release icons

internal/assets/static/main.css

@@ -709,6 +709,7 @@ kbd:active {
     width: 16px;
     height: 16px;
     flex-shrink: 0;
+    opacity: 0.4;
 }
 
 .market-chart {
@@ -887,6 +888,7 @@ kbd:active {
     background-color: var(--color-widget-background-highlight);
     border-radius: var(--border-radius);
     padding: 0.5rem;
+    opacity: 0.7;
 }
 
 .bookmarks-icon {
@@ -895,10 +897,6 @@ kbd:active {
     opacity: 0.8;
 }
 
-.simple-icon {
-    opacity: 0.7;
-}
-
 :root:not(.light-scheme) .simple-icon {
     filter: invert(1);
 }
@@ -1073,6 +1071,10 @@ kbd:active {
     transition: filter 0.3s, opacity 0.3s;
 }
 
+.monitor-site-icon.simple-icon {
+    opacity: 0.7;
+}
+
 .monitor-site:hover .monitor-site-icon {
     filter: grayscale(0);
     opacity: 1;