feat: make scrollbar opaque.

HMCL/src/main/java/org/jackhuang/hmcl/setting/Theme.java

@@ -87,6 +87,9 @@ public class Theme {
             File temp = File.createTempFile("hmcl", ".css");
             FileUtils.writeText(temp, IOUtils.readFullyAsString(ResourceNotFoundError.getResourceAsStream("/assets/css/custom.css"))
                     .replace("%base-color%", color)
+                    .replace("%base-red%", Integer.toString((int)Math.ceil(paint.getRed() * 256)))
+                    .replace("%base-green%", Integer.toString((int)Math.ceil(paint.getGreen() * 256)))
+                    .replace("%base-blue%", Integer.toString((int)Math.ceil(paint.getBlue() * 256)))
                     .replace("%base-rippler-color%", String.format("rgba(%d, %d, %d, 0.3)", (int) Math.ceil(paint.getRed() * 256), (int) Math.ceil(paint.getGreen() * 256), (int) Math.ceil(paint.getBlue() * 256)))
                     .replace("%disabled-font-color%", String.format("rgba(%d, %d, %d, 0.7)", (int) Math.ceil(textFill.getRed() * 256), (int) Math.ceil(textFill.getGreen() * 256), (int) Math.ceil(textFill.getBlue() * 256)))
                     .replace("%font-color%", getColorDisplayName(getForegroundColor()))

HMCL/src/main/resources/assets/css/custom.css

@@ -19,10 +19,12 @@
     -fx-base-color: %base-color%;
     -fx-base-darker-color: derive(-fx-base-color, -10%);
     -fx-base-check-color: derive(-fx-base-color, 30%);
-    -fx-rippler-color: %base-rippler-color%;
+    -fx-rippler-color: rgba(%base-red%, %base-green%, %base-blue%, 0.3);
     -fx-base-rippler-color: derive(%base-rippler-color%, 100%);
     -fx-base-disabled-text-fill: %disabled-font-color%;
     -fx-base-text-fill: %font-color%;
 
+    -theme-thumb: rgba(%base-red%, %base-green%, %base-blue%, 0.7);
+
     %font%
 }

HMCL/src/main/resources/assets/css/root.css

@@ -23,7 +23,7 @@
 }
 
 .scroll-bar .thumb {
-    -fx-fill: -fx-rippler-color;
+    -fx-fill: -theme-thumb;
     -fx-arc-width: 0;
     -fx-arc-height: 0;
 }