BI-115380 fix: 暗模式下按钮disabled时字体颜色被覆盖

packages/fineui/src/less/base/single/button/button.less

@@ -2,7 +2,7 @@
 @hoverVal: opacity .3s ease;
 @activeVal: transform .5s ease, opacity 1s ease;
 @activeStopVal: transform 0s;
-body .bi-button, #body .bi-button {
+.bi-button {
   &.hack {
     .border-radius(0px);
   }
@@ -479,8 +479,8 @@ body .bi-button, #body .bi-button {
   }
 }
 
-#body .bi-theme-dark {
-  .bi-button, #body .bi-button {
+.bi-theme-dark {
+  .bi-button {
     &.button-ignore {
       background-color: @color-bi-background-ignore-button-theme-dark;
       &:hover, &:focus {