[fix] 修复吸附组件的背景颜色bug

tuniao-ui/components/tn-sticky/tn-sticky.vue

@@ -12,7 +12,8 @@
           top: stickyTop + 'px',
           left: left + 'px',
           width: width === 'auto' ? 'auto' : width + 'px',
-          zIndex: elZIndex
+          zIndex: elZIndex,
+          backgroundColor: backgroundColorStyle
         }"
       >
         <slot></slot>
@@ -83,9 +84,6 @@
       stickyStyle() {
         let style = {}
         style.height = this.fixed ? this.height + 'px' : 'auto'
-        if (this.backgroundColorStyle) {
-          style.color = this.backgroundColorStyle
-        }
         if (this.elZIndex) {
           style.zIndex = this.elZIndex
         }