feat(player): 统一移动端主题样式并优化多页面视觉一致性

将玩家端组件与核心页面全面切换为统一主题变量，优化卡片、按钮、弹窗、列表和盘口相关模块的视觉表现，并补充多语言文案以匹配新的交互与布局风格。

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/player/src/components/BackToTopButton.vue

@@ -44,12 +44,12 @@ const { visible, scrollToTop } = useBackToTop(toRef(props, 'scrollEl'));
   width: 44px;
   height: 44px;
   border-radius: 50%;
-  border: 1px solid #E5E7EB;
-  background: #FFFFFF;
-  color: #003D6B;
-  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
+  border: none;
+  background: var(--gradient-primary);
+  color: #FFFFFF;
+  box-shadow: var(--shadow-glow), 0 2px 8px rgba(0, 0, 0, 0.3);
   cursor: pointer;
-  transition: background 0.2s, transform 0.2s;
+  transition: opacity 0.2s, transform 0.2s;
 }
 
 .back-top-btn.above-nav {
@@ -57,7 +57,7 @@ const { visible, scrollToTop } = useBackToTop(toRef(props, 'scrollEl'));
 }
 
 .back-top-btn:active {
-  background: rgba(0, 61, 107, 0.06);
+  opacity: 0.9;
   transform: scale(0.96);
 }