style: distinguish reply nickname color

uniapp/src/pages/my_comments/my_comments.vue

@@ -20,7 +20,9 @@
                 </view>
 
                 <view v-if="item.reply_to" class="comment-card__reply">
-                    <text class="comment-card__reply-user">回复 {{ formatNickname(item.reply_to.user?.nickname || '该用户') }}：</text>
+                    <text class="comment-card__reply-prefix">回复 </text>
+                    <text class="comment-card__reply-name">{{ formatNickname(item.reply_to.user?.nickname || '该用户') }}</text>
+                    <text>：</text>
                     <text class="comment-card__reply-content">{{ item.reply_to.content }}</text>
                 </view>
 
@@ -198,10 +200,15 @@ const formatTime = (value: string | number) => {
     line-height: 36rpx;
 }
 
-.comment-card__reply-user {
+.comment-card__reply-prefix {
     color: #4d78d9;
 }
 
+.comment-card__reply-name {
+    color: #344055;
+    font-weight: 500;
+}
+
 .comment-card__content {
     display: block;
     color: #1f2937;