feat: 排行榜虚拟领奖台 + 勋章对齐与尺寸统一

- 领奖台数据不足 3 名时显示虚拟空位(虚线轮廓+虚位以待)
- 领奖台勋章与昵称对齐改为等高盒结构性修复(移除 margin 盲推)
- 全 app 成就勋章图标尺寸统一为 30rpx(前三名/列表/设置页/记录页一致)
- 勋章 SVG 按包围盒精确居中(utils/icons.js)
- 设置页/记录页勋章展示配套调整

pages/timer/timer.js

@@ -56,6 +56,9 @@ Page({
     completionStreak: 0,
     completionLevel: 'normal',
     completionMessage: '',
+    // 完成弹窗科学提示（config.scienceTips 按本次时长选段）
+    completionTipValue: '',
+    completionTipRisk: '',
     icons: iconsMod.build()
   },
 
@@ -700,6 +703,22 @@ Page({
     this._saveAndShowCompletion(elapsed)
   },
 
+  /**
+   * 按本次实际训练时长从 config.scienceTips 选一段提示。
+   * 命中第一条 maxSeconds 大于 elapsed 的配置；缺失配置时返回空（不显示）。
+   */
+  _pickScienceTip(elapsed) {
+    const tips = config.scienceTips || []
+    const sec = Math.max(0, Number(elapsed) || 0)
+    for (const t of tips) {
+      const max = t && t.maxSeconds == null ? Infinity : (t && t.maxSeconds)
+      if (sec < max) {
+        return { value: (t && t.value) || '', risk: (t && t.risk) || '' }
+      }
+    }
+    return { value: '', risk: '' }
+  },
+
   /**
    * Persist the just-finished training and pop the big completion modal.
    * Called from finishTraining (the user manually ends; the timer keeps
@@ -743,6 +762,7 @@ Page({
     try { wx.setStorageSync('_lb_force_refresh', true) } catch (e) {}
 
     const finalStreak = storage.getStreak().count
+    const scienceTip = this._pickScienceTip(elapsed)
 
     this.setData({
       // Background effects keep playing behind the modal
@@ -761,7 +781,10 @@ Page({
       completionOvertime: this.data.isCircuitMode ? 0 : Math.max(0, elapsed - this.data.duration),
       completionStreak: finalStreak,
       completionLevel: level,
-      completionMessage: message
+      completionMessage: message,
+      // 科学提示（按时长分段；无配置时为空字符串，wx:if 不渲染）
+      completionTipValue: scienceTip.value,
+      completionTipRisk: scienceTip.risk
     })
 
     // Animate the big number from 0 to elapsed

pages/timer/timer.wxml

@@ -197,7 +197,6 @@
         <text class="completion-number {{completionElapsed >= 60 ? 'completion-number--long' : ''}}">{{fmt.numPart(completionElapsed)}}</text>
         <text class="completion-unit">{{fmt.unitPart(completionElapsed)}}</text>
       </view>
-      <text class="completion-label">本次训练</text>
 
       <view class="completion-overtime" wx:if="{{completionOvertime > 0}}">
         <text class="overtime-plus">+{{completionOvertime}}</text>
@@ -209,6 +208,15 @@
         <text class="streak-text">连续打卡 {{completionStreak}} 天</text>
       </view>
 
+      <!-- 科学提示：价值行 + 弱化风险行（config.scienceTips 按时长选段） -->
+      <view class="completion-tip" wx:if="{{completionTipValue}}">
+        <text class="completion-tip-value">{{completionTipValue}}</text>
+        <view class="completion-tip-risk" wx:if="{{completionTipRisk}}">
+          <text class="completion-tip-risk-tag">小贴士</text>
+          <text class="completion-tip-risk-text">{{completionTipRisk}}</text>
+        </view>
+      </view>
+
       <view class="completion-actions">
         <view class="completion-btn completion-btn--primary" bindtap="onTrainAgain">
           <text>再来一次</text>

pages/timer/timer.wxss

@@ -474,7 +474,8 @@
   display: flex;
   align-items: baseline;
   justify-content: center;
-  margin-bottom: 8rpx;
+  /* 8rpx 原间距 + 24rpx 原 completion-label 的 margin-bottom，删除标签后合并到这里 */
+  margin-bottom: 32rpx;
 }
 
 .completion-number {
@@ -499,12 +500,6 @@
   margin-left: 8rpx;
 }
 
-.completion-label {
-  font-size: 26rpx;
-  color: var(--text-secondary);
-  margin-bottom: 24rpx;
-}
-
 .completion-overtime {
   display: flex;
   align-items: baseline;
@@ -552,6 +547,54 @@
   font-weight: 500;
 }
 
+.completion-tip {
+  width: 100%;
+  box-sizing: border-box;
+  background: rgba(var(--primary-rgb), 0.08);
+  border-radius: 20rpx;
+  padding: 20rpx 24rpx;
+  margin-bottom: 28rpx;
+  animation: tipIn 0.4s ease 1.0s both;
+}
+
+@keyframes tipIn {
+  0%   { opacity: 0; transform: translateY(12rpx); }
+  100% { opacity: 1; transform: translateY(0); }
+}
+
+.completion-tip-value {
+  display: block;
+  font-size: 26rpx;
+  line-height: 1.5;
+  color: var(--text);
+  font-weight: 500;
+}
+
+.completion-tip-risk {
+  display: flex;
+  align-items: flex-start;
+  gap: 8rpx;
+  margin-top: 10rpx;
+}
+
+.completion-tip-risk-tag {
+  flex-shrink: 0;
+  font-size: 22rpx;
+  line-height: 1.4;
+  color: var(--primary);
+  background: rgba(var(--primary-rgb), 0.14);
+  border-radius: 8rpx;
+  padding: 2rpx 10rpx;
+  margin-top: 2rpx;
+}
+
+.completion-tip-risk-text {
+  flex: 1;
+  font-size: 24rpx;
+  line-height: 1.5;
+  color: var(--text-secondary);
+}
+
 .completion-actions {
   display: flex;
   gap: 20rpx;