feat(ui): refine profile workflows and visual system

pages/defaults/index.wxml

@@ -3,12 +3,13 @@
     <view>
       <text class="eyebrow">档案预设</text>
       <view class="page-heading">
-        <text class="heading-icon">＋</text>
-        <text class="page-title">学生档案预设项</text>
+        <text class="page-title">新增学生默认值</text>
       </view>
-      <text class="page-subtitle">用于新增学生时自动带出</text>
+      <text class="page-subtitle">新增学生时自动带出以下信息</text>
     </view>
-    <button class="reload-button secondary-button" loading="{{loading}}" disabled="{{loading}}" bindtap="onReload">↻ 刷新</button>
+    <button class="reload-button {{loading ? 'reload-button-loading' : ''}}" disabled="{{loading || saving}}" bindtap="onReload" aria-label="刷新预设项">
+      <text class="reload-icon">↻</text>
+    </button>
   </view>
 
   <view wx:if="{{errorMessage}}" class="status-banner">
@@ -18,41 +19,70 @@
 
   <view class="defaults-card surface">
     <view class="defaults-grid">
-      <picker class="select-field" mode="selector" range="{{grades}}" bindchange="onGradeChange">
-        <text class="field-label">年级</text>
-        <text class="field-value">{{defaults.grade}}</text>
+      <picker class="select-field" mode="selector" range="{{grades}}" disabled="{{loading || saving}}" bindchange="onGradeChange" aria-label="默认年级，当前为 {{defaults.grade}}">
+        <view class="select-field-content">
+          <view class="select-copy">
+            <text class="field-label">年级</text>
+            <text class="field-value">{{defaults.grade}}</text>
+          </view>
+          <text class="select-chevron" aria-hidden="true">›</text>
+        </view>
       </picker>
-      <picker class="select-field" mode="selector" range="{{subjects}}" bindchange="onSubjectChange">
-        <text class="field-label">学科</text>
-        <text class="field-value">{{defaults.subject}}</text>
+      <picker class="select-field" mode="selector" range="{{subjects}}" disabled="{{loading || saving}}" bindchange="onSubjectChange" aria-label="默认学科，当前为 {{defaults.subject}}">
+        <view class="select-field-content">
+          <view class="select-copy">
+            <text class="field-label">学科</text>
+            <text class="field-value">{{defaults.subject}}</text>
+          </view>
+          <text class="select-chevron" aria-hidden="true">›</text>
+        </view>
       </picker>
     </view>
 
     <view class="duration-field">
-      <text class="field-label">上课时长</text>
-      <view class="duration-input-row">
-        <input class="duration-input" type="number" value="{{defaults.lessonDurationMinutes}}" bindblur="onDurationInput" />
-        <text class="duration-unit">分钟</text>
+      <view class="duration-heading">
+        <text class="field-label">上课时长</text>
+        <text class="duration-step-label">15 分钟间隔</text>
       </view>
-      <slider
-        class="duration-slider"
-        min="15"
-        max="360"
-        step="15"
-        value="{{defaults.lessonDurationMinutes}}"
-        activeColor="#2B67E8"
-        backgroundColor="#DBE7F5"
-        blockColor="#2B67E8"
-        blockSize="26"
-        bindchange="onDurationChange"
-      />
-      <view class="duration-bounds">
-        <text>15 分钟</text>
-        <text>360 分钟</text>
+
+      <view class="duration-stepper">
+        <button
+          class="duration-step-button"
+          disabled="{{loading || saving || defaults.lessonDurationMinutes <= minimumDuration}}"
+          bindtap="decreaseDuration"
+          aria-label="减少 15 分钟"
+        >−</button>
+        <view class="duration-value" aria-label="当前上课时长 {{defaults.lessonDurationMinutes}} 分钟">
+          <text class="duration-number">{{defaults.lessonDurationMinutes}}</text>
+          <text class="duration-unit">分钟</text>
+        </view>
+        <button
+          class="duration-step-button"
+          disabled="{{loading || saving || defaults.lessonDurationMinutes >= maximumDuration}}"
+          bindtap="increaseDuration"
+          aria-label="增加 15 分钟"
+        >＋</button>
+      </view>
+
+      <view class="duration-presets" aria-label="常用上课时长">
+        <button
+          wx:for="{{durationPresets}}"
+          wx:key="*this"
+          class="duration-preset {{defaults.lessonDurationMinutes === item ? 'duration-preset-active' : ''}}"
+          disabled="{{loading || saving}}"
+          data-value="{{item}}"
+          bindtap="selectDurationPreset"
+          aria-label="设置为 {{item}} 分钟"
+        >{{item}}</button>
       </view>
     </view>
 
-    <view class="time-help">新增学生时会按开始时间自动推算结束时间。</view>
-    <button class="save-defaults primary-button" loading="{{saving}}" disabled="{{saving || loading}}" bindtap="save">保存</button>
+    <view class="time-help">
+      <icon class="time-help-icon" type="info" size="16" color="#6E6E73" />
+      <text>新增学生时会根据开始时间自动推算结束时间</text>
+    </view>
+    <view class="save-area">
+      <button class="save-defaults primary-button" loading="{{saving}}" disabled="{{saving || loading}}" bindtap="save">保存</button>
+    </view>
   </view>
 </view>