修改

src/components/sale/quotation-form.vue

 <template>
-  <q-card class="q-px-md" style="width:750px;max-width:800px;">
+  <q-card class="q-px-md" style="width:800px;max-width:800px;">
     <q-card-section class="row items-center q-pb-none">
       <div class="text-h6">{{model.Id==0?"创建报价单":"修改报价单"}}</div>
       <q-space />
@@ -53,8 +53,8 @@
         <span>选择课程</span>
       </div>
       <div class="row">
-        <div class="col">
-          <q-select @input="getCourses" standout v-model="msg.CourseSubject" :options="CourseSubjectList"
+        <div class="col-3">
+          <q-select @input="getCourses" dense standout behavior="menu" class="q-mr-md" filled v-model="msg.CourseSubject" :options="CourseSubjectList"
             option-label="Name" option-value="Id" emit-value map-options label="所属科目" clearable />
         </div>
         <div class="col">
@@ -345,6 +345,7 @@
           IsQPrice: 1,
           CourseSubject: this.msg.CourseSubject,
         };
+        this.chosenCourse = null;
         queryCourseDropdownList(qMsg).then(res => {
           this.courseList = res.Data;
           this.courseOptions = this.courseList;