perf: optimize the PostSettingModel component style (halo-dev/console#470)

Signed-off-by: Ryan Wang <i@ryanc.cc>

src/views/post/components/PostSettingModal.vue

@@ -80,12 +80,12 @@
               <a-input-password v-model="form.model.password" autocomplete="new-password" />
             </a-form-item>
             <a-form-item label="封面图：">
-              <div class="post-thumb">
               <a-space direction="vertical">
                 <img
                   :src="form.model.thumbnail || '/images/placeholder.jpg'"
                   alt="Post cover thumbnail"
-                    class="img"
+                  class="w-1/2 cursor-pointer"
+                  style="border-radius: 4px"
                   @click="attachmentSelectVisible = true"
                 />
                 <a-input
@@ -94,7 +94,6 @@
                   placeholder="点击封面图选择图片，或者输入外部链接"
                 ></a-input>
               </a-space>
-              </div>
             </a-form-item>
           </a-form>
         </a-tab-pane>
@@ -125,7 +124,6 @@
     </div>
     <template slot="footer">
       <slot name="extraFooter" />
-      <a-button :disabled="loading" @click="modalVisible = false"> 关闭</a-button>
       <ReactiveButton
         v-if="!form.model.id"
         :errored="form.draftSaveErrored"
@@ -146,6 +144,7 @@
         @callback="handleSavedCallback"
         @click="handleCreateOrUpdate()"
       ></ReactiveButton>
+      <a-button :disabled="loading" @click="modalVisible = false">关闭</a-button>
     </template>
     <AttachmentSelectModal
       :multiSelect="false"