ui: 删除 /companies Hero 的中字 logo 占位框及边框

Co-Authored-By: Claude <noreply@anthropic.com>

offer_frontend/src/views/portal/CompanyListView.vue

@@ -4,10 +4,6 @@
     <!-- ① 总院 Hero -->
     <section class="hero-section">
       <div class="hero-inner">
-        <div class="hero-logo">
-          <img v-if="group.logo" :src="group.logo" alt="logo" />
-          <div v-else class="logo-placeholder">{{ group.name?.charAt(0) }}</div>
-        </div>
         <div class="hero-content">
           <h1 class="hero-name hero-name-link" @click="$router.push(`/companies/${group.id}`)">{{ group.name }}</h1>
           <div class="hero-meta">
@@ -174,27 +170,6 @@ onMounted(async () => {
   gap: 36px;
   align-items: flex-start;
 }
-.hero-logo {
-  flex-shrink: 0;
-  width: 96px;
-  height: 96px;
-  border-radius: 4px;
-  overflow: hidden;
-  border: 1px solid var(--border);
-  background: var(--bg-page);
-}
-.hero-logo img { width: 100%; height: 100%; object-fit: cover; }
-.logo-placeholder {
-  width: 100%;
-  height: 100%;
-  display: flex;
-  align-items: center;
-  justify-content: center;
-  font-family: var(--serif);
-  font-size: 36px;
-  font-weight: 700;
-  color: var(--brand-red);
-}
 .hero-name {
   font-family: var(--serif);
   font-size: 28px;