fix(ui): about hero 下划线不再遮挡副标题 + home hero 移除重复 Logo

- about-content-v4: hero 标题强调下划线 absolute -bottom-2 → bottom-0，
  不再向下溢出侵入下一行文字（浏览器几何验证：下划线 642-645px 位于
  '专业核心团队'(521-629) 与 '的转型伙伴'(656-764) 间隙，零遮挡）
- home-content-v15: hero 删除品牌 Logo（与导航栏重复），slogan badge
  成为首元素；移除 Image import
- 测试：hero logo 断言改为 'hero 内不重复渲染 img（与 header 去重）'
- 视觉基线更新 4 张：home-fullpage / about-fullpage / theme-light-main / theme-dark-main

src/app/(marketing)/about/about-content-v4.tsx

@@ -73,7 +73,7 @@ function HeroSection({ data }: { data: AboutData }) {
                     <span className="relative text-brand font-black">
                       {line}
                       <motion.span
-                        className="absolute -bottom-2 left-0 w-full h-[3px] bg-brand"
+                        className="absolute bottom-0 left-0 w-full h-[3px] bg-brand"
                         style={{ transformOrigin: 'left' }}
                         initial={{ scaleX: 0 }}
                         animate={{ scaleX: 1 }}

src/app/(marketing)/home-content-v15.test.tsx

@@ -89,12 +89,13 @@ jest.mock('lucide-react', () => {
 });
 
 describe('HomeContentV15 - 浅色 Hero（暗黑模式 token 友好）', () => {
-  it('renders the light canvas hero with a brand logo variant', () => {
+  it('does not repeat the brand logo inside the hero (dedup with header)', () => {
     render(<HomeContentV15 />);
 
-    expect(screen.getByTestId('hero-section')).toBeInTheDocument();
-    const heroLogo = screen.getByTestId('mock-next-image');
-    expect(heroLogo).toHaveAttribute('src', '/logo.svg');
+    const hero = screen.getByTestId('hero-section');
+    expect(hero).toBeInTheDocument();
+    // hero 内不应再有 Logo（导航栏已展示，避免重复）；slogan badge 保留
+    expect(hero.querySelector('img')).toBeNull();
   });
 
   it('keeps a single primary CTA and demotes the secondary action to a text link', () => {

src/app/(marketing)/home-content-v15.tsx

@@ -1,7 +1,6 @@
 'use client';
 
 import { useRef } from 'react';
-import Image from 'next/image';
 import { motion } from 'framer-motion';
 import { ScrollReveal, StaggerReveal } from '@/components/ui/scroll-reveal';
 import { Badge } from '@/components/ui/badge';
@@ -172,24 +171,7 @@ function HeroSection({ heroData, stats }: {
       <div className="max-w-container mx-auto px-4 sm:px-6 lg:px-10 relative z-10 w-full py-16 sm:py-20 md:py-24 lg:py-24">
         <div className="grid items-center gap-16 lg:grid-cols-[1.05fr_0.95fr]">
         <div className="max-w-4xl">
-          {/* 品牌标识：浅色画布使用深色版 Logo（深色版见 footer 深色区块） */}
-          <motion.div
-            initial={{ opacity: 0, y: 20 }}
-            animate={{ opacity: 1, y: 0 }}
-            transition={{ duration: 0.35, delay: 0, ease: EASE_OUT }}
-            className="mb-6"
-          >
-            <Image
-              src="/logo.svg"
-              alt={`${COMPANY_INFO.name} Logo`}
-              width={224}
-              height={56}
-              className="h-12 w-auto sm:h-14"
-              priority
-            />
-          </motion.div>
-
-          {/* 品牌口号 Badge：浅色画布上的品牌红信号 */}
+          {/* 品牌口号 Badge：浅色画布上的品牌红信号（hero 不重复渲染 Logo，避免与导航栏重复） */}
           {slogan && (
             <motion.div
               initial={{ opacity: 0, y: 20 }}