feat(website): 三轮视觉改造与页面过渡动画

改造概要（30项）：
- 第一轮：Hero重构/Section差异化/SocialProof强化/CTA对比度/About架构
- 第二轮：字体优化/背景交替/Solutions差异化/Footer五列/MegaDropdown修复
- 第三轮：卡片交互/表单层级/CTA统一/时间线标记/连接线/三列布局/移动导航/Button微交互/SEO Schema
- P3-2：template.tsx+Framer Motion页面过渡/loading.tsx加载状态
- 清理：删除未用组件/hooks，修复重复移动导航，清理冗余CSS

src/app/(marketing)/template.tsx

@@ -0,0 +1,50 @@
+'use client';
+
+import { motion, type Variants } from 'framer-motion';
+import { useReducedMotion } from '@/hooks/use-reduced-motion';
+
+const pageVariants: Variants = {
+  initial: {
+    opacity: 0,
+    y: 8,
+  },
+  enter: {
+    opacity: 1,
+    y: 0,
+    transition: {
+      duration: 0.35,
+      ease: [0.16, 1, 0.3, 1] as [number, number, number, number],
+    },
+  },
+  exit: {
+    opacity: 0,
+    y: -4,
+    transition: {
+      duration: 0.2,
+      ease: [0.16, 1, 0.3, 1] as [number, number, number, number],
+    },
+  },
+};
+
+export default function MarketingTemplate({
+  children,
+}: {
+  children: React.ReactNode;
+}) {
+  const shouldReduceMotion = useReducedMotion();
+
+  if (shouldReduceMotion) {
+    return <>{children}</>;
+  }
+
+  return (
+    <motion.div
+      initial="initial"
+      animate="enter"
+      exit="exit"
+      variants={pageVariants}
+    >
+      {children}
+    </motion.div>
+  );
+}