feat: PublicShell + TopNav + 홈 v6 (ai_music_creator 참조)

- 사이드바 대시보드는 /admin, /mypage 에서만 사용
- 공개 페이지는 상단 TopNav + 다크 footer(PublicShell)
- 홈 v6: Hero + Evidence + Before/After + Toolkit + 3-Step + Other Products

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/components/TopNav.tsx

@@ -0,0 +1,152 @@
+'use client';
+
+import Link from 'next/link';
+import { usePathname } from 'next/navigation';
+import { useState, useEffect } from 'react';
+
+const LINKS = [
+  { href: '/', label: 'Home' },
+  { href: '/services/music', label: 'AI 음악' },
+  { href: '/services/blog', label: '블로그 팩' },
+  { href: '/saju', label: 'AI 사주' },
+  { href: '/legal/refund', label: '환불정책' },
+];
+
+export default function TopNav() {
+  const pathname = usePathname();
+  const [open, setOpen] = useState(false);
+  const [scrolled, setScrolled] = useState(false);
+
+  useEffect(() => {
+    const onScroll = () => setScrolled(window.scrollY > 8);
+    onScroll();
+    window.addEventListener('scroll', onScroll, { passive: true });
+    return () => window.removeEventListener('scroll', onScroll);
+  }, []);
+
+  useEffect(() => { setOpen(false); }, [pathname]);
+
+  const isActive = (href: string) =>
+    href === '/' ? pathname === '/' : pathname.startsWith(href);
+
+  return (
+    <>
+      <nav
+        className={`fixed top-0 inset-x-0 z-50 h-20 px-6 lg:px-12 flex items-center justify-between transition-all ${
+          scrolled ? 'backdrop-blur-md' : ''
+        }`}
+        style={{
+          background: scrolled ? 'rgba(6,14,32,0.85)' : 'rgba(6,14,32,0.55)',
+          borderBottom: '1px solid rgba(204,151,255,0.08)',
+          boxShadow: scrolled ? '0 8px 40px 0 rgba(156,72,234,0.12)' : 'none',
+        }}
+      >
+        <Link
+          href="/"
+          className="kx-display text-2xl font-black tracking-tight kx-gradient-text"
+          style={{ textDecoration: 'none' }}
+        >
+          쟁승메이드
+        </Link>
+
+        <div className="hidden md:flex items-center gap-8">
+          {LINKS.map((l) => (
+            <Link
+              key={l.href}
+              href={l.href}
+              className="text-sm font-medium transition-colors"
+              style={{
+                color: isActive(l.href) ? '#fff' : 'var(--kx-on-variant)',
+                borderBottom: isActive(l.href) ? '2px solid var(--kx-primary)' : '2px solid transparent',
+                paddingBottom: 4,
+                textDecoration: 'none',
+              }}
+            >
+              {l.label}
+            </Link>
+          ))}
+        </div>
+
+        <div className="flex items-center gap-3">
+          <Link
+            href="/login"
+            className="hidden sm:inline-block text-sm font-medium px-4 py-2 transition-colors"
+            style={{ color: 'var(--kx-on-variant)', textDecoration: 'none' }}
+          >
+            로그인
+          </Link>
+          <Link
+            href="/services/music"
+            className="kx-btn-primary hidden sm:inline-flex items-center px-5 py-2 rounded-full text-sm"
+            style={{ textDecoration: 'none' }}
+          >
+            시작하기
+          </Link>
+          <button
+            onClick={() => setOpen(true)}
+            aria-label="메뉴 열기"
+            className="md:hidden p-2 rounded-lg"
+            style={{ color: 'var(--kx-on-surface)' }}
+          >
+            <svg className="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 6h16M4 12h16M4 18h16" />
+            </svg>
+          </button>
+        </div>
+      </nav>
+
+      {/* 모바일 오버레이 */}
+      {open && (
+        <div
+          className="fixed inset-0 z-[60] md:hidden flex flex-col"
+          style={{ background: 'rgba(6,14,32,0.98)', backdropFilter: 'blur(16px)' }}
+        >
+          <div className="flex items-center justify-between px-6 h-20">
+            <span className="kx-display text-2xl font-black kx-gradient-text">쟁승메이드</span>
+            <button
+              onClick={() => setOpen(false)}
+              aria-label="메뉴 닫기"
+              className="p-2"
+              style={{ color: 'var(--kx-on-surface)' }}
+            >
+              <svg className="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M6 18L18 6M6 6l12 12" />
+              </svg>
+            </button>
+          </div>
+          <div className="flex-1 flex flex-col gap-2 px-6 pt-6">
+            {LINKS.map((l) => (
+              <Link
+                key={l.href}
+                href={l.href}
+                className="kx-display text-2xl font-bold py-3"
+                style={{
+                  color: isActive(l.href) ? 'var(--kx-primary)' : 'var(--kx-on-surface)',
+                  textDecoration: 'none',
+                }}
+              >
+                {l.label}
+              </Link>
+            ))}
+            <div className="mt-6 flex gap-3">
+              <Link
+                href="/login"
+                className="flex-1 py-3 text-center rounded-full text-sm font-bold"
+                style={{ border: '1px solid rgba(255,255,255,0.15)', color: 'var(--kx-on-surface)', textDecoration: 'none' }}
+              >
+                로그인
+              </Link>
+              <Link
+                href="/services/music"
+                className="kx-btn-primary flex-1 py-3 text-center rounded-full text-sm"
+                style={{ textDecoration: 'none' }}
+              >
+                시작하기
+              </Link>
+            </div>
+          </div>
+        </div>
+      )}
+    </>
+  );
+}