```css
/* ============================================
   五一黑塑料网 · 设计系统
   风格概念：熔光塑纸 —— 半透明塑料层叠 + 暖色杂志风
   配色：暖米白 × 朱红 × 青绿 × 芥末黄
   ============================================ */

:root {
  --bg: #F5EFE6;
  --bg-alt: #EEE4D5;
  --surface: rgba(255, 255, 255, 0.55);
  --surface-strong: rgba(255, 255, 255, 0.85);
  --primary: #E85D3C;
  --primary-dark: #D0462A;
  --secondary: #1A7A6A;
  --accent: #E9C46A;
  --text: #262A35;
  --text-muted: rgba(38, 42, 53, 0.68);
  --border: rgba(255, 255, 255, 0.7);
  --shadow-sm: 0 4px 16px rgba(38, 42, 53, 0.06);
  --shadow-md: 0 8px 32px rgba(232, 93, 60, 0.12);
  --shadow-lg: 0 20px 60px rgba(232, 93, 60, 0.16);
  --radius: 16px;
  --radius-lg: 24px;
}

/* 基础重置 */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: system-ui, 'PingFang SC', 'Microsoft YaHei', sans-serif; overflow-x: hidden; color: var(--text); line-height: 1.6; }
body { background: radial-gradient(circle at 12% 22%, rgba(232, 93, 60, 0.05) 0%, transparent 38%), radial-gradient(circle at 88% 78%, rgba(26, 122, 106, 0.05) 0%, transparent 42%), var(--bg); }

/* 核心布局 — 居中 */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: 90px 0; position: relative; }
.section:nth-child(even) { background: var(--bg-alt); }

/* ============================
   导航 — 固定顶部
   ============================ */
.site-header { position: fixed; top: 0; left: 0; width: 100%; z-index: 1000; background: rgba(245, 239, 230, 0.75); backdrop-filter: blur(24px); -webkit-backdrop-filter: blur(24px); border-bottom: 1px solid rgba(255, 255, 255, 0.6); box-shadow: 0 1px 20px rgba(38, 42, 53, 0.04); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.logo { display: flex; align-items: center; gap: 12px; font-weight: 800; font-size: 1.25rem; text-decoration: none; color: var(--text); letter-spacing: 0.5px; transition: opacity 0.25s; }
.logo:hover { opacity: 0.8; }
.logo-icon { width: 38px; height: 38px; border-radius: 12px; display: flex; align-items: center; justify-content: center; font-size: 1rem; font-weight: 800; font-style: normal; background: linear-gradient(135deg, #E85D3C 0%, #E9C46A 100%); color: #fff; box-shadow: 0 4px 14px rgba(232, 93, 60, 0.3); letter-spacing: 0; }
.main-nav { display: flex; align-items: center; gap: 28px; list-style: none; }
.main-nav a { text-decoration: none; font-size: 0.9rem; font-weight: 500; color: var(--text); position: relative; transition: color 0.25s; }
.main-nav a:not(.nav-cta)::after { content: ''; position: absolute; bottom: -6px; left: 0; width: 0; height: 2px; background: var(--primary); border-radius: 2px; transition: width 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94); }
.main-nav a:not(.nav-cta):hover { color: var(--primary); }
.main-nav a:not(.nav-cta):hover::after { width: 100%; }
.nav-cta { padding: 10px 22px; border-radius: 50px; color: #fff !important; font-weight: 600; background: linear-gradient(135deg, var(--primary), var(--primary-dark)); box-shadow: 0 4px 16px rgba(232, 93, 60, 0.3); transition: all 0.3s; }
.nav-cta:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(232, 93, 60, 0.4); }
.menu-toggle { display: none; align-items: center; justify-content: center; width: 40px; height: 40px; border: none; background: transparent; cursor: pointer; border-radius: 10px; font-size: 1.5rem; color: var(--text); transition: background 0.2s; }
.menu-toggle:hover { background: rgba(232, 93, 60, 0.08); }

/* ============================
   首页 Hero
   ============================ */
.hero { min-height: 75vh; display: flex; align-items: center; justify-content: space-between; gap: 60px; position: relative; overflow: hidden; padding: 140px 0 80px; }
.hero::before { content: '51'; position: absolute; right: -30px; bottom: -50px; font-size: 22rem; font-weight: 900; line-height: 1; color: rgba(232, 93, 60, 0.06); pointer-events: none; z-index: 0; letter-spacing: -0.04em; user-select: none; }
.hero::after { content: ''; position: absolute; width: 340px; height: 340px; border-radius: 50%; background: linear-gradient(135deg, rgba(26, 122, 106, 0.1), rgba(233, 196, 74, 0.08)); top: -80px; right: 25%; filter: blur(60px); z-index: 0; pointer-events: none; }
.hero-content { max-width: 720px; flex: 1; position: relative; z-index: 1; }
.hero-eyebrow { display: inline-block; font-size: 0.82rem; font-weight: 700; padding: 6px 16px; border-radius: 30px; margin-bottom: 20px; color: var(--primary); background: rgba(232, 93, 60, 0.1); border: 1px solid rgba(232, 93, 60, 0.15); letter-spacing: 1px; text-transform: uppercase; }
.hero h1 { font-size: clamp(2.4rem, 4.5vw, 3.6rem); line-height: 1.18; margin-bottom: 20px; font-weight: 800; letter-spacing: -0.02em; color: var(--text); }
.hero h1 .text-accent { color: var(--primary); }
.hero p { font-size: 1.12rem; opacity: 0.68; max-width: 540px; margin-bottom: 34px; line-height: 1.75; }
.hero-buttons { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-image { flex: 0 0 420px; border-radius: var(--radius-lg); overflow: hidden; background: linear-gradient(135deg, rgba(255, 255, 255, 0.65), rgba(255, 255, 255, 0.3)); backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px); border: 1px solid rgba(255, 255, 255, 0.8); box-shadow: var(--shadow-lg); transform: rotate(2.5deg); position: relative; z-index: 1; transition: transform 0.4s ease; }
.hero-image:hover { transform: rotate(0deg) scale(1.01); }
.hero-image::before { content: ''; position: absolute; top: -25%; left: -25%; width: 70%; height: 70%; background: radial-gradient(circle, rgba(255, 255, 255, 0.5), transparent); pointer-events: none; z-index: 1; }
.hero-image::after { content: ''; position: absolute; bottom: -30%; right: -30%; width: 60%; height: 60%; background: radial-gradient(circle, rgba(233, 196, 74, 0.2), transparent 70%); pointer-events: none; z-index: 1; }
.hero-image img { width: 100%; height: auto; display: block; position: relative; z-index: 0; border-radius: inherit; }

/* ============================
   按钮
   ============================ */
.btn { display: inline-flex; align-items: center; gap: 10px; padding: 14px 32px; border-radius: 50px; font-weight: 600; font-size: 0.95rem; cursor: pointer; border: none; text-decoration: none; transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94); }
.btn-primary { background: linear-gradient(135deg, var(--primary), var(--primary-dark)); color: #fff; box-shadow: 0 6px 22px rgba(232, 93, 60, 0.35); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 32px rgba(232, 93, 60, 0.45); }
.btn-outline { background: transparent; border: 1.5px solid var(--primary); color: var(--primary); }
.btn-outline:hover { background: rgba(232, 93, 60, 0.08); transform: translateY(-2px); }

/* ============================
   标签 / 标题
   ============================ */
.section-label { display: inline-block; font-size: 0.78rem; font-weight: 700; letter-spacing: 2px; margin-bottom: 14px; color: var(--primary); background: rgba(232, 93, 60, 0.1); padding: 6px 16px; border-radius: 30px; text-transform: uppercase; }
.section-title { font-size: clamp(1.8rem, 3vw, 2.4rem); margin-bottom: 14px; font-weight: 800; letter-spacing: -0.02em; color: var(--text); }
.section-desc { max-width: 600px; opacity: 0.68; margin-bottom: 48px; font-size: 1.02rem; line-height: 1.7; }

/* ============================
   卡片网格
   ============================ */
.cards-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 26px; }
.category-card { border-radius: var(--radius); padding: 32px; border: 1px solid rgba(255, 255, 255, 0.7); background: var(--surface); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); transition: all 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94); position: relative; overflow: hidden; }
.category-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 42%; background: linear-gradient(to bottom, rgba(255, 255, 255, 0.28), transparent); pointer-events: none; border-radius: inherit; }
.category-card::after { content: ''; position: absolute; bottom: -30px; right: -30px; width: 90px; height: 90px; background: linear-gradient(135deg, transparent 50%, rgba(232, 93, 60, 0.06) 50%); border-radius: 50%; pointer-events: none; transition: transform 0.4s; }
.category-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); border-color: rgba(232, 93, 60, 0.18); }
.category-card:hover::after { transform: scale(1.4); }
.card-icon { width: 52px; height: 52px; border-radius: 14px; display: flex; align-items: center; justify-content: center; margin-bottom: 18px; font-size: 1.4rem; position: relative; z-index: 1; background: rgba(232, 93, 60, 0.12); color: var(--primary); box-shadow: 0 2px 8px rgba(232, 93, 60, 0.1); transition: transform 0.3s; }
.category-card:hover .card-icon { transform: scale(1.08) rotate(-5deg); }
.category-card:nth-child(3n+2) .card-icon { background: rgba(26, 122, 106, 0.12); color: var(--secondary); box-shadow: 0 2px 8px rgba(26, 122, 106, 0.1); }
.category-card:nth-child(3n+3) .card-icon { background: rgba(233, 196, 74, 0.2); color: #C99A2E; box-shadow: 0 2px 8px rgba(233, 196, 74, 0.15); }
.card-link { font-weight: 700; font-size: 0.85rem; text-decoration: none; color: var(--primary); display: inline-flex; align-items: center; gap: 6px; position: relative; z-index: 1; transition: gap 0.25s; }
.card-link:hover { gap: 12px; }

/* ============================
   特性块
   ============================ */
.feature-block { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.feature-image { border-radius: var(--radius-lg); overflow: hidden; background: linear-gradient(135deg, rgba(26, 122, 106, 0.08), rgba(232, 93, 60, 0.06)); padding: 24px; position: relative; border: 1px solid rgba(255, 255, 255, 0.65); }
.feature-image::before { content: ''; position: absolute; top: -20%; right: -20%; width: 50%; height: 50%; background: radial-gradient(circle, rgba(255, 255, 255, 0.4), transparent); pointer-events: none; z-index: 1; }
.feature-image img { width: 100%; height: auto; display: block; border-radius: 14px; border: 1px solid rgba(255, 255, 255, 0.8); box-shadow: 0 12px 34px rgba(38, 42, 53, 0.1); position: relative; z-index: 0; }
.feature-text { position: relative; }
.feature-text .section-title { font-size: 1.9rem; margin-bottom: 18px; }
.feature-list { list-style: none; margin-top: 24px; }
.feature-list li { padding: 8px 0; display: flex; align-items: center; gap: 12px; font-size: 1rem; color: var(--text); }
.feature-list li::before { content: '✓'; font-weight: 800; color: var(--primary); background: rgba(232, 93, 60, 0.1); width: 24px; height: 24px; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; font-size: 0.75rem; flex-shrink: 0; }

/* ============================
   数据条
   ============================ */
.stats-bar { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; text-align: center; }
.stat-item { padding: 32px 20px; border-radius: var(--radius-lg); border: 1px solid rgba(255, 255, 255, 0.7); background: var(--surface); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); position: relative; overflow: hidden; transition: all 0.3s; }
.stat-item::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 40%; background: linear-gradient(to bottom, rgba(255, 255, 255, 0.2), transparent); pointer-events: none; }
.stat-item:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: rgba(232, 93, 60, 0.15); }
.stat-number { font-size: 2.8rem; font-weight: 800; color: var(--primary); line-height: 1.1; letter-spacing: -0.03em; }
.stat-item:nth-child(2) .stat-number { color: var(--secondary); }
.stat-item:nth-child(3) .stat-number { color: #C99A2E; }
.stat-item:nth-child(4) .stat-number { color: var(--primary-dark); }
.stat-label { font-size: 0.9rem; opacity: 0.62; margin-top: 8px; font-weight: 500; letter-spacing: 0.5px; }

/* ============================
   内容墙
   ============================ */
.content-wall { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 26px; }
.content-wall-item { border-radius: var(--radius); overflow: hidden; border: 1px solid rgba(255, 255, 255, 0.7); background: var(--surface); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); transition: all 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94); position: relative; }
.content-wall-item::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 100%; background: linear-gradient(to bottom, rgba(255, 255, 255, 0.12), transparent 38%); pointer-events: none; z-index: 1; }
.content-wall-item:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); border-color: rgba(232, 93, 60, 0.16); }
.content-wall-item img { width: 100%; height: 200px; object-fit: cover; display: block; transition: transform 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94); }
.content-wall-item:hover img { transform: scale(1.06); }
.content-wall-body { padding: 22px; position: relative; z-index: 2; }
.content-wall-body h3 { font-size: 1.05rem; font-weight: 700; margin-bottom: 8px; color: var(--text); }
.content-wall-body p { font-size: 0.88rem; opacity: 0.66; line-height: 1.6; }

/* ============================
   FAQ
   ============================ */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { border: 1px solid rgba(255, 255, 255, 0.7); border-radius: var(--radius); margin-bottom: 10px; overflow: hidden; cursor: pointer; background: var(--surface); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); transition: all 0.3s; position: relative; }
.faq-item::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 35%; background: linear-gradient(to bottom, rgba(255, 255, 255, 0.2), transparent); pointer-events: none; }
.faq-item:hover { border-color: rgba(232, 93, 60, 0.15); }
.faq-item.open { background: var(--surface-strong); box-shadow: var(--shadow-sm); border-color: rgba(232, 93, 60, 0.12); }
.faq-item .faq-question { padding: 18px 24px; font-weight: 600; font-size: 1rem; display: flex; justify-content: space-between; align-items: center; color: var(--text); position: relative; z-index: 1; transition: color 0.2s; }
.faq-item .faq-question::after { content: '+'; font-size: 1.5rem; font-weight: 300; color: var(--primary); transition: transform 0.35s ease; line-height: 1; }
.faq-item.open .faq-question::after { content: '−'; transform: rotate(180deg); }
.faq-item .faq-answer { padding: 0 24px 20px; display: none; opacity: 0.72; line-height: 1.75; font-size: 0.95rem; position: relative; z-index: 1; }
.faq-item.open .faq-answer { display: block; animation: fadeIn 0.3s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(-6px); } to { opacity: 0.72; transform: translateY(0); } }

/* ============================
   CTA 横幅
   ============================ */
.cta-banner { padding: 64px 32px; text-align: center; border-radius: var(--radius-lg); background: linear-gradient(135deg, #E85D3C 0%, #D0462A 60%, #C9351F 100%); color: #fff; position: relative; overflow: hidden; box-shadow: 0 20px 50px rgba(232, 93, 60, 0.3); }
.cta-banner::before { content: ''; position: absolute; width: 280px; height: 280px; background: rgba(255, 255, 255, 0.08); border-radius: 50%; top: -90px; right: -40px; }
.cta-banner::after { content: ''; position: absolute; width: 160px; height: 160px; background: rgba(233, 196, 74, 0.25); border-radius: 50%; bottom: -50px; left: 30px; }
.cta-banner h2 { color: #fff; font-size: clamp(1.7rem, 3vw, 2.3rem); font-weight: 800; margin-bottom: 12px; position: relative; z-index: 1; letter-spacing: -0.02em; }
.cta-banner p { color: rgba(255, 255, 255, 0.85); position: relative; z-index: 1; max-width: 500px; margin: 0 auto 32px; font-size: 1.05rem; line-height: 1.65; }
.cta-banner .btn { position: relative; z-index: 1; }
.cta-banner .btn-primary { background: #fff; color: var(--primary); box-shadow: 0 8px 26px rgba(0, 0, 0, 0.15); }
.cta-banner .btn-primary:hover { background: rgba(255, 255, 255, 0.92); transform: translateY(-3px); box-shadow: 0 12px 34px rgba(0, 0, 0, 0.2); }

/* ============================
   页脚
   ============================ */
.site-footer { padding: 64px 0 28px; background: var(--bg-alt); border-top: 2px solid rgba(255, 255, 255, 0.6); }
.site-footer .container { position: relative; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 48px; position: relative; }
.footer-brand .logo { margin-bottom: 16px; }
.footer-brand p { color: var(--text-muted); line-height: 1.7; font-size: 0.92rem; max-width: 280px; }
.footer-col h4 { font-size: 0.82rem; font-weight: 700; letter-spacing: 2px; margin-bottom: 18px; color: var(--text); text-transform: uppercase; }
.footer-col a { display: block; color: var(--text-muted); text-decoration: none; font-size: 0.9rem; padding: 5px 0; transition: 0.2s; }
.footer-col a:hover { color: var(--primary); padding-left: 4px; }
.footer-bottom { border-top: 1px solid rgba(38, 42, 53, 0.08); margin-top: 44px; padding-top: 22px; text-align: center; font-size: 0.85rem; color: var(--text-muted); }

/* ============================
   工具类
   ============================ */
.text-accent { color: var(--primary); }
.text-center { text-align: center; }
.seo-description { max-width: 600px; margin: 0 auto 48px; opacity: 0.68; line-height: 1.75; font-size: 1.02rem; }
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

/* ============================
   响应式
   ============================ */
@media (max-width: 992px) {
  .hero { gap: 40px; }
  .hero-image { flex: 0 0 340px; }
  .stats-bar { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .hero { flex-direction: column; padding: 120px 0 60px; text-align: center; }
  .hero-content { max-width: 100%; }
  .hero p { margin-left: auto; margin-right: auto; }
  .hero-buttons { justify-content: center; }
  .hero-image { flex: 0 0 auto; width: 100%; max-width: 420px; transform: rotate(1deg); }
  .hero::before { font-size: 14rem; right: -10px; bottom: -20px; }
  .feature-block { grid-template-columns: 1fr; gap: 40px; }
  .feature-text { text-align: center; }
  .feature-list { text-align: left; max-width: 360px; margin-left: auto; margin-right: auto; }
  .stats-bar { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 36px; }
  .main-nav { display: none; }
  .menu-toggle { display: flex; }
  .main-nav.open { display: flex; flex-direction: column; position: absolute; top: 72px; left: 0; width: 100%; background: rgba(245, 239, 230, 0.98); backdrop-filter: blur(24px); padding: 24px 24px; gap: 18px; border-bottom: 1px solid rgba(255, 255, 255, 0.6); box-shadow: 0 20px 40px rgba(38, 42, 53, 0.08); }
  .main-nav.open a { font-size: 1.05rem; }
  .main-nav.open .nav-cta { display: inline-block; text-align: center; }
  .section { padding: 64px 0; }
}

@media (max-width: 480px) {
  .cards-grid, .content-wall, .stats-bar { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-buttons { flex-direction: column; width: 100%; }
  .hero-buttons .btn { width: 100%; justify-content: center; }
  .section { padding: 48px 0; }
  .hero h1 { font-size: 2rem; }
  .stat-number { font-size: 2.2rem; }
  .cta-banner { padding: 48px 20px; }
  .footer-grid { gap: 28px; }
}