:root {
  --paper: #FDF6EC;
  --paper-2: #F3EBDD;
  --white: #FFFFFF;
  --ink: #202124;
  --grey: #5B5A5E;
  --line: #D9CBB7;
  --coral: #FF6565;
  --yellow: #FFC93C;
  --teal: #2EC4B6;
  --blue: #3E6EF2;
  --lime: #D3F04E;
}

/* ============ 基础重置 ============ */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: system-ui, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  overflow-x: hidden;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.7;
  position: relative;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 99999;
  pointer-events: none;
  opacity: 0.08;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
}

/* ============ 核心布局 ============ */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 80px 0;
  position: relative;
}

.section:nth-child(even) {
  background: var(--paper-2);
}

/* ============ 导航 ============ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(253, 246, 236, 0.92);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 3px solid var(--ink);
  box-shadow: 0 4px 0 rgba(32, 33, 36, 0.08);
}

.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: 900;
  font-size: 1.35rem;
  text-decoration: none;
  color: var(--ink);
  letter-spacing: -0.02em;
}

.logo-icon {
  width: 42px;
  height: 42px;
  border-radius: 40% 12% 40% 12%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--coral);
  border: 2px solid var(--ink);
  box-shadow: 3px 3px 0 var(--ink);
  font-size: 1.2rem;
  font-weight: 900;
  color: #fff;
  transform: rotate(-6deg);
  transition: transform 0.3s ease;
}

.logo:hover .logo-icon {
  transform: rotate(6deg) scale(1.05);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.main-nav a {
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--ink);
  padding: 6px 0;
  position: relative;
  transition: color 0.2s;
}

.main-nav a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 4px;
  background: var(--coral);
  border-radius: 999px;
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.25s ease;
}

.main-nav a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.main-nav a:hover {
  color: var(--coral);
}

.nav-cta {
  padding: 10px 24px;
  border-radius: 14px;
  background: var(--ink);
  color: #fff !important;
  font-weight: 800;
  border: 2px solid var(--ink);
  box-shadow: 3px 3px 0 var(--coral);
  transition: all 0.2s ease;
}

.nav-cta:hover {
  background: var(--coral);
  border-color: var(--coral);
  box-shadow: 3px 3px 0 var(--ink);
  color: #fff !important;
}

.nav-cta::after {
  display: none;
}

.menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: var(--white);
  border: 2px solid var(--ink);
  box-shadow: 2px 2px 0 var(--ink);
  cursor: pointer;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}

.menu-toggle::before {
  content: '☰';
}

/* ============ Hero ============ */
.hero {
  min-height: 70vh;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
  padding: 140px 0 90px;
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 8% 18%, rgba(255, 201, 60, 0.28) 0%, transparent 32%),
    radial-gradient(circle at 88% 14%, rgba(46, 196, 182, 0.22) 0%, transparent 28%),
    radial-gradient(circle at 72% 88%, rgba(255, 101, 101, 0.16) 0%, transparent 30%),
    linear-gradient(180deg, #FEFAF2 0%, var(--paper) 100%);
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    45deg,
    transparent 0,
    transparent 22px,
    rgba(216, 203, 183, 0.22) 22px,
    rgba(216, 203, 183, 0.22) 23px
  );
  opacity: 0.4;
}

.hero-content {
  max-width: 720px;
  position: relative;
  z-index: 2;
}

.hero-eyebrow {
  display: inline-block;
  font-size: 0.82rem;
  font-weight: 900;
  letter-spacing: 0.12em;
  padding: 6px 18px;
  border-radius: 999px;
  background: var(--white);
  border: 2px solid var(--ink);
  box-shadow: 3px 3px 0 var(--ink);
  color: var(--ink);
  margin-bottom: 20px;
  text-transform: uppercase;
  transform: rotate(-2deg);
}

.hero h1 {
  font-size: clamp(2.4rem, 5.5vw, 4rem);
  line-height: 1.15;
  font-weight: 900;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
  text-shadow: 5px 5px 0 rgba(255, 101, 101, 0.2);
}

.hero h1::after {
  content: '弹幕无涯';
  display: inline-block;
  margin-left: 14px;
  padding: 2px 16px;
  font-size: 0.32em;
  vertical-align: middle;
  background: var(--coral);
  color: #fff;
  border-radius: 999px;
  transform: rotate(4deg);
  border: 2px solid var(--ink);
  box-shadow: 2px 2px 0 var(--ink);
  letter-spacing: 0.04em;
}

.hero p {
  font-size: 1.1rem;
  opacity: 0.8;
  max-width: 560px;
  margin-bottom: 34px;
  font-weight: 500;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-image {
  position: relative;
  border-radius: 32px 10px 32px 10px;
  overflow: hidden;
  border: 3px solid var(--ink);
  box-shadow: 8px 8px 0 var(--yellow);
  background: linear-gradient(145deg, #FFE1A1, #FFC93C);
  min-height: 320px;
  transform: rotate(1.5deg);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.hero-image:hover {
  transform: rotate(0deg) translateY(-4px);
  box-shadow: 10px 10px 0 var(--coral);
}

.hero-image img {
  width: 100%;
  height: 100%;
  min-height: 320px;
  object-fit: cover;
}

.hero-image::before {
  content: '';
  position: absolute;
  right: 18px;
  top: 18px;
  width: 110px;
  height: 110px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.7);
  border: 2px dashed var(--ink);
  z-index: 3;
  pointer-events: none;
}

.hero-image::after {
  content: '▶ 弹幕派对';
  position: absolute;
  left: -12px;
  bottom: 24px;
  padding: 10px 20px;
  background: var(--paper);
  border: 2px solid var(--ink);
  border-radius: 16px 4px 16px 4px;
  box-shadow: 4px 4px 0 var(--ink);
  font-weight: 800;
  font-size: 0.85rem;
  transform: rotate(-5deg);
  z-index: 3;
}

/* ============ 按钮 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 32px;
  border-radius: 14px;
  font-weight: 800;
  font-size: 0.95rem;
  cursor: pointer;
  border: 2px solid var(--ink);
  text-decoration: none;
  transition: all 0.2s ease;
  position: relative;
}

.btn-primary {
  background: var(--coral);
  color: #fff;
  box-shadow: 4px 4px 0 var(--ink);
}

.btn-primary:hover {
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 var(--ink);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--ink);
  color: var(--ink);
  box-shadow: 4px 4px 0 var(--ink);
}

.btn-outline:hover {
  background: var(--yellow);
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 var(--ink);
}

/* ============ 区块标题 ============ */
.section-label {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.14em;
  margin-bottom: 12px;
  padding: 4px 14px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  text-transform: uppercase;
}

.section-title {
  font-size: clamp(1.8rem, 3.5vw, 2.4rem);
  font-weight: 900;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
  text-shadow: 3px 3px 0 rgba(255, 201, 60, 0.55);
}

.section-desc {
  max-width: 600px;
  margin-bottom: 44px;
  color: var(--grey);
  font-size: 1rem;
}

/* ============ 卡片网格 ============ */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 28px;
}

.category-card {
  border-radius: 20px 8px 20px 8px;
  padding: 32px 26px;
  border: 2px solid var(--ink);
  transition: all 0.25s ease;
  position: relative;
  background: var(--white);
  box-shadow: 5px 5px 0 var(--ink);
  overflow: hidden;
}

.category-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 10px;
  background: var(--yellow);
  border-bottom: 2px solid var(--ink);
}

.category-card:nth-child(1)::before { background: var(--yellow); }
.category-card:nth-child(2)::before { background: var(--blue); }
.category-card:nth-child(3)::before { background: var(--coral); }
.category-card:nth-child(4)::before { background: var(--teal); }

.category-card:nth-child(2n) {
  transform: translateY(6px);
}

.category-card:hover {
  transform: translateY(-6px) rotate(-0.8deg);
  box-shadow: 8px 8px 0 var(--ink);
}

.card-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px 6px 16px 6px;
  background: var(--paper-2);
  border: 2px solid var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  font-size: 1.5rem;
  box-shadow: 3px 3px 0 var(--ink);
}

.category-card:hover .card-icon {
  background: var(--paper);
  transform: rotate(-8deg);
}

.card-link {
  font-weight: 800;
  font-size: 0.9rem;
  text-decoration: none;
  color: var(--coral);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 12px;
}

.card-link::after {
  content: '→';
  font-size: 1.2rem;
  transition: transform 0.2s;
}

.category-card:hover .card-link::after {
  transform: translateX(5px);
}

/* ============ 特性区块 ============ */
.feature-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.feature-image {
  border-radius: 30px 8px 30px 8px;
  border: 3px solid var(--ink);
  overflow: hidden;
  box-shadow: 10px 10px 0 var(--teal);
  background: linear-gradient(135deg, #8EE8DE, #2EC4B6);
  min-height: 280px;
  position: relative;
}

.feature-image::after {
  content: '◉ 实时互动';
  position: absolute;
  right: 16px;
  top: 16px;
  padding: 8px 18px;
  background: var(--white);
  border: 2px solid var(--ink);
  border-radius: 999px;
  font-weight: 800;
  font-size: 0.8rem;
  transform: rotate(4deg);
}

.feature-image img {
  width: 100%;
  height: 100%;
  min-height: 280px;
  object-fit: cover;
}

.feature-text .section-label {
  background: var(--teal);
  color: var(--ink);
}

.feature-text .section-title {
  font-size: 2rem;
}

.feature-list {
  list-style: none;
  margin-top: 20px;
}

.feature-list li {
  padding: 10px 0;
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  border-bottom: 2px dashed var(--line);
}

.feature-list li::before {
  content: '✓';
  font-weight: 900;
  color: var(--teal);
  background: var(--white);
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 2px solid var(--ink);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  flex-shrink: 0;
}

/* ============ 数据条 ============ */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 28px;
  text-align: center;
}

.stat-item {
  padding: 30px 16px;
  border-radius: 24px 8px 24px 8px;
  border: 2px solid var(--ink);
  background: var(--white);
  box-shadow: 5px 5px 0 var(--ink);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.stat-item:nth-child(2n) {
  transform: translateY(8px);
}

.stat-item:hover {
  transform: translateY(-4px);
  box-shadow: 8px 8px 0 var(--coral);
}

.stat-number {
  font-size: 2.6rem;
  font-weight: 900;
  letter-spacing: -0.03em;
  color: var(--ink);
}

.stat-number::after {
  content: '+';
  color: var(--coral);
  margin-left: 2px;
}

.stat-label {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--grey);
  margin-top: 8px;
  letter-spacing: 0.04em;
}

/* ============ 内容墙 ============ */
.content-wall {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 28px;
}

.content-wall-item {
  border-radius: 22px 6px 22px 6px;
  border: 2px solid var(--ink);
  background: var(--white);
  overflow: hidden;
  box-shadow: 5px 5px 0 var(--ink);
  transition: all 0.25s ease;
}

.content-wall-item:nth-child(2n) {
  transform: rotate(1.2deg);
}

.content-wall-item:nth-child(3n) {
  transform: rotate(-1deg) translateY(6px);
}

.content-wall-item:hover {
  transform: rotate(0deg) translateY(-6px);
  box-shadow: 8px 8px 0 var(--yellow);
}

.content-wall-item img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-bottom: 2px solid var(--ink);
}

.content-wall-body {
  padding: 22px;
}

.content-wall-body h3 {
  font-size: 1.05rem;
  font-weight: 800;
  margin-bottom: 6px;
}

.content-wall-body p {
  font-size: 0.88rem;
  color: var(--grey);
}

/* ============ FAQ ============ */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
}

.faq-item {
  border: 2px solid var(--ink);
  border-radius: 18px 6px 18px 6px;
  margin-bottom: 14px;
  background: var(--white);
  box-shadow: 4px 4px 0 var(--ink);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
  overflow: hidden;
}

.faq-item:hover {
  transform: translateY(-3px);
  box-shadow: 6px 6px 0 var(--yellow);
}

.faq-item .faq-question {
  padding: 20px 24px;
  font-weight: 800;
  font-size: 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  transition: background 0.2s;
}

.faq-item .faq-question::after {
  content: '+';
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--coral);
  line-height: 1;
  transition: transform 0.2s;
}

.faq-item.open .faq-question::after {
  transform: rotate(45deg);
}

.faq-item.open .faq-question {
  background: var(--paper);
  border-bottom: 2px dashed var(--line);
}

.faq-item .faq-answer {
  padding: 0 24px 20px;
  display: none;
  color: var(--grey);
  line-height: 1.8;
  background: var(--paper);
}

.faq-item.open .faq-answer {
  display: block;
  padding-top: 12px;
}

/* ============ CTA横幅 ============ */
.cta-banner {
  padding: 64px 56px;
  text-align: center;
  border-radius: 32px 10px 32px 10px;
  background: linear-gradient(135deg, var(--teal) 0%, #249D9B 60%, #0F7A8C 100%);
  color: #fff;
  border: 3px solid var(--ink);
  box-shadow: 10px 10px 0 var(--ink);
  position: relative;
  overflow: hidden;
}

.cta-banner::before {
  content: '';
  position: absolute;
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: var(--yellow);
  right: -60px;
  bottom: -70px;
  border: 3px solid var(--ink);
  opacity: 0.85;
}

.cta-banner::after {
  content: '↗';
  position: absolute;
  left: 40px;
  top: 30px;
  font-size: 4rem;
  color: rgba(255, 255, 255, 0.2);
  font-weight: 900;
}

.cta-banner h2 {
  font-size: clamp(1.8rem, 4vw, 2.4rem);
  font-weight: 900;
  color: #fff;
  margin-bottom: 14px;
  position: relative;
  z-index: 2;
  text-shadow: 3px 3px 0 rgba(0, 0, 0, 0.2);
}

.cta-banner p {
  color: rgba(255, 255, 255, 0.9);
  max-width: 520px;
  margin: 0 auto 30px;
  position: relative;
  z-index: 2;
}

.cta-banner .btn-primary {
  background: var(--ink);
  border-color: var(--ink);
  color: #fff;
  box-shadow: 4px 4px 0 var(--yellow);
  position: relative;
  z-index: 2;
}

.cta-banner .btn-primary:hover {
  box-shadow: 6px 6px 0 var(--yellow);
  background: var(--coral);
}

/* ============ 页脚 ============ */
.site-footer {
  padding: 72px 0 28px;
  border-top: 3px solid var(--ink);
  background: var(--paper);
  position: relative;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: -3px;
  left: 0;
  width: 160px;
  height: 10px;
  background: var(--coral);
  border-right: 2px solid var(--ink);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
}

.footer-brand {
  padding-right: 30px;
}

.footer-brand .logo {
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.footer-brand p {
  color: var(--grey);
  font-size: 0.9rem;
  max-width: 260px;
}

.footer-col h4 {
  font-size: 0.95rem;
  font-weight: 800;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.footer-col a {
  display: block;
  color: var(--grey);
  text-decoration: none;
  font-size: 0.9rem;
  padding: 4px 0;
  transition: color 0.2s, transform 0.2s;
}

.footer-col a:hover {
  color: var(--coral);
  transform: translateX(4px);
}

.footer-bottom {
  border-top: 2px dashed var(--line);
  margin-top: 48px;
  padding-top: 22px;
  text-align: center;
  font-size: 0.85rem;
  color: var(--grey);
}

/* ============ 工具类 ============ */
.text-accent {
  color: var(--coral);
  font-weight: 800;
}

.text-center {
  text-align: center;
}

.seo-description {
  max-width: 600px;
  margin: 0 auto 48px;
  text-align: center;
  color: var(--grey);
}

.mt-0 {
  margin-top: 0;
}

.mb-0 {
  margin-bottom: 0;
}

/* ============ 响应式 ============ */
@media (max-width: 768px) {
  .hero {
    grid-template-columns: 1fr;
    gap: 40px;
    padding: 120px 0 60px;
  }

  .hero-content {
    max-width: 100%;
  }

  .hero h1 {
    font-size: 2.3rem;
  }

  .hero h1::after {
    display: block;
    width: fit-content;
    margin: 12px 0 0;
  }

  .hero-image {
    max-width: 100%;
  }

  .feature-block {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }

  .main-nav {
    display: none;
  }

  .menu-toggle {
    display: flex;
  }

  .main-nav.open {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    position: absolute;
    top: 72px;
    left: 12px;
    right: 12px;
    background: var(--paper);
    padding: 24px;
    border-radius: 20px 6px 20px 6px;
    border: 2px solid var(--ink);
    box-shadow: 6px 6px 0 var(--yellow);
    gap: 16px;
    z-index: 999;
  }

  .main-nav.open a {
    width: 100%;
    font-size: 1.1rem;
  }

  .main-nav.open .nav-cta {
    width: 100%;
    text-align: center;
  }

  .cta-banner {
    padding: 48px 28px;
  }

  .site-footer::before {
    width: 80px;
  }
}

@media (max-width: 480px) {
  .cards-grid,
  .content-wall,
  .stats-bar {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .hero-buttons {
    flex-direction: column;
  }

  .hero-buttons .btn {
    width: 100%;
    justify-content: center;
  }

  .section-title {
    font-size: 1.6rem;
  }

  .stat-item:nth-child(2n) {
    transform: none;
  }

  .content-wall-item:nth-child(2n),
  .content-wall-item:nth-child(3n) {
    transform: none;
  }
}