/* ============================================
   A站下载 AcFun流鼻血版官网 — 设计系统
   Style: "Retro Pop Playground"
   Palette: Cream / Coral / Teal / Gold
   ============================================ */

*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --cream: #FDF7EF;
  --cream-deep: #F3E9DC;
  --cream-card: #FFFFFF;
  --coral: #FF5A5F;
  --coral-deep: #E8494E;
  --teal: #00C2A8;
  --teal-deep: #00A08A;
  --gold: #FFC845;
  --gold-deep: #F0B230;
  --ink: #2D2A26;
  --ink-soft: rgba(45, 42, 38, 0.65);
  --ink-faint: rgba(45, 42, 38, 0.35);
  --line: rgba(45, 42, 38, 0.08);
  --shadow-sm: 0 2px 12px rgba(45, 42, 38, 0.04);
  --shadow-md: 0 8px 32px rgba(45, 42, 38, 0.07);
  --shadow-lg: 0 16px 48px rgba(45, 42, 38, 0.09);
  --radius: 20px;
  --radius-sm: 12px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
  font-family: system-ui, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  overflow-x: hidden;
  background: var(--cream);
  color: var(--ink);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

::selection {
  background: var(--coral);
  color: #fff;
}

/* ---------- Container / Section ---------- */

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
}

.section {
  padding: 100px 0;
  position: relative;
}

.section:nth-child(even) {
  background: var(--cream-deep);
}

.section-label {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 3px;
  text-transform: uppercase;
  margin-bottom: 14px;
  color: var(--coral);
  background: rgba(255, 90, 95, 0.08);
  padding: 6px 18px;
  border-radius: 30px;
  border: 1.5px solid rgba(255, 90, 95, 0.2);
  position: relative;
}

.section-label::before {
  content: '✦';
  margin-right: 6px;
  font-size: 0.7rem;
}

.section-title {
  font-size: 2.6rem;
  font-weight: 900;
  letter-spacing: -1px;
  line-height: 1.1;
  margin-bottom: 16px;
  color: var(--ink);
}

.section-title em {
  font-style: normal;
  color: var(--coral);
  position: relative;
  display: inline-block;
}

.section-title em::after {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 0;
  width: 100%;
  height: 6px;
  background: var(--gold);
  border-radius: 4px;
  z-index: -1;
  opacity: 0.5;
}

.section-desc {
  max-width: 600px;
  opacity: 0.7;
  margin-bottom: 48px;
  font-size: 1.02rem;
  line-height: 1.7;
}

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

.text-center .section-desc {
  margin-left: auto;
  margin-right: auto;
}

/* ---------- Header ---------- */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(253, 247, 239, 0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(45, 42, 38, 0.06);
  box-shadow: 0 2px 24px rgba(45, 42, 38, 0.03);
}

.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: 10px;
  font-weight: 900;
  font-size: 1.25rem;
  text-decoration: none;
  color: var(--ink);
  letter-spacing: -0.5px;
}

.logo-icon {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  background: var(--coral);
  color: #fff;
  box-shadow: 0 4px 14px rgba(255, 90, 95, 0.35);
  position: relative;
  overflow: hidden;
}

.logo-icon::after {
  content: '';
  position: absolute;
  top: -6px;
  right: -6px;
  width: 12px;
  height: 12px;
  background: var(--gold);
  border-radius: 50%;
}

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

.main-nav a {
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--ink-soft);
  transition: color 0.25s;
  position: relative;
  padding: 4px 0;
}

.main-nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background: var(--coral);
  border-radius: 2px;
  transition: width 0.3s;
}

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

.main-nav a:hover::after {
  width: 100%;
}

.nav-cta {
  padding: 10px 24px;
  border-radius: 30px;
  color: #fff !important;
  font-weight: 700 !important;
  background: var(--coral);
  box-shadow: 0 4px 18px rgba(255, 90, 95, 0.35);
  transition: all 0.3s !important;
}

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

.nav-cta:hover {
  background: var(--coral-deep);
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(255, 90, 95, 0.45);
}

.menu-toggle {
  display: none;
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--cream-card);
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 1rem;
  color: var(--ink);
}

/* ---------- Hero ---------- */

.hero {
  min-height: 92vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 72px;
  background:
    radial-gradient(circle at 85% 20%, rgba(255, 200, 69, 0.12) 0%, transparent 40%),
    radial-gradient(circle at 10% 80%, rgba(0, 194, 168, 0.08) 0%, transparent 35%),
    var(--cream);
}

.hero::before {
  content: 'ACFUN';
  position: absolute;
  top: 20%;
  right: -30px;
  font-size: 10rem;
  font-weight: 900;
  letter-spacing: -0.04em;
  color: transparent;
  -webkit-text-stroke: 1px rgba(45, 42, 38, 0.04);
  z-index: 0;
  pointer-events: none;
  white-space: nowrap;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: 40px;
  left: -40px;
  width: 120px;
  height: 120px;
  border: 12px solid rgba(255, 90, 95, 0.08);
  border-radius: 50%;
  pointer-events: none;
  z-index: 0;
}

.hero .container {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 60px;
  align-items: center;
  z-index: 1;
}

.hero-content {
  max-width: 720px;
}

.hero-eyebrow {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 2.5px;
  text-transform: uppercase;
  padding: 6px 18px;
  border-radius: 30px;
  margin-bottom: 22px;
  background: rgba(0, 194, 168, 0.1);
  color: var(--teal-deep);
  border: 1.5px solid rgba(0, 194, 168, 0.25);
}

.hero h1 {
  font-size: 3.4rem;
  font-weight: 900;
  line-height: 1.12;
  margin-bottom: 20px;
  letter-spacing: -2px;
  color: var(--ink);
}

.hero h1 .highlight {
  position: relative;
  color: var(--coral);
  display: inline-block;
  z-index: 1;
}

.hero h1 .highlight::after {
  content: '';
  position: absolute;
  bottom: 4px;
  left: -2px;
  width: calc(100% + 4px);
  height: 10px;
  background: var(--gold);
  z-index: -1;
  border-radius: 6px;
  opacity: 0.35;
}

.hero p {
  font-size: 1.1rem;
  opacity: 0.7;
  max-width: 520px;
  margin-bottom: 36px;
  line-height: 1.7;
}

.hero-buttons {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.hero-image {
  border-radius: var(--radius);
  overflow: hidden;
  position: relative;
  box-shadow: var(--shadow-lg);
  transform: rotate(2deg);
  border: 6px solid #fff;
  transition: transform 0.5s ease;
}

.hero-image:hover {
  transform: rotate(0deg) scale(1.02);
}

.hero-image::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(255, 90, 95, 0.08), transparent 40%);
  pointer-events: none;
}

.hero-image img {
  width: 100%;
  height: auto;
  display: block;
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 30px;
  border-radius: 30px;
  font-weight: 700;
  font-size: 0.92rem;
  cursor: pointer;
  border: none;
  text-decoration: none;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  letter-spacing: 0.2px;
}

.btn-primary {
  background: var(--coral);
  color: #fff;
  box-shadow: 0 6px 24px rgba(255, 90, 95, 0.4);
}

.btn-primary:hover {
  background: var(--coral-deep);
  transform: translateY(-3px);
  box-shadow: 0 10px 32px rgba(255, 90, 95, 0.5);
}

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

.btn-outline:hover {
  background: var(--ink);
  color: var(--cream);
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(45, 42, 38, 0.2);
}

/* ---------- Cards Grid ---------- */

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

.category-card {
  border-radius: var(--radius);
  padding: 30px 28px;
  background: var(--cream-card);
  border: 1px solid var(--line);
  transition: all 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
  position: relative;
  overflow: hidden;
}

.category-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--coral);
  border-radius: 0 0 4px 4px;
  opacity: 0;
  transition: opacity 0.3s;
}

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

.category-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}

.category-card:hover::before {
  opacity: 1;
}

.card-icon {
  width: 52px;
  height: 52px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  font-size: 1.4rem;
  background: rgba(255, 90, 95, 0.1);
  transition: all 0.3s;
}

.category-card:nth-child(2) .card-icon { background: rgba(0, 194, 168, 0.1); }
.category-card:nth-child(3) .card-icon { background: rgba(255, 200, 69, 0.15); }
.category-card:nth-child(4) .card-icon { background: rgba(255, 90, 95, 0.1); }

.category-card:hover .card-icon {
  transform: scale(1.1) rotate(-5deg);
}

.card-link {
  font-weight: 700;
  font-size: 0.82rem;
  text-decoration: none;
  color: var(--coral);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-top: 4px;
  transition: gap 0.3s;
}

.card-link:hover {
  gap: 8px;
  color: var(--coral-deep);
}

/* ---------- Features ---------- */

.feature-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.feature-image {
  border-radius: var(--radius);
  overflow: hidden;
  position: relative;
  box-shadow: var(--shadow-lg);
}

.feature-image::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(120deg, rgba(0, 194, 168, 0.06), transparent 50%);
  pointer-events: none;
}

.feature-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease;
}

.feature-block:hover .feature-image img {
  transform: scale(1.03);
}

.feature-text {
  padding: 20px 0;
}

.feature-text .section-title {
  font-size: 2.2rem;
  margin-bottom: 18px;
}

.feature-text .section-desc {
  margin-bottom: 28px;
}

.feature-list {
  list-style: none;
}

.feature-list li {
  padding: 8px 0;
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 500;
  color: var(--ink-soft);
  font-size: 0.95rem;
}

.feature-list li::before {
  content: '✓';
  font-weight: 900;
  color: var(--teal);
  background: rgba(0, 194, 168, 0.1);
  width: 24px;
  height: 24px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  flex-shrink: 0;
}

/* ---------- Stats ---------- */

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

.stat-item {
  padding: 36px 24px;
  border-radius: var(--radius);
  background: var(--cream-card);
  border: 1px solid var(--line);
  transition: all 0.3s;
  position: relative;
  overflow: hidden;
}

.stat-item::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 30px;
  height: 3px;
  border-radius: 3px;
  background: var(--coral);
  transition: width 0.3s;
}

.stat-item:hover::after {
  width: 60px;
}

.stat-item:nth-child(2)::after { background: var(--teal); }
.stat-item:nth-child(3)::after { background: var(--gold); }
.stat-item:nth-child(4)::after { background: var(--coral); }

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

.stat-number {
  font-size: 2.8rem;
  font-weight: 900;
  letter-spacing: -2px;
  background: linear-gradient(135deg, var(--coral), var(--gold));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.2;
}

.stat-item:nth-child(2) .stat-number {
  background: linear-gradient(135deg, var(--teal), var(--teal-deep));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-label {
  font-size: 0.9rem;
  opacity: 0.6;
  margin-top: 8px;
  font-weight: 500;
}

/* ---------- Content Wall ---------- */

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

.content-wall-item {
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--cream-card);
  border: 1px solid var(--line);
  transition: all 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
  position: relative;
}

.content-wall-item:hover {
  transform: translateY(-6px) rotate(-0.5deg);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}

.content-wall-item img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.content-wall-item:hover img {
  transform: scale(1.05);
}

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

.content-wall-body h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 8px;
  line-height: 1.3;
}

.content-wall-body p {
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.5;
}

/* ---------- FAQ ---------- */

.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  background: var(--cream-card);
  border: 1px solid var(--line);
  border-radius: 16px;
  margin-bottom: 12px;
  overflow: hidden;
  cursor: pointer;
  transition: all 0.3s;
}

.faq-item:hover {
  border-color: rgba(255, 90, 95, 0.2);
}

.faq-item .faq-question {
  padding: 18px 24px;
  font-weight: 700;
  font-size: 0.98rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  color: var(--ink);
  position: relative;
}

.faq-item .faq-question::after {
  content: '+';
  font-size: 1.2rem;
  font-weight: 400;
  color: var(--coral);
  transition: transform 0.3s;
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: rgba(255, 90, 95, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
}

.faq-item .faq-answer {
  padding: 0 24px;
  display: none;
  opacity: 0.7;
  font-size: 0.93rem;
  line-height: 1.7;
  padding-bottom: 18px;
}

.faq-item.open {
  border-color: rgba(255, 90, 95, 0.3);
  box-shadow: var(--shadow-sm);
}

.faq-item.open .faq-answer {
  display: block;
  animation: fadeIn 0.3s ease;
}

.faq-item.open .faq-question::after {
  transform: rotate(45deg);
  background: var(--coral);
  color: #fff;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 0.7; transform: translateY(0); }
}

/* ---------- CTA Banner ---------- */

.cta-banner {
  padding: 64px 40px;
  text-align: center;
  border-radius: 20px;
  background:
    radial-gradient(circle at 20% 80%, rgba(255, 200, 69, 0.25) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255, 90, 95, 0.2) 0%, transparent 50%),
    linear-gradient(135deg, var(--coral), var(--coral-deep));
  color: #fff;
  position: relative;
  overflow: hidden;
  box-shadow: 0 20px 60px rgba(255, 90, 95, 0.4);
}

.cta-banner::before {
  content: '✦';
  position: absolute;
  top: 20px;
  right: 40px;
  font-size: 3rem;
  opacity: 0.3;
  animation: spin 12s linear infinite;
}

.cta-banner::after {
  content: '●';
  position: absolute;
  bottom: 20px;
  left: 40px;
  font-size: 2rem;
  opacity: 0.3;
  animation: pulse 3s ease-in-out infinite;
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 0.3; }
  50% { transform: scale(1.2); opacity: 0.5; }
}

.cta-banner h2 {
  font-size: 2rem;
  font-weight: 900;
  letter-spacing: -1px;
  margin-bottom: 14px;
  color: #fff;
}

.cta-banner .btn-primary {
  background: #fff;
  color: var(--coral-deep);
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.15);
  margin-top: 8px;
}

.cta-banner .btn-primary:hover {
  background: var(--cream);
  transform: translateY(-3px);
  box-shadow: 0 10px 32px rgba(0, 0, 0, 0.2);
}

/* ---------- Footer ---------- */

.site-footer {
  padding: 72px 0 28px;
  background: var(--cream-deep);
  border-top: 1px solid rgba(45, 42, 38, 0.05);
  color: var(--ink);
}

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

.footer-brand .logo {
  font-size: 1.4rem;
  margin-bottom: 12px;
}

.footer-brand p {
  font-size: 0.9rem;
  color: var(--ink-soft);
  line-height: 1.7;
  max-width: 300px;
}

.footer-col h4 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 16px;
  position: relative;
  padding-bottom: 8px;
}

.footer-col h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 20px;
  height: 2px;
  background: var(--coral);
  border-radius: 2px;
}

.footer-col ul {
  list-style: none;
}

.footer-col ul li {
  margin-bottom: 8px;
}

.footer-col ul a {
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 0.88rem;
  transition: all 0.2s;
}

.footer-col ul a:hover {
  color: var(--coral);
  padding-left: 4px;
}

.footer-bottom {
  border-top: 1px solid rgba(45, 42, 38, 0.08);
  margin-top: 48px;
  padding-top: 20px;
  text-align: center;
  font-size: 0.82rem;
  color: var(--ink-faint);
}

/* ---------- Utility ---------- */

.text-accent {
  color: var(--coral);
  font-weight: 700;
}

.seo-description {
  max-width: 600px;
  margin: 0 auto 48px;
  opacity: 0.7;
  line-height: 1.7;
  font-size: 1rem;
}

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

/* ---------- Media Queries ---------- */

@media (max-width: 992px) {
  .hero h1 {
    font-size: 2.6rem;
  }
  .hero .container {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .hero-image {
    max-width: 480px;
  }
  .hero {
    padding-top: 100px;
    min-height: auto;
  }
}

@media (max-width: 768px) {
  .feature-block {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
  .main-nav {
    display: none;
  }
  .menu-toggle {
    display: flex;
  }
  .main-nav.open {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 72px;
    left: 0;
    width: 100%;
    background: var(--cream);
    padding: 24px;
    gap: 16px;
    box-shadow: var(--shadow-md);
    border-bottom: 1px solid var(--line);
    z-index: 999;
  }
  .main-nav.open li {
    width: 100%;
  }
  .main-nav.open a {
    display: block;
    padding: 10px 0;
    font-size: 1rem;
    border-bottom: 1px solid var(--line);
  }
  .nav-cta {
    text-align: center;
    margin-top: 8px;
    border-radius: 12px;
  }
  .section-title,
  .feature-text .section-title {
    font-size: 2rem;
  }
  .section {
    padding: 72px 0;
  }
  .cta-banner {
    padding: 48px 28px;
  }
  .cta-banner h2 {
    font-size: 1.6rem;
  }
}

@media (max-width: 480px) {
  .cards-grid,
  .content-wall,
  .stats-bar {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }
  .hero-buttons {
    flex-direction: column;
    align-items: stretch;
  }
  .hero-buttons .btn {
    justify-content: center;
  }
  .hero h1 {
    font-size: 2.1rem;
  }
  .hero p {
    font-size: 1rem;
  }
  .section-title {
    font-size: 1.8rem;
  }
  .stat-number {
    font-size: 2.2rem;
  }
  .section-label {
    font-size: 0.7rem;
    letter-spacing: 2px;
  }
  .hero::before {
    font-size: 4rem;
    top: 30%;
  }
  .hero-image {
    transform: rotate(0deg);
  }
}