/* ========== CSS Variables ========== */
:root {
  --primary: #4285f4;
  --primary-dark: #1a73e8;
  --accent-red: #ea4335;
  --accent-yellow: #fbbc04;
  --accent-green: #34a853;
  --bg-dark: #0f1419;
  --bg-card: rgba(255,255,255,0.03);
  --bg-glass: rgba(255,255,255,0.06);
  --text-primary: #e7e9ea;
  --text-secondary: #8b98a5;
  --border-color: rgba(255,255,255,0.08);
  --gradient-mesh: radial-gradient(ellipse 80% 50% at 50% -20%, rgba(66,133,244,0.3), transparent),
                   radial-gradient(ellipse 60% 40% at 100% 0%, rgba(234,67,53,0.15), transparent),
                   radial-gradient(ellipse 50% 50% at 0% 100%, rgba(52,168,83,0.12), transparent);
  --shadow-glow: 0 0 60px rgba(66,133,244,0.15);
  --radius: 16px;
  --radius-sm: 10px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========== Reset & Base ========== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg-dark);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }

/* ========== Layout ========== */
.wrap { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ========== Animations ========== */
@keyframes spin { from { transform: rotate(0deg); } to { transform: rotate(360deg); } }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-12px); } }
@keyframes pulse-glow { 0%, 100% { box-shadow: 0 0 20px rgba(66,133,244,0.4); } 50% { box-shadow: 0 0 40px rgba(66,133,244,0.6); } }
@keyframes gradient-shift { 0% { background-position: 0% 50%; } 50% { background-position: 100% 50%; } 100% { background-position: 0% 50%; } }
@keyframes fade-up { from { opacity: 0; transform: translateY(30px); } to { opacity: 1; transform: translateY(0); } }

/* ========== Navigation ========== */
.topnav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(15,20,25,0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
}
.topnav .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}
.brand svg { width: 32px; height: 32px; }
.navlist {
  display: flex;
  gap: 8px;
}
.navlist a {
  padding: 8px 18px;
  border-radius: 100px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
}
.navlist a:hover { color: var(--text-primary); background: var(--bg-glass); }
.navlist a.on {
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  box-shadow: 0 4px 15px rgba(66,133,244,0.3);
}

/* ========== Hero Section ========== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 100px 0 60px;
  background: var(--gradient-mesh), var(--bg-dark);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(66,133,244,0.08) 0%, transparent 70%);
  transform: translate(-50%, -50%);
  pointer-events: none;
}
.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.hero-text h1 {
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 24px;
  background: linear-gradient(135deg, #fff 0%, #a8c7fa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-text p {
  font-size: 1.15rem;
  color: var(--text-secondary);
  margin-bottom: 36px;
  max-width: 480px;
}
.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
}
.hero-logo-wrap {
  position: relative;
  width: 280px;
  height: 280px;
  animation: float 6s ease-in-out infinite;
}
.hero-logo-wrap svg {
  width: 100%;
  height: 100%;
  filter: drop-shadow(0 20px 60px rgba(66,133,244,0.4));
}
.hero-ring {
  position: absolute;
  inset: -30px;
  border: 2px solid rgba(66,133,244,0.2);
  border-radius: 50%;
  animation: pulse-glow 3s ease-in-out infinite;
}
.hero-ring:nth-child(2) { inset: -60px; animation-delay: 0.5s; border-color: rgba(234,67,53,0.15); }
.hero-ring:nth-child(3) { inset: -90px; animation-delay: 1s; border-color: rgba(52,168,83,0.1); }

/* ========== Buttons ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 28px;
  border-radius: 100px;
  font-size: 1rem;
  font-weight: 600;
  transition: var(--transition);
}
.btn svg { width: 20px; height: 20px; }
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  box-shadow: 0 4px 20px rgba(66,133,244,0.4);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(66,133,244,0.5);
}
.btn-outline {
  border: 2px solid var(--border-color);
  color: var(--text-primary);
  background: var(--bg-glass);
}
.btn-outline:hover {
  border-color: var(--primary);
  background: rgba(66,133,244,0.1);
}
.btn-ghost {
  color: var(--text-secondary);
  padding: 10px 20px;
}
.btn-ghost:hover { color: var(--primary); }

/* ========== Section Titles ========== */
.section-header {
  text-align: center;
  margin-bottom: 60px;
}
.section-header h2 {
  font-size: clamp(1.75rem, 3vw, 2.25rem);
  font-weight: 700;
  margin-bottom: 12px;
}
.section-header p {
  color: var(--text-secondary);
  font-size: 1.05rem;
}

/* ========== Features Grid (Bento Style) ========== */
.features-section {
  padding: 100px 0;
  background: linear-gradient(180deg, transparent, rgba(66,133,244,0.03));
}
.bento-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: auto auto;
  gap: 20px;
}
.bento-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 32px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.bento-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent-green));
  opacity: 0;
  transition: var(--transition);
}
.bento-card:hover {
  border-color: rgba(66,133,244,0.3);
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}
.bento-card:hover::before { opacity: 1; }
.bento-card.large { grid-column: span 2; }
.bento-card.tall { grid-row: span 2; display: flex; flex-direction: column; }
.bento-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(66,133,244,0.15), rgba(66,133,244,0.05));
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}
.bento-icon svg { width: 28px; height: 28px; stroke: var(--primary); }
.bento-card h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 12px;
}
.bento-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ========== Platform Cards ========== */
.platforms-section {
  padding: 100px 0;
}
.platforms-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.platform-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-align: center;
  transition: var(--transition);
  position: relative;
}
.platform-card.featured {
  border-color: var(--primary);
  background: linear-gradient(180deg, rgba(66,133,244,0.08), transparent);
}
.platform-card.featured::before {
  content: '推荐';
  position: absolute;
  top: -1px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 16px;
  border-radius: 0 0 8px 8px;
}
.platform-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}
.platform-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.platform-icon svg { width: 48px; height: 48px; fill: var(--text-primary); }
.platform-card h4 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 8px;
}
.platform-card .version {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 20px;
}
.platform-card .btn { width: 100%; }

/* ========== Reviews Carousel ========== */
.reviews-section {
  padding: 100px 0;
  background: var(--gradient-mesh), var(--bg-dark);
}
.reviews-track {
  display: flex;
  gap: 24px;
  overflow-x: auto;
  padding: 20px 0;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
}
.reviews-track::-webkit-scrollbar { display: none; }
.review-card {
  flex: 0 0 360px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 28px;
  scroll-snap-align: start;
}
.review-stars {
  display: flex;
  gap: 4px;
  margin-bottom: 16px;
}
.review-stars svg { width: 18px; height: 18px; fill: var(--accent-yellow); }
.review-card blockquote {
  font-size: 1rem;
  line-height: 1.7;
  margin-bottom: 20px;
  color: var(--text-primary);
}
.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
}
.review-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent-green));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 1rem;
}
.review-meta strong { display: block; font-size: 0.95rem; }
.review-meta span { font-size: 0.85rem; color: var(--text-secondary); }

/* ========== FAQ Accordion ========== */
.faq-section {
  padding: 100px 0;
}
.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}
.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: var(--transition);
}
.faq-item:hover { border-color: rgba(66,133,244,0.3); }
.faq-q {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-primary);
  text-align: left;
  transition: var(--transition);
}
.faq-q:hover { background: var(--bg-glass); }
.faq-chevron {
  width: 20px;
  height: 20px;
  stroke: var(--text-secondary);
  transition: var(--transition);
  flex-shrink: 0;
}
.faq-item.open .faq-chevron { transform: rotate(180deg); stroke: var(--primary); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
}
.faq-item.open .faq-a {
  max-height: 300px;
  padding: 0 24px 20px;
}
.faq-a p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ========== Stats Bar ========== */
.stats-bar {
  padding: 60px 0;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
  text-align: center;
}
.stat-item h3 {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary), var(--accent-green));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 8px;
}
.stat-item p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* ========== Footer ========== */
.site-footer {
  padding: 60px 0 40px;
  background: rgba(0,0,0,0.3);
  border-top: 1px solid var(--border-color);
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 16px;
}
.footer-brand svg { width: 28px; height: 28px; }
.footer-desc {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.7;
  max-width: 320px;
}
.footer-col h5 {
  font-size: 0.9rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 16px;
  color: var(--text-secondary);
}
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  transition: var(--transition);
}
.footer-col ul a:hover { color: var(--primary); }
.footer-bottom {
  padding-top: 30px;
  border-top: 1px solid var(--border-color);
  text-align: center;
}
.security-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(52,168,83,0.1);
  border: 1px solid rgba(52,168,83,0.2);
  border-radius: 100px;
  padding: 10px 20px;
  margin-bottom: 16px;
  font-size: 0.9rem;
  color: var(--accent-green);
}
.security-badge svg { width: 18px; height: 18px; stroke: var(--accent-green); }
.copyright {
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* ========== Download Page Specific ========== */
.download-hero {
  padding: 140px 0 80px;
  background: var(--gradient-mesh), var(--bg-dark);
  text-align: center;
}
.download-hero h1 {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  margin-bottom: 16px;
}
.download-hero p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto 40px;
}
.main-download-card {
  max-width: 600px;
  margin: 0 auto 80px;
  background: var(--bg-card);
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  padding: 48px;
  position: relative;
  overflow: hidden;
}
.main-download-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(180deg, rgba(66,133,244,0.1), transparent);
  pointer-events: none;
}
.main-download-card h2 {
  font-size: 1.5rem;
  margin-bottom: 12px;
}
.main-download-card .version-info {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 24px;
}
.main-download-card .btn { font-size: 1.1rem; padding: 16px 36px; }
.download-features {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-top: 24px;
  flex-wrap: wrap;
}
.download-features span {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}
.download-features svg { width: 18px; height: 18px; stroke: var(--accent-green); }

/* ========== Other Platforms Section ========== */
.other-platforms {
  padding: 80px 0;
}
.other-platforms h2 {
  text-align: center;
  font-size: 1.75rem;
  margin-bottom: 48px;
}

/* ========== System Requirements ========== */
.requirements-section {
  padding: 80px 0;
  background: rgba(0,0,0,0.2);
}
.requirements-tabs {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 40px;
}
.tab-btn {
  padding: 10px 24px;
  border-radius: 100px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  transition: var(--transition);
}
.tab-btn:hover { border-color: var(--primary); color: var(--text-primary); }
.tab-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}
.tab-content { display: none; }
.tab-content.active { display: block; animation: fade-up 0.4s ease; }
.requirements-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  max-width: 800px;
  margin: 0 auto;
}
.req-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 20px 24px;
  display: flex;
  align-items: flex-start;
  gap: 16px;
}
.req-item svg { width: 24px; height: 24px; stroke: var(--primary); flex-shrink: 0; margin-top: 2px; }
.req-item strong { display: block; margin-bottom: 4px; }
.req-item span { color: var(--text-secondary); font-size: 0.9rem; }

/* ========== SEO Page (zh-cn) ========== */
.article-hero {
  padding: 140px 0 60px;
  background: var(--gradient-mesh), var(--bg-dark);
}
.article-hero h1 {
  font-size: clamp(2rem, 4vw, 2.5rem);
  font-weight: 700;
  margin-bottom: 20px;
  max-width: 800px;
}
.article-meta {
  display: flex;
  align-items: center;
  gap: 20px;
  color: var(--text-secondary);
  font-size: 0.9rem;
}
.article-meta span {
  display: flex;
  align-items: center;
  gap: 6px;
}
.article-meta svg { width: 16px; height: 16px; }
.article-content {
  padding: 60px 0;
}
.article-body {
  max-width: 800px;
  margin: 0 auto;
}
.article-body h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin: 48px 0 20px;
  padding-left: 16px;
  border-left: 4px solid var(--primary);
}
.article-body h3 {
  font-size: 1.2rem;
  font-weight: 600;
  margin: 32px 0 16px;
}
.article-body p {
  color: var(--text-secondary);
  font-size: 1rem;
  line-height: 1.8;
  margin-bottom: 20px;
}
.article-body ul {
  margin: 20px 0;
  padding-left: 24px;
}
.article-body li {
  color: var(--text-secondary);
  margin-bottom: 12px;
  position: relative;
}
.article-body li::before {
  content: '';
  position: absolute;
  left: -20px;
  top: 10px;
  width: 6px;
  height: 6px;
  background: var(--primary);
  border-radius: 50%;
}
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: 32px 0;
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
}
.comparison-table th,
.comparison-table td {
  padding: 16px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}
.comparison-table th {
  background: var(--bg-glass);
  font-weight: 600;
  font-size: 0.9rem;
}
.comparison-table td { font-size: 0.95rem; color: var(--text-secondary); }
.comparison-table tr:last-child td { border-bottom: none; }
.cta-banner {
  background: linear-gradient(135deg, rgba(66,133,244,0.15), rgba(52,168,83,0.1));
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 48px;
  text-align: center;
  margin: 60px 0;
}
.cta-banner h3 {
  font-size: 1.5rem;
  margin-bottom: 16px;
}
.cta-banner p {
  color: var(--text-secondary);
  margin-bottom: 24px;
}
.version-timeline {
  margin: 32px 0;
  padding-left: 24px;
  border-left: 2px solid var(--border-color);
}
.version-item {
  position: relative;
  padding: 0 0 32px 24px;
}
.version-item::before {
  content: '';
  position: absolute;
  left: -7px;
  top: 6px;
  width: 12px;
  height: 12px;
  background: var(--primary);
  border-radius: 50%;
  border: 2px solid var(--bg-dark);
}
.version-item h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
}
.version-item p {
  font-size: 0.9rem;
  margin-bottom: 0;
}

/* ========== Responsive ========== */
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; text-align: center; }
  .hero-text p { margin: 0 auto 36px; }
  .hero-visual { order: -1; margin-bottom: 40px; }
  .hero-logo-wrap { width: 200px; height: 200px; }
  .bento-grid { grid-template-columns: 1fr 1fr; }
  .bento-card.large { grid-column: span 1; }
  .bento-card.tall { grid-row: span 1; }
  .platforms-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .wrap { padding: 0 16px; }
  .navlist { display: none; }
  .bento-grid { grid-template-columns: 1fr; }
  .platforms-grid { grid-template-columns: 1fr; }
  .faq-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .stats-grid { grid-template-columns: 1fr 1fr; gap: 24px; }
  .requirements-grid { grid-template-columns: 1fr; }
  .review-card { flex: 0 0 300px; }
}
@media (max-width: 480px) {
  .hero { padding: 80px 0 40px; }
  .hero-logo-wrap { width: 160px; height: 160px; }
  .btn { padding: 12px 24px; font-size: 0.95rem; }
  .main-download-card { padding: 32px 24px; }
}