:root {
  --primary: #FF6A00;
  --primary-dark: #E55F00;
  --primary-light: #FFF5EB;
  --secondary: #0078D4;
  --text: #1A1A1A;
  --text-secondary: #555555;
  --text-muted: #888888;
  --bg: #FFFFFF;
  --bg-light: #F8F9FA;
  --bg-warm: #FFF8F0;
  --border: #E5E7EB;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
  --radius: 12px;
  --radius-lg: 20px;
  --max-width: 1200px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  line-height: 1.6;
  background: var(--bg);
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== NAVIGATION ========== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.navbar-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.navbar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 20px;
  color: var(--text);
  text-decoration: none;
}
.navbar-brand svg { flex-shrink: 0; }
.navbar-links {
  display: flex;
  gap: 8px;
  list-style: none;
}
.navbar-links a {
  display: block;
  padding: 8px 18px;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}
.navbar-links a:hover {
  color: var(--primary);
  background: var(--primary-light);
}
.navbar-links a.active {
  color: var(--primary);
  background: var(--primary-light);
  font-weight: 600;
}

/* ========== BUTTONS ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 10px;
  font-size: 16px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}
.btn:disabled { opacity: 0.7; cursor: not-allowed; }
.btn-primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 4px 16px rgba(255,106,0,0.35);
}
.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(255,106,0,0.45);
}
.btn-secondary {
  background: var(--bg-light);
  color: var(--text);
  border: 1px solid var(--border);
}
.btn-secondary:hover {
  background: var(--border);
  transform: translateY(-2px);
}
.btn-large {
  padding: 16px 40px;
  font-size: 18px;
  border-radius: 12px;
}

/* ========== SECTIONS ========== */
.section {
  padding: 80px 0;
}
.section-alt {
  background: var(--bg-light);
}
.section-warm {
  background: var(--bg-warm);
}
.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 56px;
}
.section-header h2 {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 16px;
  line-height: 1.25;
}
.section-header p {
  font-size: 18px;
  color: var(--text-secondary);
}

/* ========== HERO ========== */
.hero {
  padding: 80px 0 100px;
  background: linear-gradient(135deg, var(--bg-warm) 0%, #fff 50%, #f0f7ff 100%);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -100px;
  right: -100px;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(255,106,0,0.08) 0%, transparent 70%);
  border-radius: 50%;
}
.hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.hero-content h1 {
  font-size: 52px;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}
.hero-content .hero-subtitle {
  font-size: 20px;
  color: var(--text-secondary);
  margin-bottom: 32px;
  line-height: 1.6;
}
.hero-badges {
  display: flex;
  gap: 16px;
  margin-top: 28px;
  flex-wrap: wrap;
}
.hero-badge {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  color: var(--text-muted);
}
.hero-visual {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.hero-visual img {
  width: 100%;
  border-radius: var(--radius-lg);
}

/* ========== FEATURE CARDS ========== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}
.feature-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  transition: all 0.3s;
}
.feature-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
  border-color: transparent;
}
.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}
.feature-icon svg { width: 28px; height: 28px; }
.feature-card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 12px;
}
.feature-card p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ========== PLATFORM DOWNLOADS ========== */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}
.platform-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-align: center;
  transition: all 0.3s;
}
.platform-card:hover {
  box-shadow: var(--shadow);
  border-color: var(--primary);
  transform: translateY(-2px);
}
.platform-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 16px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.platform-icon svg { width: 48px; height: 48px; }
.platform-card h4 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
}
.platform-card p {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 16px;
}
.platform-card .btn {
  width: 100%;
  padding: 12px;
  font-size: 15px;
}

/* ========== DETAIL SECTIONS ========== */
.detail-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin-bottom: 80px;
}
.detail-block.reverse { direction: rtl; }
.detail-block.reverse > * { direction: ltr; }
.detail-block:last-child { margin-bottom: 0; }
.detail-img {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.detail-img img {
  width: 100%;
  border-radius: var(--radius-lg);
}
.detail-text h3 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 16px;
}
.detail-text p {
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}
.detail-text ul {
  list-style: none;
  margin-top: 16px;
}
.detail-text ul li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-bottom: 10px;
  font-size: 15px;
  color: var(--text-secondary);
}
.detail-text ul li svg {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  margin-top: 2px;
}

/* ========== REVIEWS ========== */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}
.review-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}
.review-stars {
  display: flex;
  gap: 4px;
  margin-bottom: 12px;
}
.review-stars svg {
  width: 18px;
  height: 18px;
  color: #FFB800;
}
.review-text {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 16px;
}
.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
}
.review-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), #ff9a44);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 600;
  font-size: 16px;
}
.review-author-info strong {
  font-size: 14px;
  display: block;
}
.review-author-info span {
  font-size: 13px;
  color: var(--text-muted);
}

/* ========== STATS ========== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 32px;
}
.stat-item {
  text-align: center;
  padding: 24px;
}
.stat-number {
  font-size: 48px;
  font-weight: 800;
  color: var(--primary);
  line-height: 1;
  margin-bottom: 8px;
}
.stat-label {
  font-size: 15px;
  color: var(--text-secondary);
}

/* ========== COMPARISON TABLE ========== */
.compare-table-wrap {
  overflow-x: auto;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}
.compare-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
}
.compare-table th,
.compare-table td {
  padding: 16px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.compare-table th {
  background: var(--bg-light);
  font-weight: 600;
  font-size: 14px;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.compare-table tr:last-child td { border-bottom: none; }
.compare-table td:first-child { font-weight: 500; }
.compare-table .check {
  color: #22C55E;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 500;
}
.compare-table .cross {
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.compare-table .highlight {
  background: var(--primary-light);
}

/* ========== FAQ ========== */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}
.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 24px 0;
}
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  cursor: pointer;
  font-size: 18px;
  font-weight: 600;
  user-select: none;
}
.faq-question svg {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  color: var(--text-muted);
  transition: transform 0.3s;
}
.faq-item.active .faq-question svg { transform: rotate(180deg); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s, padding 0.4s;
}
.faq-item.active .faq-answer {
  max-height: 400px;
  padding-top: 16px;
}
.faq-answer p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ========== DOWNLOAD PAGE ========== */
.download-hero {
  background: linear-gradient(135deg, var(--bg-warm) 0%, #fff 100%);
  padding: 60px 0 80px;
}
.download-main {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 60px;
  align-items: center;
}
.download-info h1 {
  font-size: 42px;
  font-weight: 800;
  margin-bottom: 16px;
}
.download-info p {
  font-size: 17px;
  color: var(--text-secondary);
  margin-bottom: 32px;
}
.download-meta {
  display: flex;
  gap: 24px;
  margin-bottom: 32px;
  flex-wrap: wrap;
}
.download-meta-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--text-muted);
}
.download-meta-item svg { width: 18px; height: 18px; }
.download-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}
.download-img {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.download-img img { width: 100%; }

/* ========== INSTALL STEPS ========== */
.steps-list {
  max-width: 800px;
  margin: 0 auto;
}
.step-item {
  display: flex;
  gap: 24px;
  margin-bottom: 32px;
  align-items: flex-start;
}
.step-number {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-weight: 700;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.step-content h4 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 6px;
}
.step-content p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ========== REQUIREMENTS ========== */
.req-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}
.req-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}
.req-card h4 {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 16px;
}
.req-card h4 svg { width: 24px; height: 24px; }
.req-card ul {
  list-style: none;
}
.req-card ul li {
  font-size: 14px;
  color: var(--text-secondary);
  padding: 6px 0;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
}
.req-card ul li:last-child { border-bottom: none; }

/* ========== CHANGELOG ========== */
.changelog-list {
  max-width: 800px;
  margin: 0 auto;
}
.changelog-item {
  display: flex;
  gap: 24px;
  padding: 24px 0;
  border-bottom: 1px solid var(--border);
}
.changelog-version {
  flex-shrink: 0;
  width: 120px;
}
.changelog-version .version-tag {
  display: inline-block;
  padding: 4px 12px;
  background: var(--primary);
  color: #fff;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 6px;
}
.changelog-version .version-date {
  font-size: 13px;
  color: var(--text-muted);
}
.changelog-content h4 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
}
.changelog-content ul {
  list-style: none;
}
.changelog-content ul li {
  font-size: 14px;
  color: var(--text-secondary);
  padding: 4px 0;
  display: flex;
  align-items: flex-start;
  gap: 8px;
}
.changelog-content ul li::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--primary);
  margin-top: 8px;
  flex-shrink: 0;
}

/* ========== SECURITY ========== */
.security-block {
  display: flex;
  align-items: center;
  gap: 16px;
  background: var(--bg-light);
  border-radius: var(--radius);
  padding: 28px 32px;
  max-width: 800px;
  margin: 0 auto;
}
.security-block svg {
  width: 48px;
  height: 48px;
  flex-shrink: 0;
  color: #22C55E;
}
.security-block h4 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 4px;
}
.security-block p {
  font-size: 14px;
  color: var(--text-secondary);
}

/* ========== FOOTER ========== */
.footer {
  background: #111827;
  color: #9CA3AF;
  padding: 40px 0;
  text-align: center;
  font-size: 14px;
  line-height: 1.8;
}
.footer p { margin-bottom: 6px; }
.footer strong { color: #fff; }

/* ========== SEO PAGE ========== */
.article-section {
  max-width: 800px;
  margin: 0 auto;
  padding: 60px 24px;
}
.article-section h2 {
  font-size: 28px;
  font-weight: 700;
  margin: 40px 0 16px;
}
.article-section h3 {
  font-size: 22px;
  font-weight: 600;
  margin: 32px 0 12px;
}
.article-section p {
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}
.article-section ul {
  margin: 16px 0;
  padding-left: 24px;
  color: var(--text-secondary);
}
.article-section ul li { margin-bottom: 8px; }
.article-cta {
  background: linear-gradient(135deg, var(--primary-light), #fff);
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  padding: 40px;
  text-align: center;
  margin: 48px 0;
}
.article-cta h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 12px;
  margin-top: 0;
}
.article-cta p {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

/* ========== UTILITIES ========== */
.text-center { text-align: center; }
.mt-4 { margin-top: 16px; }
.mt-8 { margin-top: 32px; }
.mb-4 { margin-bottom: 16px; }
.tag {
  display: inline-block;
  padding: 4px 12px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
}

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

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

.animate-in {
  animation: fadeUp 0.6s ease-out forwards;
}

/* ========== RESPONSIVE ========== */
@media (max-width: 960px) {
  .hero-inner,
  .download-main,
  .detail-block {
    grid-template-columns: 1fr;
  }
  .detail-block.reverse { direction: ltr; }
  .hero-content h1 { font-size: 36px; }
  .section-header h2 { font-size: 28px; }
  .detail-text h3 { font-size: 24px; }
}

@media (max-width: 640px) {
  .navbar-links a { padding: 6px 12px; font-size: 14px; }
  .hero-content h1 { font-size: 28px; }
  .hero { padding: 48px 0 64px; }
  .section { padding: 48px 0; }
  .btn-large { padding: 14px 28px; font-size: 16px; }
  .stat-number { font-size: 36px; }
}