/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

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

html { scroll-behavior: smooth; }

body {
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: #2c3e50;
  background: #f5f6f8;
}

h1, h2, h3, h4 {
  font-family: "Noto Serif SC", "Source Han Serif SC", Georgia, serif;
  color: #0B1F3A;
  line-height: 1.35;
}

a { color: #C8102E; text-decoration: none; transition: color 0.2s; }
a:hover { color: #a00d25; }

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

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

section { padding: 72px 0; }

.section-header {
  text-align: center;
  margin-bottom: 48px;
}

.section-header h2 {
  font-size: 2rem;
  margin-bottom: 12px;
}

.section-header p {
  color: #5a6a7a;
  max-width: 640px;
  margin: 0 auto;
  font-size: 1.05rem;
}

.section-label {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #C8102E;
  margin-bottom: 8px;
}

/* ===== Header / Nav ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: #0B1F3A;
  box-shadow: 0 2px 12px rgba(0,0,0,0.25);
}

.nav-bar {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-family: "Noto Serif SC", Georgia, serif;
  font-size: 1.25rem;
  font-weight: 700;
  text-decoration: none;
}

.brand:hover { color: #fff; }

.brand-mark { width: 36px; height: 36px; flex-shrink: 0; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-links a {
  color: rgba(255,255,255,0.85);
  font-size: 0.95rem;
  padding: 8px 14px;
  border-bottom: 2px solid transparent;
  transition: color 0.2s, border-color 0.2s;
  text-decoration: none;
}

.nav-links a:hover { color: #fff; }

.nav-links a.active {
  color: #fff;
  border-bottom-color: #C8102E;
}

.nav-cta {
  background: #C8102E !important;
  color: #fff !important;
  border-radius: 4px;
  border-bottom: none !important;
  margin-left: 8px;
  padding: 8px 18px !important;
}

.nav-cta:hover {
  background: #a00d25 !important;
  color: #fff !important;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 4px;
  border: none;
  cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  font-family: inherit;
  text-decoration: none;
}

.btn-primary {
  background: #C8102E;
  color: #fff;
  box-shadow: 0 2px 8px rgba(200,16,46,0.3);
}

.btn-primary:hover {
  background: #a00d25;
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(200,16,46,0.4);
}

.btn-secondary {
  background: #0B1F3A;
  color: #fff;
}

.btn-secondary:hover { background: #163256; }

.btn-outline {
  background: transparent;
  color: #C8102E;
  border: 2px solid #C8102E;
}

.btn-outline:hover {
  background: #C8102E;
  color: #fff;
}

.btn-ghost {
  background: rgba(255,255,255,0.12);
  color: #fff;
  border: 1px solid rgba(255,255,255,0.4);
}

.btn-ghost:hover { background: rgba(255,255,255,0.2); }

.btn-sm { padding: 8px 16px; font-size: 0.9rem; }

.btn:disabled { opacity: 0.7; cursor: not-allowed; }

/* ===== Hero ===== */
.hero {
  background: linear-gradient(135deg, #0B1F3A 0%, #163256 60%, #1a3d6e 100%);
  padding: 120px 0 80px;
  color: #fff;
  overflow: hidden;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(200,16,46,0.2);
  border: 1px solid rgba(200,16,46,0.4);
  color: #ffb3be;
  font-size: 0.85rem;
  padding: 6px 14px;
  border-radius: 4px;
  margin-bottom: 20px;
}

.hero h1 {
  font-size: 2.5rem;
  color: #fff;
  margin-bottom: 20px;
}

.hero h1 span { color: #ffb3be; }

.hero-sub {
  font-size: 1.1rem;
  color: rgba(255,255,255,0.82);
  margin-bottom: 28px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 28px;
}

.hero-trust {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
}

.hero-trust li {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.9rem;
  color: rgba(255,255,255,0.75);
}

.hero-trust svg { width: 16px; height: 16px; flex-shrink: 0; }

.hero-chart {
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 4px;
  padding: 24px;
  box-shadow: 0 8px 32px rgba(0,0,0,0.3);
}

.hero-chart-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
  font-size: 0.85rem;
  color: rgba(255,255,255,0.7);
}

.hero-chart-title { font-weight: 600; color: #fff; }

.hero-chart-change { color: #4ade80; font-weight: 600; }

/* ===== Stats Bar ===== */
.stats-bar {
  background: #fff;
  padding: 40px 0;
  border-bottom: 1px solid #e8eaed;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  text-align: center;
}

.stat-num {
  font-family: "Noto Serif SC", Georgia, serif;
  font-size: 2.4rem;
  font-weight: 700;
  color: #0B1F3A;
  line-height: 1.1;
}

.stat-num small {
  font-size: 1rem;
  color: #C8102E;
}

.stat-label {
  font-size: 0.9rem;
  color: #5a6a7a;
  margin-top: 6px;
}

/* ===== Cards ===== */
.card {
  background: #fff;
  border: 1px solid #e0e3e8;
  border-radius: 4px;
  box-shadow: 0 2px 8px rgba(11,31,58,0.06);
  padding: 28px;
  transition: box-shadow 0.2s, transform 0.2s;
}

.card:hover {
  box-shadow: 0 6px 20px rgba(11,31,58,0.1);
  transform: translateY(-2px);
}

.card-icon {
  width: 48px;
  height: 48px;
  background: rgba(200,16,46,0.08);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.card-icon svg { width: 24px; height: 24px; color: #C8102E; }

.card h3 {
  font-size: 1.15rem;
  margin-bottom: 10px;
}

.card p {
  color: #5a6a7a;
  font-size: 0.95rem;
  line-height: 1.75;
}

/* ===== Feature Grid ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

/* ===== Deep Dive (Alternating) ===== */
.deep-dive-item {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
  margin-bottom: 64px;
}

.deep-dive-item:last-child { margin-bottom: 0; }

.deep-dive-item.reverse { direction: rtl; }
.deep-dive-item.reverse > * { direction: ltr; }

.deep-dive-visual {
  background: #fff;
  border: 1px solid #e0e3e8;
  border-radius: 4px;
  padding: 32px;
  box-shadow: 0 2px 12px rgba(11,31,58,0.06);
}

.deep-dive-content h3 {
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.deep-dive-content p {
  color: #5a6a7a;
  margin-bottom: 12px;
  line-height: 1.8;
}

.deep-dive-list {
  list-style: none;
  margin-top: 16px;
}

.deep-dive-list li {
  padding: 8px 0 8px 24px;
  position: relative;
  color: #3a4a5a;
  font-size: 0.95rem;
}

.deep-dive-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 14px;
  width: 8px;
  height: 8px;
  background: #C8102E;
  border-radius: 2px;
}

/* ===== Platform Downloads ===== */
.platform-section { background: #fff; }

.platform-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.platform-card {
  text-align: center;
  padding: 32px 20px;
}

.platform-card .card-icon { margin: 0 auto 16px; }

.platform-card h3 { margin-bottom: 8px; }

.platform-card p {
  font-size: 0.88rem;
  color: #5a6a7a;
  margin-bottom: 16px;
}

.platform-card.featured {
  border-color: #C8102E;
  position: relative;
}

.platform-card.featured::before {
  content: "推荐";
  position: absolute;
  top: -1px;
  right: 16px;
  background: #C8102E;
  color: #fff;
  font-size: 0.75rem;
  padding: 3px 10px;
  border-radius: 0 0 4px 4px;
}

/* ===== Comparison Table ===== */
.comparison-wrap {
  overflow-x: auto;
  border-radius: 4px;
  border: 1px solid #e0e3e8;
  box-shadow: 0 2px 8px rgba(11,31,58,0.06);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  font-size: 0.95rem;
}

.comparison-table th,
.comparison-table td {
  padding: 14px 18px;
  text-align: center;
  border-bottom: 1px solid #e8eaed;
}

.comparison-table th {
  background: #0B1F3A;
  color: #fff;
  font-weight: 600;
}

.comparison-table th:first-child { text-align: left; }

.comparison-table td:first-child {
  text-align: left;
  font-weight: 600;
  color: #0B1F3A;
}

.comparison-table tr:last-child td { border-bottom: none; }

.comparison-table tr:nth-child(even) td { background: #f9fafb; }

.check-yes { color: #16a34a; font-weight: 700; }
.check-no { color: #94a3b8; }
.check-partial { color: #d97706; }

/* ===== Reviews ===== */
.reviews-section { background: #fff; }

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card { padding: 24px; }

.review-stars {
  display: flex;
  gap: 2px;
  margin-bottom: 12px;
}

.review-stars svg { width: 18px; height: 18px; color: #f59e0b; }

.review-text {
  color: #3a4a5a;
  font-size: 0.95rem;
  line-height: 1.75;
  margin-bottom: 16px;
  font-style: italic;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 10px;
}

.review-avatar {
  width: 40px;
  height: 40px;
  background: #0B1F3A;
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
}

.review-meta { font-size: 0.85rem; }
.review-meta strong { display: block; color: #0B1F3A; }
.review-meta span { color: #94a3b8; }

/* ===== FAQ Accordion ===== */
.faq-list { max-width: 800px; margin: 0 auto; }

.faq-item {
  background: #fff;
  border: 1px solid #e0e3e8;
  border-radius: 4px;
  margin-bottom: 12px;
  box-shadow: 0 1px 4px rgba(11,31,58,0.04);
}

.faq-item details { padding: 0; }

.faq-item summary {
  padding: 18px 24px;
  cursor: pointer;
  font-weight: 600;
  color: #0B1F3A;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background 0.2s;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::after {
  content: "+";
  font-size: 1.4rem;
  color: #C8102E;
  font-weight: 400;
  transition: transform 0.2s;
}

.faq-item details[open] summary::after {
  content: "\2212";
}

.faq-item summary:hover { background: #f9fafb; }

.faq-answer {
  padding: 0 24px 18px;
  color: #5a6a7a;
  line-height: 1.8;
  font-size: 0.95rem;
}

/* ===== Footer ===== */
.site-footer {
  background: #0B1F3A;
  color: rgba(255,255,255,0.7);
  padding: 48px 0 32px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 32px;
}

.footer-brand {
  color: #fff;
  font-family: "Noto Serif SC", Georgia, serif;
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.footer-desc {
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 16px;
}

.footer-security {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  background: rgba(200,16,46,0.15);
  border: 1px solid rgba(200,16,46,0.3);
  border-radius: 4px;
  padding: 12px 16px;
  font-size: 0.88rem;
  color: rgba(255,255,255,0.85);
}

.footer-security svg { width: 18px; height: 18px; flex-shrink: 0; margin-top: 2px; color: #ffb3be; }

.footer-col h4 {
  color: #fff;
  font-size: 0.95rem;
  margin-bottom: 14px;
}

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

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

.footer-col a {
  color: rgba(255,255,255,0.65);
  font-size: 0.9rem;
  text-decoration: none;
  transition: color 0.2s;
}

.footer-col a:hover { color: #fff; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 24px;
  text-align: center;
  font-size: 0.85rem;
  line-height: 1.7;
}

/* ===== Download Page ===== */
.page-hero {
  background: linear-gradient(135deg, #0B1F3A, #163256);
  padding: 110px 0 60px;
  color: #fff;
  text-align: center;
}

.page-hero h1 {
  color: #fff;
  font-size: 2.2rem;
  margin-bottom: 16px;
}

.page-hero p {
  color: rgba(255,255,255,0.8);
  max-width: 680px;
  margin: 0 auto;
  font-size: 1.05rem;
}

.download-featured {
  background: #fff;
  border: 2px solid #C8102E;
  border-radius: 4px;
  padding: 40px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 32px;
  align-items: center;
  margin-bottom: 40px;
  box-shadow: 0 4px 16px rgba(200,16,46,0.1);
}

.download-featured-info h2 {
  font-size: 1.6rem;
  margin-bottom: 12px;
}

.download-featured-info p {
  color: #5a6a7a;
  margin-bottom: 8px;
}

.download-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 16px;
  font-size: 0.88rem;
  color: #5a6a7a;
}

.download-meta span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.steps-section { background: #fff; }

.steps-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

.steps-block h3 {
  font-size: 1.25rem;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 2px solid #C8102E;
  display: inline-block;
}

.step-list { list-style: none; counter-reset: step; }

.step-list li {
  counter-increment: step;
  padding: 16px 0 16px 52px;
  position: relative;
  border-bottom: 1px solid #f0f1f3;
  color: #3a4a5a;
  line-height: 1.7;
}

.step-list li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 16px;
  width: 32px;
  height: 32px;
  background: #0B1F3A;
  color: #fff;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
}

.requirements-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.req-card h4 {
  font-size: 1.05rem;
  margin-bottom: 12px;
  color: #C8102E;
}

.req-card ul {
  list-style: none;
  font-size: 0.92rem;
  color: #5a6a7a;
}

.req-card li {
  padding: 6px 0 6px 18px;
  position: relative;
}

.req-card li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 13px;
  width: 6px;
  height: 6px;
  background: #0B1F3A;
  border-radius: 50%;
}

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

.changelog-item {
  background: #fff;
  border: 1px solid #e0e3e8;
  border-radius: 4px;
  padding: 20px 24px;
  margin-bottom: 12px;
  box-shadow: 0 1px 4px rgba(11,31,58,0.04);
}

.changelog-item h4 {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 1rem;
  margin-bottom: 8px;
}

.changelog-date {
  font-size: 0.85rem;
  color: #94a3b8;
  font-weight: 400;
  font-family: "Noto Sans SC", sans-serif;
}

.changelog-item ul {
  list-style: none;
  font-size: 0.92rem;
  color: #5a6a7a;
}

.changelog-item li {
  padding: 4px 0 4px 16px;
  position: relative;
}

.changelog-item li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 5px;
  height: 5px;
  background: #C8102E;
  border-radius: 50%;
}

.security-note {
  background: rgba(11,31,58,0.04);
  border: 1px solid #e0e3e8;
  border-left: 4px solid #C8102E;
  border-radius: 4px;
  padding: 24px 28px;
  margin-top: 40px;
}

.security-note h3 {
  font-size: 1.1rem;
  margin-bottom: 10px;
}

.security-note p {
  color: #5a6a7a;
  font-size: 0.95rem;
  line-height: 1.8;
}

/* ===== Article Page (zh-cn) ===== */
.article-hero {
  background: #fff;
  padding: 110px 0 40px;
  border-bottom: 1px solid #e8eaed;
}

.article-hero h1 {
  font-size: 2rem;
  margin-bottom: 16px;
  max-width: 800px;
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.88rem;
  color: #94a3b8;
  margin-bottom: 20px;
}

.article-lead {
  font-size: 1.1rem;
  color: #5a6a7a;
  line-height: 1.85;
  max-width: 800px;
}

.article-body {
  background: #fff;
  padding: 48px 0 72px;
}

.article-content {
  max-width: 800px;
  margin: 0 auto;
}

.article-content h2 {
  font-size: 1.45rem;
  margin: 40px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid #e8eaed;
}

.article-content h3 {
  font-size: 1.15rem;
  margin: 28px 0 12px;
}

.article-content p {
  color: #3a4a5a;
  margin-bottom: 16px;
  line-height: 1.85;
  text-align: justify;
}

.article-content ul, .article-content ol {
  margin: 0 0 16px 24px;
  color: #3a4a5a;
  line-height: 1.85;
}

.article-content li { margin-bottom: 6px; }

.article-cta {
  background: linear-gradient(135deg, #0B1F3A, #163256);
  border-radius: 4px;
  padding: 32px 36px;
  margin: 40px 0;
  text-align: center;
}

.article-cta h3 {
  color: #fff;
  font-size: 1.3rem;
  margin-bottom: 10px;
}

.article-cta p {
  color: rgba(255,255,255,0.8);
  margin-bottom: 20px;
  text-align: center;
}

.article-cta a {
  display: inline-block;
  background: #C8102E;
  color: #fff;
  padding: 12px 32px;
  border-radius: 4px;
  font-weight: 600;
  text-decoration: none;
  transition: background 0.2s;
}

.article-cta a:hover {
  background: #a00d25;
  color: #fff;
}

.article-toc {
  background: #f5f6f8;
  border: 1px solid #e0e3e8;
  border-radius: 4px;
  padding: 24px 28px;
  margin-bottom: 32px;
}

.article-toc h3 {
  font-size: 1rem;
  margin-bottom: 12px;
}

.article-toc ol {
  margin: 0 0 0 20px;
  font-size: 0.92rem;
}

.article-toc a { color: #0B1F3A; }
.article-toc a:hover { color: #C8102E; }

/* ===== Responsive ===== */
@media (max-width: 992px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-chart { order: -1; max-width: 480px; margin: 0 auto; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .deep-dive-item, .deep-dive-item.reverse { grid-template-columns: 1fr; direction: ltr; }
  .platform-grid { grid-template-columns: repeat(2, 1fr); }
  .reviews-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-inner { grid-template-columns: 1fr; }
  .download-featured { grid-template-columns: 1fr; text-align: center; }
  .download-featured .btn { margin: 0 auto; }
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  section { padding: 48px 0; }
  .hero h1 { font-size: 1.8rem; }
  .features-grid { grid-template-columns: 1fr; }
  .platform-grid { grid-template-columns: 1fr; }
  .reviews-grid { grid-template-columns: 1fr; }
  .steps-grid { grid-template-columns: 1fr; }
  .requirements-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
}