@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@400;500;600;700&display=swap');

:root {
  --teal: #0B6E99;
  --teal-dark: #085578;
  --teal-light: #1285B5;
  --accent: #0A8F6C;
  --accent-hover: #087A5C;
  --bg: #EEF4F8;
  --bg-alt: #E2ECF3;
  --bg-white: #FFFFFF;
  --text: #1A2B3C;
  --text-muted: #4A6070;
  --text-light: #6B8294;
  --border: #C5D5E0;
  --shadow: 0 4px 20px rgba(11, 110, 153, 0.08);
  --radius: 6px;
  --nav-h: 64px;
  --font: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--teal); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent); }
ul, ol { padding-left: 1.25em; }
li { margin-bottom: 0.4em; }
h1, h2, h3, h4 { font-weight: 700; line-height: 1.35; color: var(--text); }
h1 { font-size: 2.4rem; }
h2 { font-size: 1.75rem; margin-bottom: 0.75em; }
h3 { font-size: 1.25rem; margin-bottom: 0.5em; }
p { margin-bottom: 1em; color: var(--text-muted); }
p:last-child { margin-bottom: 0; }

.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== NAV ========== */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--teal);
  height: var(--nav-h);
  box-shadow: 0 2px 12px rgba(8, 85, 120, 0.25);
}

.site-nav .nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-h);
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

.site-nav .logo {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

.site-nav .logo svg {
  flex-shrink: 0;
}

.site-nav .logo:hover {
  color: #fff;
  opacity: 0.92;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 4px;
  padding: 0;
  margin: 0;
}

.nav-links a {
  display: block;
  color: rgba(255, 255, 255, 0.85);
  padding: 8px 18px;
  border-radius: 4px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: background 0.2s, color 0.2s;
}

.nav-links a:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.12);
}

.nav-links a.active,
.nav-links a.current {
  color: #fff;
  background: rgba(255, 255, 255, 0.2);
  font-weight: 600;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: #fff;
  margin: 5px 0;
  border-radius: 1px;
}

/* ========== HERO ========== */
.hero {
  position: relative;
  min-height: calc(100vh - var(--nav-h));
  display: flex;
  align-items: center;
  overflow: hidden;
  background:
    radial-gradient(ellipse 80% 60% at 20% 40%, rgba(10, 143, 108, 0.18) 0%, transparent 55%),
    radial-gradient(ellipse 70% 50% at 80% 20%, rgba(11, 110, 153, 0.35) 0%, transparent 50%),
    radial-gradient(ellipse 60% 70% at 60% 90%, rgba(18, 133, 181, 0.25) 0%, transparent 45%),
    linear-gradient(160deg, #064A6B 0%, #0B6E99 35%, #0A7A8A 65%, #086B5A 100%);
  color: #fff;
}

.hero-bg-svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 1120px;
  margin: 0 auto;
  padding: 80px 24px 90px;
  width: 100%;
}

.hero-brand {
  font-size: 3.2rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  margin-bottom: 0.35em;
  color: #fff;
  line-height: 1.2;
}

.hero h1 {
  font-size: 1.85rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.95);
  margin-bottom: 0.75em;
  max-width: 640px;
}

.hero-desc {
  font-size: 1.1rem;
  color: rgba(255, 255, 255, 0.82);
  max-width: 560px;
  margin-bottom: 2em;
  line-height: 1.8;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  align-items: center;
}

/* ========== BUTTONS ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  line-height: 1.4;
  text-decoration: none;
}

.btn:disabled {
  opacity: 0.75;
  cursor: wait;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 16px rgba(10, 143, 108, 0.35);
}

.btn-primary:hover:not(:disabled) {
  background: var(--accent-hover);
  transform: translateY(-1px);
  color: #fff;
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.5);
  backdrop-filter: blur(4px);
}

.btn-secondary:hover:not(:disabled) {
  background: rgba(255, 255, 255, 0.25);
  color: #fff;
}

.btn-outline {
  background: transparent;
  color: var(--teal);
  border: 1.5px solid var(--teal);
}

.btn-outline:hover:not(:disabled) {
  background: var(--teal);
  color: #fff;
}

.btn-teal {
  background: var(--teal);
  color: #fff;
}

.btn-teal:hover:not(:disabled) {
  background: var(--teal-dark);
  color: #fff;
}

.btn-lg {
  padding: 16px 40px;
  font-size: 1.05rem;
}

.btn-block {
  width: 100%;
}

/* ========== SECTIONS ========== */
.section {
  padding: 72px 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-white {
  background: var(--bg-white);
}

.section-teal {
  background: linear-gradient(135deg, var(--teal-dark) 0%, var(--teal) 50%, #0A7A8A 100%);
  color: #fff;
}

.section-teal h2,
.section-teal h3 {
  color: #fff;
}

.section-teal p {
  color: rgba(255, 255, 255, 0.85);
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 48px;
}

.section-header h2 {
  margin-bottom: 0.5em;
}

.section-header p {
  font-size: 1.05rem;
}

.section-label {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 0.5em;
}

/* ========== CAPABILITY GRID ========== */
.cap-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px 36px;
}

.cap-item {
  text-align: left;
}

.cap-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 16px;
  color: var(--teal);
}

.cap-item h3 {
  margin-bottom: 0.6em;
  font-size: 1.15rem;
}

.cap-item p {
  font-size: 0.95rem;
  line-height: 1.75;
}

/* ========== PLATFORM ========== */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 28px;
}

.platform-item {
  text-align: center;
  padding: 32px 20px;
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.platform-item svg {
  width: 40px;
  height: 40px;
  margin: 0 auto 16px;
  color: var(--teal);
}

.platform-item h3 {
  font-size: 1.1rem;
  margin-bottom: 0.5em;
}

.platform-item p {
  font-size: 0.9rem;
  margin-bottom: 1.25em;
  min-height: 3em;
}

/* ========== FEATURE DEEP ========== */
.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
  margin-bottom: 56px;
}

.feature-row:last-child {
  margin-bottom: 0;
}

.feature-row.reverse {
  direction: rtl;
}

.feature-row.reverse > * {
  direction: ltr;
}

.feature-visual {
  background: linear-gradient(145deg, #0B6E99 0%, #0A8F6C 100%);
  border-radius: 8px;
  min-height: 260px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px;
}

.feature-visual svg {
  width: 120px;
  height: 120px;
  color: rgba(255, 255, 255, 0.9);
}

.feature-text h3 {
  font-size: 1.35rem;
  margin-bottom: 0.75em;
  color: var(--teal-dark);
}

.feature-text p {
  margin-bottom: 1em;
}

.feature-list {
  list-style: none;
  padding: 0;
  margin-top: 1em;
}

.feature-list li {
  position: relative;
  padding-left: 28px;
  margin-bottom: 0.65em;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.feature-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
}

/* ========== STATS ========== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-item .stat-num {
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--teal);
  line-height: 1.2;
  margin-bottom: 0.3em;
}

.stat-item .stat-label {
  font-size: 0.95rem;
  color: var(--text-muted);
  font-weight: 500;
}

.stats-desc {
  margin-top: 48px;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

/* ========== COMPARE ========== */
.compare-table-wrap {
  overflow-x: auto;
  margin-top: 32px;
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-white);
  font-size: 0.95rem;
}

.compare-table th,
.compare-table td {
  padding: 14px 18px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.compare-table th {
  background: var(--teal);
  color: #fff;
  font-weight: 600;
}

.compare-table tr:nth-child(even) td {
  background: rgba(238, 244, 248, 0.6);
}

.compare-table td:first-child {
  font-weight: 600;
  color: var(--text);
  white-space: nowrap;
}

.compare-table .check {
  color: var(--accent);
  font-weight: 700;
}

.compare-table .cross {
  color: var(--text-light);
}

/* ========== TESTIMONIALS ========== */
.review-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.review-item {
  padding: 28px 0;
  border-top: 3px solid var(--teal);
}

.review-item blockquote {
  font-size: 0.98rem;
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 1.25em;
  font-style: normal;
}

.review-author {
  font-weight: 600;
  color: var(--text);
  font-size: 0.95rem;
}

.review-role {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-top: 2px;
}

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

.faq-item {
  padding: 28px 0;
  border-bottom: 1px solid var(--border);
}

.faq-item:first-child {
  padding-top: 0;
}

.faq-item h3 {
  font-size: 1.1rem;
  color: var(--text);
  margin-bottom: 0.65em;
}

.faq-item p {
  font-size: 0.95rem;
  line-height: 1.8;
}

/* ========== CTA BANNER ========== */
.cta-banner {
  text-align: center;
  padding: 64px 24px;
}

.cta-banner h2 {
  margin-bottom: 0.5em;
}

.cta-banner p {
  max-width: 560px;
  margin: 0 auto 1.75em;
  font-size: 1.05rem;
}

/* ========== DOWNLOAD PAGE ========== */
.page-hero {
  background: linear-gradient(135deg, #064A6B 0%, var(--teal) 50%, #0A7A8A 100%);
  color: #fff;
  padding: 64px 0 56px;
  position: relative;
  overflow: hidden;
}

.page-hero .hero-bg-svg {
  opacity: 0.4;
}

.page-hero h1 {
  color: #fff;
  font-size: 2.1rem;
  margin-bottom: 0.5em;
  position: relative;
  z-index: 1;
}

.page-hero p {
  color: rgba(255, 255, 255, 0.85);
  max-width: 640px;
  font-size: 1.05rem;
  position: relative;
  z-index: 1;
}

.download-main {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 48px;
  align-items: start;
}

.download-info h2 {
  color: var(--teal-dark);
  margin-bottom: 0.75em;
}

.download-actions {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 24px;
}

.download-meta {
  margin-top: 20px;
  font-size: 0.9rem;
  color: var(--text-light);
}

.download-meta span {
  display: inline-block;
  margin-right: 16px;
}

.steps-list {
  counter-reset: step;
  list-style: none;
  padding: 0;
  max-width: 720px;
  margin: 0 auto;
}

.steps-list li {
  counter-increment: step;
  position: relative;
  padding: 0 0 36px 64px;
  margin-bottom: 0;
}

.steps-list li:last-child {
  padding-bottom: 0;
}

.steps-list li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 40px;
  height: 40px;
  background: var(--teal);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
}

.steps-list li::after {
  content: "";
  position: absolute;
  left: 19px;
  top: 44px;
  bottom: 0;
  width: 2px;
  background: var(--border);
}

.steps-list li:last-child::after {
  display: none;
}

.steps-list h3 {
  font-size: 1.15rem;
  margin-bottom: 0.4em;
}

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

.req-block h3 {
  color: var(--teal-dark);
  margin-bottom: 0.75em;
  display: flex;
  align-items: center;
  gap: 10px;
}

.req-block ul {
  color: var(--text-muted);
}

.version-timeline {
  max-width: 720px;
  margin: 0 auto;
}

.version-item {
  padding: 24px 0;
  border-bottom: 1px solid var(--border);
}

.version-item:last-child {
  border-bottom: none;
}

.version-tag {
  display: inline-block;
  background: var(--teal);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 3px 12px;
  border-radius: 3px;
  margin-bottom: 8px;
}

.version-item h3 {
  font-size: 1.1rem;
  margin-bottom: 0.4em;
}

/* ========== ARTICLE (zh-cn) ========== */
.article-hero {
  background: linear-gradient(160deg, #064A6B 0%, var(--teal) 40%, #0A8F6C 100%);
  color: #fff;
  padding: 72px 0 60px;
  position: relative;
  overflow: hidden;
}

.article-hero h1 {
  color: #fff;
  font-size: 2.2rem;
  max-width: 720px;
  position: relative;
  z-index: 1;
  margin-bottom: 0.6em;
}

.article-hero .lead {
  color: rgba(255, 255, 255, 0.88);
  font-size: 1.1rem;
  max-width: 640px;
  position: relative;
  z-index: 1;
}

.article-body {
  max-width: 760px;
  margin: 0 auto;
  padding: 56px 24px 40px;
}

.article-body h2 {
  margin-top: 2.2em;
  margin-bottom: 0.7em;
  color: var(--teal-dark);
  padding-bottom: 0.4em;
  border-bottom: 2px solid var(--border);
}

.article-body h2:first-child {
  margin-top: 0;
}

.article-body h3 {
  margin-top: 1.6em;
  margin-bottom: 0.55em;
  color: var(--text);
}

.article-body p {
  font-size: 1.02rem;
  line-height: 1.9;
  margin-bottom: 1.15em;
}

.article-cta {
  background: var(--bg-alt);
  border-left: 4px solid var(--accent);
  padding: 28px 32px;
  margin: 40px 0;
  border-radius: 0 var(--radius) var(--radius) 0;
}

.article-cta h3 {
  margin-top: 0;
  color: var(--teal-dark);
}

.article-cta .btn {
  margin-top: 16px;
}

/* ========== FOOTER ========== */
.site-footer {
  background: #0D2A3A;
  color: rgba(255, 255, 255, 0.75);
  padding: 48px 0 32px;
  font-size: 0.9rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 36px;
}

.footer-brand {
  color: #fff;
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: 12px;
}

.site-footer p {
  color: rgba(255, 255, 255, 0.65);
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 0.75em;
}

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

.footer-links {
  list-style: none;
  padding: 0;
}

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

.footer-links a {
  color: rgba(255, 255, 255, 0.65);
}

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

.footer-security {
  background: rgba(10, 143, 108, 0.15);
  border: 1px solid rgba(10, 143, 108, 0.35);
  border-radius: var(--radius);
  padding: 14px 18px;
  margin-bottom: 28px;
  color: rgba(255, 255, 255, 0.85);
  font-size: 0.9rem;
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.footer-security svg {
  flex-shrink: 0;
  margin-top: 2px;
  color: var(--accent);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 24px;
  text-align: center;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
  line-height: 1.7;
}

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

/* ========== RESPONSIVE ========== */
@media (max-width: 960px) {
  .cap-grid { grid-template-columns: repeat(2, 1fr); }
  .platform-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
  .review-grid { grid-template-columns: 1fr; }
  .feature-row,
  .feature-row.reverse {
    grid-template-columns: 1fr;
    direction: ltr;
  }
  .download-main { grid-template-columns: 1fr; }
  .req-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .hero-brand { font-size: 2.4rem; }
  .hero h1 { font-size: 1.45rem; }
}

@media (max-width: 640px) {
  h1 { font-size: 1.7rem; }
  h2 { font-size: 1.4rem; }
  .section { padding: 52px 0; }
  .cap-grid { grid-template-columns: 1fr; gap: 32px; }
  .platform-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .hero-brand { font-size: 2rem; }
  .hero-content { padding: 56px 20px 64px; }
  .hero-cta { flex-direction: column; align-items: stretch; }
  .btn { width: 100%; }
  .page-hero { padding: 48px 0 40px; }
  .page-hero h1 { font-size: 1.6rem; }
  .article-hero h1 { font-size: 1.65rem; }
  .nav-toggle { display: block; }
  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: var(--teal-dark);
    flex-direction: column;
    padding: 12px;
    gap: 0;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 12px 16px; }
  .compare-table th,
  .compare-table td { padding: 10px 12px; font-size: 0.85rem; }
}

@media (min-width: 641px) {
  .nav-links { display: flex !important; }
}