/* WPS Office Landing Site — Root #1 Design Identity */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --navy: #0B1F3A;
  --navy-light: #132d4f;
  --cyan: #00A3E0;
  --cyan-dark: #0088bb;
  --white: #ffffff;
  --gray-50: #f7f9fc;
  --gray-100: #eef2f7;
  --gray-200: #dde4ed;
  --gray-600: #5a6b7d;
  --gray-800: #2c3e50;
  --max-width: 1100px;
  --nav-height: 64px;
  --shadow: 0 4px 24px rgba(11, 31, 58, 0.12);
  --radius: 8px;
}

html { scroll-behavior: smooth; }

body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: var(--gray-800);
  background: var(--white);
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--cyan); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--cyan-dark); }

/* Keyframes — required for download spinner */
@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ===== Header & Nav ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--navy);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.25);
}

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

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--white);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

.nav-brand svg { flex-shrink: 0; }

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

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

.nav-links a:hover {
  background: rgba(0, 163, 224, 0.2);
  color: var(--white);
}

.nav-links a.active {
  background: var(--cyan);
  color: var(--white);
}

/* ===== Hero ===== */
.hero {
  position: relative;
  background: linear-gradient(135deg, var(--navy) 0%, #0d3a5c 45%, var(--cyan) 100%);
  color: var(--white);
  padding: 80px 24px 100px;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 20% 80%, rgba(0, 163, 224, 0.25) 0%, transparent 60%),
    radial-gradient(ellipse 60% 50% at 85% 20%, rgba(255, 255, 255, 0.08) 0%, transparent 50%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  max-width: var(--max-width);
  margin: 0 auto;
  text-align: center;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(0, 163, 224, 0.3);
  border: 1px solid rgba(0, 163, 224, 0.5);
  border-radius: 20px;
  font-size: 0.85rem;
  margin-bottom: 20px;
  letter-spacing: 0.05em;
}

.hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.4rem);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.hero-brand {
  display: block;
  font-size: clamp(2.8rem, 6vw, 4.2rem);
  background: linear-gradient(90deg, #fff 0%, #b8e8ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 12px;
}

.hero-sub {
  font-size: 1.15rem;
  opacity: 0.92;
  max-width: 680px;
  margin: 0 auto 32px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: center;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  font-size: 1rem;
  font-weight: 600;
  font-family: inherit;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
}

.btn:disabled { cursor: not-allowed; opacity: 0.85; }

.btn-primary {
  background: var(--cyan);
  color: var(--white);
  box-shadow: 0 4px 16px rgba(0, 163, 224, 0.4);
}

.btn-primary:hover:not(:disabled) {
  background: var(--cyan-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 163, 224, 0.5);
}

.btn-outline {
  background: transparent;
  color: var(--white);
  border: 2px solid rgba(255, 255, 255, 0.6);
}

.btn-outline:hover:not(:disabled) {
  background: rgba(255, 255, 255, 0.12);
  border-color: var(--white);
}

.btn-secondary {
  background: var(--navy);
  color: var(--white);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--navy-light);
  transform: translateY(-1px);
}

.btn-lg { padding: 16px 36px; font-size: 1.05rem; }

/* ===== Sections ===== */
section { padding: 72px 24px; }

section:nth-child(even) { background: var(--gray-50); }

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

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

.section-header h2 {
  font-size: clamp(1.75rem, 3.5vw, 2.4rem);
  font-weight: 800;
  color: var(--navy);
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}

.section-header p {
  font-size: 1.05rem;
  color: var(--gray-600);
  max-width: 640px;
  margin: 0 auto;
}

.section-header .accent-line {
  width: 56px;
  height: 4px;
  background: var(--cyan);
  margin: 16px auto 0;
  border-radius: 2px;
}

/* ===== Feature Grid ===== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
}

.feature-card {
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: 12px;
  padding: 32px 28px;
  transition: box-shadow 0.25s, border-color 0.25s;
}

section:nth-child(even) .feature-card { background: var(--white); }

.feature-card:hover {
  box-shadow: var(--shadow);
  border-color: var(--cyan);
}

.feature-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--navy), var(--cyan));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  color: var(--white);
}

.feature-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--gray-600);
  font-size: 0.95rem;
  line-height: 1.75;
}

/* ===== Platform Download Cards ===== */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.platform-card {
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: 12px;
  padding: 28px 24px;
  text-align: center;
  transition: box-shadow 0.25s, transform 0.2s;
}

.platform-card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-3px);
}

.platform-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  color: var(--navy);
}

.platform-card h3 {
  font-size: 1.15rem;
  color: var(--navy);
  margin-bottom: 8px;
}

.platform-card p {
  font-size: 0.9rem;
  color: var(--gray-600);
  margin-bottom: 18px;
}

.platform-card .btn { width: 100%; }

/* ===== Deep Feature / Prose Blocks ===== */
.prose-block {
  max-width: 860px;
  margin: 0 auto;
}

.prose-block h3 {
  font-size: 1.35rem;
  color: var(--navy);
  margin: 32px 0 12px;
  font-weight: 700;
}

.prose-block h3:first-child { margin-top: 0; }

.prose-block p {
  margin-bottom: 16px;
  color: var(--gray-800);
  line-height: 1.85;
}

.prose-columns {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 36px;
  margin-top: 24px;
}

/* ===== Stats ===== */
.stats-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
  margin-bottom: 40px;
}

.stat-item {
  text-align: center;
  padding: 28px 20px;
  background: var(--white);
  border-radius: 12px;
  border: 1px solid var(--gray-200);
}

.stat-number {
  font-size: 2.4rem;
  font-weight: 800;
  color: var(--cyan);
  line-height: 1.1;
}

.stat-label {
  font-size: 0.95rem;
  color: var(--gray-600);
  margin-top: 6px;
}

.trust-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
}

.trust-list li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px 20px;
  background: var(--white);
  border-radius: var(--radius);
  border-left: 4px solid var(--cyan);
}

.trust-list svg { flex-shrink: 0; color: var(--cyan); margin-top: 2px; }

/* ===== Reviews ===== */
.review-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.review-card {
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: 12px;
  padding: 28px;
}

.review-stars {
  color: #f5a623;
  margin-bottom: 12px;
  letter-spacing: 2px;
}

.review-card blockquote {
  font-style: normal;
  color: var(--gray-800);
  line-height: 1.75;
  margin-bottom: 16px;
}

.review-author {
  font-size: 0.9rem;
  color: var(--gray-600);
}

.review-author strong { color: var(--navy); }

/* ===== Comparison Table ===== */
.compare-table-wrap {
  overflow-x: auto;
  border-radius: 12px;
  border: 1px solid var(--gray-200);
  background: var(--white);
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

.compare-table th,
.compare-table td {
  padding: 16px 20px;
  text-align: left;
  border-bottom: 1px solid var(--gray-200);
}

.compare-table th {
  background: var(--navy);
  color: var(--white);
  font-weight: 600;
}

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

.compare-table tr:nth-child(even) td { background: var(--gray-50); }

.compare-table .highlight { color: var(--cyan); font-weight: 700; }

/* ===== FAQ ===== */
.faq-list { max-width: 860px; margin: 0 auto; }

.faq-item {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  margin-bottom: 12px;
  background: var(--white);
  overflow: hidden;
}

.faq-item summary {
  padding: 18px 24px;
  font-weight: 600;
  color: var(--navy);
  cursor: pointer;
  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:hover { background: var(--gray-50); }

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

.faq-item[open] summary::after { transform: rotate(45deg); }

.faq-answer {
  padding: 0 24px 20px;
  color: var(--gray-600);
  line-height: 1.8;
}

/* ===== Download Page Specific ===== */
.download-hero {
  background: linear-gradient(160deg, var(--navy) 0%, #0a2d4a 50%, var(--cyan-dark) 100%);
  padding: 60px 24px 80px;
  color: var(--white);
  text-align: center;
}

.download-hero h1 {
  font-size: clamp(1.9rem, 4vw, 2.8rem);
  font-weight: 800;
  margin-bottom: 16px;
}

.download-main {
  background: var(--white);
  border-radius: 16px;
  box-shadow: var(--shadow);
  padding: 40px;
  margin-top: -48px;
  position: relative;
  z-index: 2;
  text-align: center;
  border: 1px solid var(--gray-200);
}

.download-main .btn-primary { font-size: 1.1rem; padding: 18px 48px; }

.steps-list {
  counter-reset: step;
  list-style: none;
  max-width: 700px;
  margin: 0 auto;
}

.steps-list li {
  counter-increment: step;
  position: relative;
  padding: 20px 20px 20px 64px;
  margin-bottom: 16px;
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
}

.steps-list li::before {
  content: counter(step);
  position: absolute;
  left: 20px;
  top: 50%;
  transform: translateY(-50%);
  width: 32px;
  height: 32px;
  background: var(--cyan);
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
}

.req-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.req-card {
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: 12px;
  padding: 28px;
}

.req-card h3 {
  color: var(--navy);
  margin-bottom: 12px;
  font-size: 1.15rem;
}

.req-card ul {
  list-style: none;
  padding: 0;
}

.req-card li {
  padding: 6px 0;
  padding-left: 20px;
  position: relative;
  color: var(--gray-600);
  font-size: 0.95rem;
}

.req-card li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--cyan);
  font-weight: 700;
}

/* ===== Article Page (zh-cn) ===== */
.article-hero {
  background: linear-gradient(135deg, var(--navy) 0%, #103050 60%, rgba(0, 163, 224, 0.6) 100%);
  padding: 56px 24px 64px;
  color: var(--white);
}

.article-hero h1 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  max-width: var(--max-width);
  margin: 0 auto 16px;
  line-height: 1.25;
}

.article-meta {
  max-width: var(--max-width);
  margin: 0 auto;
  font-size: 0.9rem;
  opacity: 0.85;
}

.article-body {
  max-width: 780px;
  margin: 0 auto;
  padding: 48px 24px 72px;
}

.article-body h2 {
  font-size: 1.6rem;
  color: var(--navy);
  margin: 40px 0 16px;
  font-weight: 800;
  padding-bottom: 8px;
  border-bottom: 3px solid var(--cyan);
}

.article-body h3 {
  font-size: 1.25rem;
  color: var(--navy-light);
  margin: 28px 0 12px;
  font-weight: 700;
}

.article-body p {
  margin-bottom: 18px;
  line-height: 1.9;
  color: var(--gray-800);
}

.article-body ul, .article-body ol {
  margin: 0 0 18px 24px;
  line-height: 1.85;
  color: var(--gray-800);
}

.article-body li { margin-bottom: 8px; }

.article-cta {
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-light) 100%);
  border-radius: 12px;
  padding: 36px 32px;
  text-align: center;
  margin: 40px 0;
  color: var(--white);
}

.article-cta h3 {
  color: var(--white);
  margin: 0 0 12px;
  border: none;
  padding: 0;
}

.article-cta p { color: rgba(255,255,255,0.9); margin-bottom: 20px; }

.article-cta .btn-primary { margin: 0 8px 8px; }

/* ===== Footer ===== */
.site-footer {
  background: var(--navy);
  color: rgba(255, 255, 255, 0.75);
  padding: 40px 24px;
  font-size: 0.88rem;
  line-height: 1.7;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  text-align: center;
}

.footer-security {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(0, 163, 224, 0.15);
  border: 1px solid rgba(0, 163, 224, 0.3);
  padding: 10px 20px;
  border-radius: var(--radius);
  margin-bottom: 20px;
  color: rgba(255, 255, 255, 0.9);
}

.footer-copy {
  opacity: 0.7;
  max-width: 720px;
  margin: 0 auto;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .nav-inner { flex-direction: column; height: auto; padding: 12px 16px; gap: 10px; }
  .nav-links { flex-wrap: wrap; justify-content: center; }
  section { padding: 52px 16px; }
  .hero { padding: 56px 16px 72px; }
  .download-main { padding: 28px 20px; margin-top: -32px; }
  .compare-table { font-size: 0.85rem; }
  .compare-table th, .compare-table td { padding: 12px 14px; }
}