/* === DeepSeek zhuti4 — Deep Navy Editorial === */

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

:root {
  --brand: oklch(0.38 0.11 242);
  --brand-hover: oklch(0.32 0.10 242);
  --brand-light: oklch(0.95 0.02 248);
  --brand-surface: oklch(0.97 0.01 250);
  --accent: oklch(0.72 0.14 85);
  --accent-hover: oklch(0.65 0.13 85);
  --bg: oklch(0.985 0.002 250);
  --surface: oklch(1 0 0);
  --ink: oklch(0.15 0.01 250);
  --ink-secondary: oklch(0.38 0.01 250);
  --ink-muted: oklch(0.55 0.01 250);
  --border: oklch(0.87 0.005 250);
  --border-light: oklch(0.93 0.003 250);
  --font: "PingFang SC","Microsoft YaHei","Hiragino Sans GB",system-ui,-apple-system,sans-serif;
  --mono: "SF Mono","Cascadia Code","Consolas",monospace;
  --w: 1040px;
  --radius: 2px;
  --shadow: 0 1px 3px oklch(0 0 0 / 0.06);
}

html { scroll-behavior: smooth; font-size: 17px; }
body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

/* Nav */
.navbar {
  position: sticky; top: 0; z-index: 100;
  background: oklch(1 0 0 / 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.navbar .wrap {
  display: flex; align-items: center; justify-content: space-between;
  height: 56px;
}
.nav-logo {
  display: flex; align-items: center; gap: 8px;
  font-weight: 700; font-size: 1.1rem; color: var(--brand);
  text-decoration: none; letter-spacing: -0.02em;
}
.nav-logo svg { width: 24px; height: 24px; flex-shrink: 0; }
.nav-links { display: flex; gap: 28px; align-items: center; }
.nav-links a {
  font-size: 0.85rem; font-weight: 500; color: var(--ink-secondary);
  text-decoration: none; letter-spacing: 0.01em;
  transition: color 0.15s;
}
.nav-links a:hover, .nav-links a.active { color: var(--brand); }

/* Hero */
.hero {
  padding: 80px 0 64px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}
.hero .wrap { max-width: 720px; text-align: left; }
.hero h1 {
  font-size: 3rem; font-weight: 800; line-height: 1.15;
  color: var(--ink); letter-spacing: -0.03em;
}
.hero h1 span { color: var(--brand); }
.hero p {
  font-size: 1.15rem; color: var(--ink-secondary);
  margin-top: 20px; max-width: 560px; line-height: 1.75;
}
.hero-actions { margin-top: 32px; display: flex; gap: 12px; flex-wrap: wrap; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 10px 24px; border-radius: var(--radius); font-size: 0.9rem;
  font-weight: 600; text-decoration: none; cursor: pointer;
  border: 1.5px solid transparent; transition: all 0.15s;
  letter-spacing: 0.01em;
}
.btn-primary {
  background: var(--brand); color: #fff; border-color: var(--brand);
}
.btn-primary:hover { background: var(--brand-hover); }
.btn-accent {
  background: var(--accent); color: #1a1a1a; border-color: var(--accent);
}
.btn-accent:hover { background: var(--accent-hover); }
.btn-outline {
  background: transparent; color: var(--brand); border-color: var(--brand);
}
.btn-outline:hover { background: var(--brand-light); }
.btn-lg { padding: 14px 32px; font-size: 1rem; }

/* Sections */
.section { padding: 72px 0; }
.section-alt {
  padding: 72px 0;
  background: var(--brand-surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.section-heading {
  font-size: 1.75rem; font-weight: 700; letter-spacing: -0.02em;
  margin-bottom: 8px; color: var(--ink);
}
.section-sub {
  font-size: 1rem; color: var(--ink-muted); margin-bottom: 40px;
  max-width: 560px; line-height: 1.6;
}

/* Stats bar */
.stats-bar {
  display: flex; gap: 32px; margin-top: 48px;
  padding: 28px 0; border-top: 1px solid var(--border);
}
.stat-item { flex: 1; min-width: 0; }
.stat-num {
  font-size: 2.25rem; font-weight: 800; color: var(--brand);
  letter-spacing: -0.03em; line-height: 1.2;
}
.stat-label {
  font-size: 0.8rem; color: var(--ink-muted); font-weight: 500;
  margin-top: 4px; text-transform: uppercase; letter-spacing: 0.06em;
}

/* Editorial feature grid */
.editorial-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px 40px;
}
.editorial-item { border-top: 2px solid var(--border); padding-top: 20px; }
.editorial-item h3 {
  font-size: 1.15rem; font-weight: 700; color: var(--ink);
  margin-bottom: 8px; letter-spacing: -0.01em;
}
.editorial-item p {
  font-size: 0.9rem; color: var(--ink-secondary); line-height: 1.65;
}

/* Capability list */
.cap-list { display: flex; flex-direction: column; gap: 16px; }
.cap-row {
  display: flex; align-items: flex-start; gap: 16px;
  padding: 16px 0; border-bottom: 1px solid var(--border-light);
}
.cap-row:last-child { border-bottom: none; }
.cap-row-icon { font-size: 1.5rem; flex-shrink: 0; width: 36px; text-align: center; }
.cap-row h4 { font-size: 0.95rem; font-weight: 600; color: var(--ink); margin-bottom: 4px; }
.cap-row p { font-size: 0.85rem; color: var(--ink-secondary); line-height: 1.55; }

/* FAQ compact */
.faq-compact { margin-top: 24px; }
.faq-compact details {
  border-bottom: 1px solid var(--border-light); padding: 14px 0;
}
.faq-compact details:first-child { border-top: 1px solid var(--border-light); }
.faq-compact summary {
  font-weight: 600; font-size: 0.95rem; cursor: pointer;
  color: var(--ink); list-style: none; display: flex; justify-content: space-between;
}
.faq-compact summary::after { content: "+"; font-size: 1.1rem; color: var(--brand); }
.faq-compact details[open] summary::after { content: "−"; }
.faq-compact p {
  font-size: 0.85rem; color: var(--ink-secondary); margin-top: 8px;
  padding-left: 0; line-height: 1.6;
}

/* CTA section */
.cta-section { text-align: center; padding: 64px 0; }
.cta-section h2 { font-size: 1.75rem; font-weight: 700; }

/* Footer */
.footer {
  padding: 28px 0; border-top: 1px solid var(--border);
  font-size: 0.8rem; color: var(--ink-muted);
}
.footer .wrap { display: flex; justify-content: space-between; align-items: center; }
.footer nav a {
  color: var(--ink-muted); text-decoration: none; margin-left: 16px;
}
.footer nav a:hover { color: var(--brand); }

/* Download page */
.download-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px; margin-top: 32px;
}
.download-card {
  padding: 28px; border: 1px solid var(--border); background: var(--surface);
  transition: border-color 0.15s;
}
.download-card:hover { border-color: var(--brand); }
.download-card h3 { font-size: 1.05rem; font-weight: 700; margin-bottom: 6px; }
.download-card .ver { font-size: 0.8rem; color: var(--ink-muted); margin-bottom: 12px; }
.download-card .desc { font-size: 0.82rem; color: var(--ink-secondary); margin-bottom: 16px; }

/* Feature table */
.feat-table { width: 100%; border-collapse: collapse; margin-top: 32px; font-size: 0.9rem; }
.feat-table th, .feat-table td {
  border-bottom: 1px solid var(--border); padding: 12px 16px; text-align: left;
}
.feat-table th { font-weight: 600; color: var(--ink); background: var(--brand-surface); }
.feat-table td { color: var(--ink-secondary); }

/* Pricing table */
.pricing-table { width: 100%; border-collapse: collapse; margin-top: 24px; font-size: 0.88rem; }
.pricing-table th, .pricing-table td {
  border: 1px solid var(--border); padding: 14px 18px; text-align: left;
}
.pricing-table th {
  background: var(--brand); color: #fff; font-weight: 600; border-color: var(--brand);
}
.pricing-table tr:nth-child(even) td { background: var(--brand-surface); }
.price-highlight { font-weight: 700; color: var(--brand); font-size: 1.1rem; }

/* FAQ page */
.faq-category { margin-bottom: 40px; }
.faq-category h3 {
  font-size: 1.15rem; font-weight: 700; color: var(--brand);
  margin-bottom: 12px; padding-bottom: 8px;
  border-bottom: 2px solid var(--brand);
  display: inline-block;
}
.faq-page details {
  border-bottom: 1px solid var(--border-light); padding: 16px 0;
}
.faq-page summary {
  font-weight: 600; font-size: 0.95rem; cursor: pointer; color: var(--ink);
  list-style: none;
}
.faq-page summary::before { content: "Q. "; color: var(--brand); font-weight: 700; }
.faq-page p {
  font-size: 0.88rem; color: var(--ink-secondary); margin-top: 8px;
  padding-left: 28px; line-height: 1.65;
}

/* 404 */
.error-page { text-align: center; padding: 120px 0; }
.error-page h1 { font-size: 5rem; font-weight: 800; color: var(--brand); }
.error-page p { font-size: 1.1rem; color: var(--ink-secondary); margin: 16px 0 28px; }

@media (max-width: 768px) {
  .hero h1 { font-size: 2rem; }
  .editorial-grid { grid-template-columns: 1fr; gap: 32px; }
  .stats-bar { flex-wrap: wrap; gap: 20px; }
  .stat-num { font-size: 1.6rem; }
  .nav-links { gap: 16px; }
  .download-grid { grid-template-columns: 1fr; }
}