:root {
  --bg: #f4f6fb;
  --surface: #ffffff;
  --ink: #1f2937;
  --muted: #5b6475;
  --line: #e5e9f2;
  --brand: #cb1f27;
  --brand-dark: #a41820;
  --brand-soft: #ffe9eb;
  --teal: #0f766e;
  --blue: #1d4ed8;
  --orange: #d97706;
  --gold: #b45309;
  --radius: 16px;
  --shadow: 0 12px 32px rgba(19, 28, 48, 0.08);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: radial-gradient(circle at 10% 0%, #fff4f5 0%, #f4f6fb 40%), var(--bg);
  line-height: 1.7;
}

.container {
  width: min(1160px, 92%);
  margin: 0 auto;
}

.top-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(8px);
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--line);
}

.nav-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  color: #111827;
  white-space: nowrap;
}

.brand-mark {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  background: #fff;
  border: 1px solid #f0d8da;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  box-shadow: inset 0 0 0 1px #fff, 0 3px 10px rgba(217, 43, 43, 0.12);
}

.nav-menu {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
}

.nav-link {
  color: #374151;
  text-decoration: none;
  font-size: 14px;
  padding: 7px 12px;
  border-radius: 999px;
  transition: background-color .2s ease, color .2s ease;
}

.nav-link:hover,
.nav-link.active {
  color: var(--brand-dark);
  background: var(--brand-soft);
}

section { padding: 76px 0; }

.section-head {
  margin-bottom: 26px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--line);
  color: #4b5563;
  font-size: 13px;
  margin-bottom: 14px;
}

.eyebrow-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--brand);
}

h1, h2, h3, p { margin: 0; }

h1 { font-size: clamp(30px, 4.2vw, 48px); line-height: 1.2; letter-spacing: .2px; }
h2 { font-size: clamp(24px, 3.2vw, 34px); line-height: 1.25; margin-bottom: 12px; }
h3 { font-size: 20px; line-height: 1.35; margin-bottom: 10px; }

.sub {
  color: var(--muted);
  max-width: 780px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  gap: 26px;
  align-items: stretch;
}

.hero-copy,
.hero-panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: calc(var(--radius) + 4px);
  box-shadow: var(--shadow);
  padding: 28px;
}

.hero-copy p { color: #4b5563; margin-top: 14px; }

.positioning {
  margin-top: 16px;
  padding-left: 14px;
  border-left: 3px solid #f5c2c5;
  color: #334155;
  font-weight: 600;
}

.hero-actions {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.btn {
  border: 0;
  border-radius: 11px;
  padding: 12px 18px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: transform .15s ease, box-shadow .2s ease, background-color .2s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.btn:disabled { cursor: not-allowed; opacity: .8; }

.btn-primary {
  background: linear-gradient(135deg, #d92b2b, #b71f25);
  color: #fff;
  box-shadow: 0 8px 18px rgba(183, 31, 37, 0.3);
}

.btn-primary:hover { transform: translateY(-1px); }

.btn-soft {
  background: #fff;
  color: #9f1239;
  border: 1px solid #f4b5bb;
}

.btn-soft:hover { background: #fff6f7; }

.stats-grid {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.stat-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px;
}

.stat-num { font-size: 28px; line-height: 1; font-weight: 700; color: var(--brand-dark); }
.stat-label { color: #667085; font-size: 13px; margin-top: 7px; }

.panel-list {
  margin-top: 16px;
  display: grid;
  gap: 12px;
}

.panel-item {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 12px;
  align-items: start;
  background: #fff;
}

.panel-item p { margin-top: 4px; color: #5d6778; font-size: 14px; }

.icon-wrap {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: #fff5f6;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid #ffd6da;
  flex-shrink: 0;
}

.feature-grid {
  margin-top: 20px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.feature-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: 0 4px 18px rgba(27, 39, 67, .04);
}

.feature-card p { color: #4f5a6f; }

.deep-grid {
  margin-top: 28px;
  display: grid;
  gap: 14px;
}

.deep-item {
  display: grid;
  grid-template-columns: 1.2fr .8fr;
  gap: 16px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.deep-item p + p { margin-top: 10px; color: #4f5a6f; }

.deep-visual {
  border-radius: 12px;
  border: 1px solid #e7ecf6;
  background: linear-gradient(160deg, #f9fbff, #fff7f8);
  padding: 12px;
  display: grid;
  gap: 10px;
}

.bar {
  height: 10px;
  border-radius: 999px;
  background: #ecf0f7;
  overflow: hidden;
}

.bar > span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, #d92b2b, #f59e0b);
  border-radius: inherit;
}

.platform-grid,
.review-grid,
.shield-grid,
.version-grid {
  display: grid;
  gap: 16px;
}

.platform-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.review-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.shield-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); margin: 20px 0 24px; }
.version-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: 0 4px 20px rgba(25, 39, 68, .05);
}

.tag {
  display: inline-block;
  font-size: 12px;
  padding: 4px 8px;
  border-radius: 999px;
  background: #eef2ff;
  color: #334155;
  margin: 8px 0 10px;
}

.platform-meta,
.platform-req,
.review-user,
.shield-text,
.price,
.faq-answer,
.table-note { color: #5c6678; font-size: 14px; }

.platform-btn { width: 100%; margin-top: 12px; }

.stars {
  display: flex;
  gap: 4px;
  margin-bottom: 10px;
}

.review-user { margin-top: 10px; font-weight: 600; color: #344155; }

.security-block {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
}

.security-copy p { color: #4f5a6f; margin-top: 8px; }

table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 18px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
}

th, td {
  padding: 12px;
  text-align: left;
  border-bottom: 1px solid #edf1f7;
  font-size: 14px;
}

th { background: #f8fafc; color: #1f2937; }
tr:last-child td { border-bottom: 0; }

.highlight { color: #9f1239; font-weight: 700; }

.version-card.featured {
  border-color: #f6c4c8;
  box-shadow: 0 10px 26px rgba(217, 43, 43, .12);
}

.version-card ul {
  list-style: none;
  padding: 0;
  margin: 12px 0 0;
  display: grid;
  gap: 8px;
}

.version-card li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 8px;
  align-items: start;
  color: #4f5a6f;
  font-size: 14px;
}

.faq-list {
  display: grid;
  gap: 12px;
  margin-top: 18px;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
  overflow: hidden;
}

.faq-question {
  width: 100%;
  border: 0;
  background: #fff;
  text-align: left;
  padding: 15px 16px;
  font-size: 16px;
  font-weight: 600;
  color: #1f2937;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
}

.faq-question svg {
  flex-shrink: 0;
  transition: transform .2s ease;
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height .25s ease;
  padding: 0 16px;
}

.faq-answer p {
  margin: 0 0 14px;
  color: #4f5a6f;
}

.faq-item.open .faq-answer { max-height: 280px; }
.faq-item.open .faq-question svg { transform: rotate(180deg); }

footer {
  padding: 30px 0 42px;
  color: #4b5563;
  text-align: center;
  border-top: 1px solid var(--line);
  margin-top: 26px;
  background: #fff;
}

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

@media (max-width: 1060px) {
  .hero-grid,
  .deep-item { grid-template-columns: 1fr; }
  .platform-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .shield-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .review-grid,
  .version-grid,
  .feature-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 760px) {
  .nav-inner { padding: 10px 0; align-items: flex-start; flex-direction: column; }
  .nav-menu { justify-content: flex-start; }
  .stats-grid,
  .platform-grid,
  .review-grid,
  .shield-grid,
  .version-grid,
  .feature-grid { grid-template-columns: 1fr; }
  section { padding: 62px 0; }
  .hero-copy,
  .hero-panel,
  .card,
  .feature-card,
  .deep-item,
  .security-block { padding: 16px; }
}